National Library of Energy BETA

Sample records for numerical study developing

  1. An Integrated Experimental and Numerical Study: Developing a...

    Open Energy Info (EERE)

    in a numerical simulator (modified version of TOUGH2) that can adjust porosity and permeability fields according to experimentally observed chemical fluid-rock interactions...

  2. NREL Developing a Numerical Simulation Tool to Study Hydrokinetic Energy Conversion Devices and Arrays (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-02-01

    New code will help accelerate design improvements by providing a high-fidelity simulation tool to study power performance, structural loading, and the interactions between devices in arrays.

  3. Development of Numerical Simulation Capabilities for In Situ...

    Office of Scientific and Technical Information (OSTI)

    for In Situ Heating of Oil Shale Citation Details In-Document Search Title: Development of Numerical Simulation Capabilities for In Situ Heating of Oil Shale Authors: Hoda, ...

  4. Numerical Studies of Impurities in Fusion Plasmas

    DOE R&D Accomplishments [OSTI]

    Hulse, R. A.

    1982-09-01

    The coupled partial differential equations used to describe the behavior of impurity ions in magnetically confined controlled fusion plasmas require numerical solution for cases of practical interest. Computer codes developed for impurity modeling at the Princeton Plasma Physics Laboratory are used as examples of the types of codes employed for this purpose. These codes solve for the impurity ionization state densities and associated radiation rates using atomic physics appropriate for these low-density, high-temperature plasmas. The simpler codes solve local equations in zero spatial dimensions while more complex cases require codes which explicitly include transport of the impurity ions simultaneously with the atomic processes of ionization and recombination. Typical applications are discussed and computational results are presented for selected cases of interest.

  5. Numerical Modeling Studies of The Dissolution-Diffusion-Convection...

    Office of Scientific and Technical Information (OSTI)

    CO2 Storage in Saline Aquifers Citation Details In-Document Search Title: Numerical Modeling Studies of The Dissolution-Diffusion-Convection ProcessDuring CO2 Storage in ...

  6. Experimental and numerical study of the effective thermal conductivity of

    Office of Scientific and Technical Information (OSTI)

    silica nanocomposites with thermal boundary resistance (Journal Article) | SciTech Connect Experimental and numerical study of the effective thermal conductivity of silica nanocomposites with thermal boundary resistance Citation Details In-Document Search Title: Experimental and numerical study of the effective thermal conductivity of silica nanocomposites with thermal boundary resistance The thermal interface resistance at the macro scale is mainly described by the physical gap between two

  7. Development of Numerical Simulation Capabilities for In Situ...

    Office of Scientific and Technical Information (OSTI)

    Numerical Simulation Capabilities for In Situ Heating of Oil Shale Hoda, Nazish ExxonMobil Upstream Research Company, Houston, TX, USA; Fang, Chen ExxonMobil Upstream Research...

  8. Dispersion of helically corrugated waveguides: Analytical, numerical, and experimental study

    SciTech Connect (OSTI)

    Burt, G.; Ronald, K.; Young, A.R.; Phelps, A.D.R.; Cross, A.W.; Konoplev, I.V.; He, W.; Thomson, J.; Whyte, C.G.; Samsonov, S.V.; Denisov, G.G.; Bratman, V.L.

    2004-10-01

    Helically corrugated waveguides have recently been studied for use in various applications such as interaction regions in gyrotron traveling-wave tubes and gyrotron backward-wave oscillators and as a dispersive medium for passive microwave pulse compression. The paper presents a summary of various methods that can be used for analysis of the wave dispersion of such waveguides. The results obtained from an analytical approach, simulations with the three-dimensional numerical code MAGIC, and cold microwave measurements are analyzed and compared.

  9. Numerical study of thermoacoustic convection in a cavity

    SciTech Connect (OSTI)

    Fusegi, Toru; Farouk, B.; Oran, E.S.

    1995-12-31

    Thermoacoustic convection in a two-dimensional cavity is numerically studied. Part of a compressible fluid (Helium) near the center line of the cavity is suddenly energized to generate pressure waves. Numerical solutions are secured by employing a highly accurate explicit method termed LCPFCT algorithm for the convection terms of the full Navier-Stokes equations. Thermoacoustic waves, which decay in large time due to the viscosity of fluid, are of the oscillatory nature. Much higher heat transfer rate can be achieved in an initial stage of transient processes, compared to that due to conduction. When a partial length of the cavity center line is heated, resulting thermoacoustic waves exhibit remarkable two-dimensional patterns.

  10. Progress report on LBL's numerical modeling studies on Cerro Prieto

    SciTech Connect (OSTI)

    Halfman-Dooley, S.E.; Lippman, M.J.; Bodvarsson, G.S.

    1989-04-01

    An exploitation model of the Cerro Prieto geothermal system is needed to assess the energy capacity of the field, estimate its productive lifetime and develop an optimal reservoir management plan. The model must consider the natural state (i.e., pre-exploitation) conditions of the system and be able to predict changes in the reservoir thermodynamic conditions (and fluid chemistry) in response to fluid production (and injection). This paper discusses the results of a three-dimensional numerical simulation of the natural state conditions of the Cerro Prieto field and compares computed and observed pressure and temperature/enthalpy changes for the 1973--1987 production period. 16 refs., 24 figs., 2 tabs.

  11. Development of Numerical Simulation Capabilities for In Situ Heating of Oil

    Office of Scientific and Technical Information (OSTI)

    Shale (Conference) | SciTech Connect Conference: Development of Numerical Simulation Capabilities for In Situ Heating of Oil Shale Citation Details In-Document Search Title: Development of Numerical Simulation Capabilities for In Situ Heating of Oil Shale Authors: Hoda, Nazish [1] ; Fang, Chen [1] ; Kelkar, Sharad [2] ; Pawar, Rajesh J. [2] + Show Author Affiliations ExxonMobil Upstream Research Company, Houston, TX, USA Los Alamos National Laboratory Publication Date: 2012-12-06 OSTI

  12. NUMERICAL STUDY OF THE VISHNIAC INSTABILITY IN SUPERNOVA REMNANTS

    SciTech Connect (OSTI)

    Michaut, C.; Cavet, C.; Bouquet, S. E.; Roy, F.; Nguyen, H. C.

    2012-11-10

    The Vishniac instability is thought to explain the complex structure of radiative supernova remnants in their Pressure-Driven Thin Shell (PDTS) phase after a blast wave (BW) has propagated from a central explosion. In this paper, the propagation of the BW and the evolution of the PDTS stage are studied numerically with the two-dimensional (2D) code HYDRO-MUSCL for a finite-thickness shell expanding in the interstellar medium (ISM). Special attention is paid to the adiabatic index, {gamma}, and three distinct values are taken for the cavity ({gamma}{sub 1}), the shell ({gamma}{sub 2}), and the ISM ({gamma}{sub 3}) with the condition {gamma}{sub 2} < {gamma}{sub 1}, {gamma}{sub 3}. This low value of {gamma}{sub 2} accounts for the high density in the shell achieved by a strong radiative cooling. Once the spherical background flow is obtained, the evolution of a 2D-axisymmetric perturbation is computed from the linear to the nonlinear regime. The overstable mechanism, previously demonstrated theoretically by E. T. Vishniac in 1983, is recovered numerically in the linear stage and is expected to produce and enhance anisotropies and clumps on the shock front, leading to the disruption of the shell in the nonlinear phase. The period of the increasing oscillations and the growth rate of the instability are derived from several points of view (the position of the perturbed shock front, mass fluxes along the shell, and density maps), and the most unstable mode differing from the value given by Vishniac is computed. In addition, the influence of several parameters (the Mach number, amplitude and wavelength of the perturbation, and adiabatic index) is examined and for wavelengths that are large enough compared to the shell thickness, the same conclusion arises: in the late stage of the evolution of the radiative supernova remnant, the instability is dampened and the angular initial deformation of the shock front is smoothed while the mass density becomes uniform with the angle. As a result, our model shows that the supernova remnant returns to a stable evolution and the Vishniac instability does not lead to the fragmentation of the shock as predicted by the theory.

  13. Numerical studies of the radiant flash pyrolysis of cellulose

    SciTech Connect (OSTI)

    Kothari, V.; Antal, M.J. Jr.

    1983-01-01

    When biomass particles are heated very rapidly (temperatures greater than 1000 degrees/s) in an oxygen free environment, they undergo pyrolysis with the formation of little or no char. If concentrated solar energy is used to rapidly heat the particles their temperature may exceed that of the surrounding gaseous environment by several hundred degrees Celsius when pyrolysis occurs. This two temperature effect gives rise to the formation of high yields of syrups from the pyrolyzing biomass. Numerical exploration of the combined effects of heat and mass transfer on the radiative flash pyrolysis phenonmena are described in this paper. 12 references.

  14. Numerical studies of the radiant flash pyrolysis of cellulose

    SciTech Connect (OSTI)

    Kothari, V.; Antal, M.J.

    1983-01-01

    When biomass particles are heated very rapidly (>1000/sup 0/C/s) in an oxygen free environment, they undergo pyrolysis with the formation of little or no char. If concentrated solar energy is used to rapidly heat the particles, their temperature may exceed that of the surrounding gaseous environment by several hundred degrees Celsius when pyrolysis occurs. This ''two temperature'' effect gives rise to the formation of high yields of sirups from the pyrolyzing biomass. Interest in the selective formation of sirups during the radiative flash pyrolysis of biomass caused the authors to initiate numerical explorations of the combined effects of heat and mass transfer on the radiative flash pyrolysis phenomena. These explorations are described in this paper.

  15. Numerical Study of Velocity Shear Stabilization of 3D and Theoretical...

    Office of Scientific and Technical Information (OSTI)

    We studied the feasibility of resonantly driving GAMs in tokamaks. A numerical simulation ... Experimental implications of this were quantified. Theoretical support was provided for ...

  16. Numerical Study on GRB-Jet Formation in Collapsars

    SciTech Connect (OSTI)

    Nagataki, Shigehiro; /Kyoto U., Yukawa Inst., Kyoto /KIPAC, Menlo Park; Takahashi, Rohta; /Tokyo U.; Mizuta, Akira; /Garching, Max Planck Inst.; Takiwaki, Tomoya; /Tokyo U.

    2006-08-22

    Two-dimensional magnetohydrodynamic simulations are performed using the ZEUS-2D code to investigate the dynamics of a collapsar that generates a GRB jet, taking account of realistic equation of state, neutrino cooling and heating processes, magnetic fields, and gravitational force from the central black hole and self gravity. It is found that neutrino heating processes are not so efficient to launch a jet in this study. It is also found that a jet is launched mainly by B{sub {phi}} fields that are amplified by the winding-up effect. However, since the ratio of total energy relative to the rest mass energy in the jet is not so high as several hundred, we conclude that the jets seen in this study are not be a GRB jet. This result suggests that general relativistic effects, which are not included in this study, will be important to generate a GRB jet. Also, the accretion disk with magnetic fields may still play an important role to launch a GRB jet, although a simulation for much longer physical time {approx} 10-100 s is required to confirm this effect. It is shown that considerable amount of {sup 56}Ni is synthesized in the accretion disk. Thus there will be a possibility for the accretion disk to supply sufficient amount of {sup 56}Ni required to explain the luminosity of a hypernova. Also, it is shown that neutron-rich matter due to electron captures with high entropy per baryon is ejected along the polar axis. Moreover, it is found that the electron fraction becomes larger than 0.5 around the polar axis near the black hole by {nu}{sub e} capture at the region. Thus there will be a possibility that r-process and r/p-process nucleosynthesis occur at these regions. Finally, much neutrons will be ejected from the jet, which suggests that signals from the neutron decays may be observed as the delayed bump of the light curve of the afterglow or gamma-rays.

  17. Numerical studies of a plasma diode with external forcing

    SciTech Connect (OSTI)

    Rekaa, V. L.; Pecseli, H. L.; Trulsen, J. K.

    2012-08-15

    With reference to laboratory Q-machine studies we analyze the dynamics of a plasma diode under external forcing. Assuming a strong axial magnetic field, the problem is analyzed in one spatial dimension by a particle-in-cell code. The cathode is assumed to be operated in electron rich conditions, supplying an abundance of electrons. We compare different forcing schemes with the results obtained by solving the van der Pol equation. In one method of forcing we apply an oscillation in addition to the DC end plate bias and consider both amplitude and frequency variations. An alternative method of perturbation consists of modelling an absorbing grid at some internal position. Also in this case we can have a constant frequency with varying amplitude or alternatively an oscillation with chirped frequency but constant amplitude. We find that the overall features of the forced van der Pol equation are recovered, but the details in the plasma response need more attention to the harmonic responses, requiring extensions of the model equation. The analysis is extended by introducing collisional effects, where we emphasize charge exchange collisions of ions, since these processes usually have the largest cross sections and give significant modifications of the diode performance. In particular we find a reduction in oscillator frequency, although a linear scaling of the oscillation time with the system length remains also in this case.

  18. Numerical study of the Columbia high-beta device: Torus-II

    SciTech Connect (OSTI)

    Izzo, R.

    1981-01-01

    The ionization, heating and subsequent long-time-scale behavior of the helium plasma in the Columbia fusion device, Torus-II, is studied. The purpose of this work is to perform numerical simulations while maintaining a high level of interaction with experimentalists. The device is operated as a toroidal z-pinch to prepare the gas for heating. This ionization of helium is studied using a zero-dimensional, two-fluid code. It is essentially an energy balance calculation that follows the development of the various charge states of the helium and any impurities (primarily silicon and oxygen) that are present. The code is an atomic physics model of Torus-II. In addition to ionization, we include three-body and radiative recombination processes.

  19. Numerical Study of Velocity Shear Stabilization of 3D and Theoretical

    Office of Scientific and Technical Information (OSTI)

    Considerations for Centrifugally Confined Plasmas and Other Interchange-Limited Fusion Concepts (Technical Report) | SciTech Connect Numerical Study of Velocity Shear Stabilization of 3D and Theoretical Considerations for Centrifugally Confined Plasmas and Other Interchange-Limited Fusion Concepts Citation Details In-Document Search Title: Numerical Study of Velocity Shear Stabilization of 3D and Theoretical Considerations for Centrifugally Confined Plasmas and Other Interchange-Limited

  20. Comprehensive Mechanisms for Combustion Chemistry: An Experimental and Numerical Study with Emphasis on Applied Sensitivity Analysis

    SciTech Connect (OSTI)

    Dryer, Frederick L.

    2009-04-10

    This project was an integrated experimental/numerical effort to study pyrolysis and oxidation reactions and mechanisms for small-molecule hydrocarbon structures under conditions representative of combustion environments. The experimental aspects of the work were conducted in large-diameter flow reactors, at 0.3 to 18 atm pressure, 500 to 1100 K temperature, and 10-2 to 2 seconds reaction time. Experiments were also conducted to determine reference laminar flame speeds using a premixed laminar stagnation flame experiment and particle image velocimetry, as well as pressurized bomb experiments. Flow reactor data for oxidation experiments include: (1)adiabatic/isothermal species time-histories of a reaction under fixed initial pressure, temperature, and composition; to determine the species present after a fixed reaction time, initial pressure; (2)species distributions with varying initial reaction temperature; (3)perturbations of a well-defined reaction systems (e.g. CO/H2/O2 or H2/O2)by the addition of small amounts of an additive species. Radical scavenging techniques are applied to determine unimolecular decomposition rates from pyrolysis experiments. Laminar flame speed measurements are determined as a function of equivalence ratio, dilution, and unburned gas temperature at 1 atm pressure. Hierarchical, comprehensive mechanistic construction methods were applied to develop detailed kinetic mechanisms which describe the measurements and literature kinetic data. Modeling using well-defined and validated mechanisms for the CO/H2/Oxidant systems and perturbations of oxidation experiments by small amounts of additives were also used to derive absolute reaction rates and to investigate the compatibility of published elementary kinetic and thermochemical information. Numerical tools were developed and applied to assess the importance of individual elementary reactions to the predictive performance of the developed mechanisms and to assess the uncertainties in elementary rate constant evaluations.

  1. Development of a Numerical Simulator for Analyzing the Geomechanical Performance of Hydrate-Bearing Sediments

    SciTech Connect (OSTI)

    Rutqvist, Jonny; Rutqvist, J.; Moridis, G.J.

    2008-06-01

    In this paper, we describe the development and application of a numerical simulator that analyzes the geomechanical performance of hydrate-bearing sediments, which may become an important future energy supply. The simulator is developed by coupling a robust numerical simulator of coupled fluid flow, hydrate thermodynamics, and phase behavior in geologic media (TOUGH+HYDRATE) with an established geomechanical code (FLAC3D). We demonstrate the current simulator capabilities and applicability for two examples of geomechanical responses of hydrate bearing sediments during production-induced hydrate dissociation. In these applications, the coupled geomechanical behavior within hydrate-bearing seducements are considered through a Mohr-Coulomb constitutive model, corrected for changes in pore-filling hydrate and ice content, based on laboratory data. The results demonstrate how depressurization-based gas production from oceanic hydrate deposits may lead to severe geomechanical problems unless care is taken in designing the production scheme. We conclude that the coupled simulator can be used to design production strategies for optimizing production, while avoiding damaging geomechanical problems.

  2. Numerical study of self modulation instability of 1 nC electron bunch at ATF

    SciTech Connect (OSTI)

    Fang Yun; Mori, Warren; Muggli, Patric

    2012-12-21

    The development of self-modulation instability (SMI) is investigated numerically for the 1 nC electron bunch available at Accelerator Test Facility (ATF) of Brookhaven National Laboratory (BNL). Possible experiment based on the simulation results is proposed. All the simulations are performed with the 2D-cylindrically symmetric particle-in-cell code.

  3. Recent advances in theoretical and numerical studies of wire array Z-pinch in the IAPCM

    SciTech Connect (OSTI)

    Ding, Ning Zhang, Yang Xiao, Delong Wu, Jiming Huang, Jun Yin, Li Sun, Shunkai Xue, Chuang Dai, Zihuan Ning, Cheng Shu, Xiaojian Wang, Jianguo Li, Hua

    2014-12-15

    Fast Z-pinch has produced the most powerful X-ray radiation source in laboratory and also shows the possibility to drive inertial confinement fusion (ICF). Recent advances in wire-array Z-pinch researches at the Institute of Applied Physics and Computational Mathematics are presented in this paper. A typical wire array Z-pinch process has three phases: wire plasma formation and ablation, implosion and the MRT instability development, stagnation and radiation. A mass injection model with azimuthal modulation coefficient is used to describe the wire initiation, and the dynamics of ablated plasmas of wire-array Z-pinches in (r, θ) geometry is numerically studied. In the implosion phase, a two-dimensional(r, z) three temperature radiation MHD code MARED has been developed to investigate the development of the Magneto-Rayleigh-Taylor(MRT) instability. We also analyze the implosion modes of nested wire-array and find that the inner wire-array is hardly affected before the impaction of the outer wire-array. While the plasma accelerated to high speed in the implosion stage stagnates on the axis, abundant x-ray radiation is produced. The energy spectrum of the radiation and the production mechanism are investigated. The computational x-ray pulse shows a reasonable agreement with the experimental result. We also suggest that using alloyed wire-arrays can increase multi-keV K-shell yield by decreasing the opacity of K-shell lines. In addition, we use a detailed circuit model to study the energy coupling between the generator and the Z-pinch implosion. Recently, we are concentrating on the problems of Z-pinch driven ICF, such as dynamic hohlraum and capsule implosions. Our numerical investigations on the interaction of wire-array Z-pinches on foam convertors show qualitative agreements with experimental results on the “Qiangguang I” facility. An integrated two-dimensional simulation of dynamic hohlraum driven capsule implosion provides us the physical insights of wire-array plasma acceleration, shock generation and production, hohlraum formation, radiation ablation and fuel compression.

  4. An approach for the development of an aerodynamic-structural interaction numerical simulation for aeropropulsion systems

    SciTech Connect (OSTI)

    Naziar, J.; Couch, R.; Davis, M.

    1996-01-01

    Traditionally, aeropropulsion structural performance and aerodynamic performance have been designed separately and later mated together via flight testing. In today`s atmosphere of declining resources, it is imperative that more productive ways of designing and verifying aeropropulsion performance and structural interaction be made available to the aerospace industry. One method of obtaining a more productive design and evaluation capability is through the use of numerical simulations. Currently, Lawrence Livermore National Laboratory has developed a generalized fluid/structural interaction code known as ALE3D. This code is capable of characterizing fluid and structural interaction for components such as the combustor, fan/stators, inlet and/or nozzles. This code solves the 3D Euler equations and has been applied to several aeropropulsion applications such as a supersonic inlet and a combustor rupture simulation. To characterize aerodynamic-structural interaction for rotating components such as the compressor, appropriate turbomachinery simulations would need to be implemented within the ALE3D structure. The Arnold Engineering Development Center is currently developing a three-dimensional compression system code known as TEACC (Turbine Engine Analysis Compressor Code). TEACC also solves the 3D Euler equations and is intended to simulate dynamic behavior such as inlet distortion, surge or rotating stall. The technology being developed within the TEACC effort provides the necessary turbomachinery simulation for implementation into ALE3D. This paper describes a methodology to combine three-dimensional aerodynamic turbomachinery technology into the existing aerodynamic-structural interaction simulation, ALE3D to obtain the desired aerodynamic and structural integrated simulation for an aeropropulsion system.

  5. PROBABILISTIC SIMULATION OF SUBSURFACE FLUID FLOW: A STUDY USING A NUMERICAL SCHEME

    SciTech Connect (OSTI)

    Buscheck, Timothy Eric

    1980-03-01

    There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeologic parameter, given a particular scale of interest. However, physically there is no such entity as a truly uniform and homogeneous unit. Single-number representations or deterministic predictions are subject to uncertainties. The approach used in this work models such uncertainties with probabilistic parameters. The resulting statistical distributions of output variables are analyzed. A numerical algorithm, based on axiomatic principles of probability theory, performs arithmetic operations between probability distributions. Two subroutines are developed from the algorithm and incorporated into the computer program TERZAGI, which solves groundwater flow problems in saturated, multi-dimensional systems. The probabilistic computer program is given the name, PROGRES. The algorithm has been applied to study the following problems: one-dimensional flow through homogeneous media, steady-state and transient flow conditions, one-dimensional flow through heterogeneous media, steady-state and transient flow conditions, and two-dimensional steady-stte flow through heterogeneous media. The results are compared with those available in the literature.

  6. Evolution of turbulence in the expanding solar wind, a numerical study

    SciTech Connect (OSTI)

    Dong, Yue; Grappin, Roland; Verdini, Andrea E-mail: verdini@arcetri.astro.it

    2014-10-01

    We study the evolution of turbulence in the solar wind by solving numerically the full three-dimensional (3D) magnetohydrodynamic (MHD) equations embedded in a radial mean wind. The corresponding equations (expanding box model or EBM) have been considered earlier but never integrated in 3D simulations. Here, we follow the development of turbulence from 0.2 AU up to about 1.5 AU. Starting with isotropic spectra scaling as k {sup –1}, we observe a steepening toward a k {sup –5/3} scaling in the middle of the wave number range and formation of spectral anisotropies. The advection of a plasma volume by the expanding solar wind causes a non-trivial stretching of the volume in directions transverse to radial and the selective decay of the components of velocity and magnetic fluctuations. These two effects combine to yield the following results. (1) Spectral anisotropy: gyrotropy is broken, and the radial wave vectors have most of the power. (2) Coherent structures: radial streams emerge that resemble the observed microjets. (3) Energy spectra per component: they show an ordering in good agreement with the one observed in the solar wind at 1 AU. The latter point includes a global dominance of the magnetic energy over kinetic energy in the inertial and f {sup –1} range and a dominance of the perpendicular-to-the-radial components over the radial components in the inertial range. We conclude that many of the above properties are the result of evolution during transport in the heliosphere, and not just the remnant of the initial turbulence close to the Sun.

  7. Precarious Rock Methodology for Seismic Hazard: Physical Testing, Numerical Modeling and Coherence Studies

    SciTech Connect (OSTI)

    Anooshehpoor, Rasool; Purvance, Matthew D.; Brune, James N.; Preston, Leiph A.; Anderson, John G.; Smith, Kenneth D.

    2006-09-29

    This report covers the following projects: Shake table tests of precarious rock methodology, field tests of precarious rocks at Yucca Mountain and comparison of the results with PSHA predictions, study of the coherence of the wave field in the ESF, and a limited survey of precarious rocks south of the proposed repository footprint. A series of shake table experiments have been carried out at the University of Nevada, Reno Large Scale Structures Laboratory. The bulk of the experiments involved scaling acceleration time histories (uniaxial forcing) from 0.1g to the point where the objects on the shake table overturned a specified number of times. The results of these experiments have been compared with numerical overturning predictions. Numerical predictions for toppling of large objects with simple contact conditions (e.g., I-beams with sharp basal edges) agree well with shake-table results. The numerical model slightly underpredicts the overturning of small rectangular blocks. It overpredicts the overturning PGA for asymmetric granite boulders with complex basal contact conditions. In general the results confirm the approximate predictions of previous studies. Field testing of several rocks at Yucca Mountain has approximately confirmed the preliminary results from previous studies, suggesting that he PSHA predictions are too high, possibly because the uncertainty in the mean of the attenuation relations. Study of the coherence of wavefields in the ESF has provided results which will be very important in design of the canisters distribution, in particular a preliminary estimate of the wavelengths at which the wavefields become incoherent. No evidence was found for extreme focusing by lens-like inhomogeneities. A limited survey for precarious rocks confirmed that they extend south of the repository, and one of these has been field tested.

  8. Numerical simulation study on fluid dynamics of plasma window using argon

    SciTech Connect (OSTI)

    Huang, S.; Zhu, K.; Shi, B. L.; Lu, Y. R.; Hershcovitch, A.; Yang, L.; Zhang, X. Y.; Wei, G. D.

    2013-07-15

    In this paper, a numerical 2D FLUENT-based magneto-hydrodynamic model has been developed to investigate the arc and flow field of plasma window, which is used as a windowless vacuum sealing device. The gas inlet, arc creation-developing and plasma expansion segments are all incorporated together in the integral model. An axis-symmetry cathode structure (hollow cathode) is used in the model. Current distribution of the arc is presented and discussed. The temperature, velocity, and pressure field are presented to show the physical mechanisms for the high pressure gap within the plasma window. Flow acceleration and viscosity effect are concluded as the main reasons for the pressure drop. The result for the pressure distribution in the cylindrical tube section has a good agreement with the analytical model. The validation for the sealing ability of plasma window is verified.

  9. Numerical studies of third-harmonic generation in laser filament in air perturbed by plasma spot

    SciTech Connect (OSTI)

    Feng Liubin; Lu Xin; Liu Xiaolong; Li Yutong; Chen Liming; Ma Jinglong; Dong Quanli; Wang Weimin; Xi Tingting; Sheng Zhengming; Zhang Jie; He Duanwei

    2012-07-15

    Third-harmonic emission from laser filament intercepted by plasma spot is studied by numerical simulations. Significant enhancement of the third-harmonic generation is obtained due to the disturbance of the additional plasma. The contribution of the pure plasma effect and the possible plasma-enhanced third-order susceptibility on the third-harmonic generation enhancement are compared. It is shown that the plasma induced cancellation of destructive interference [Y. Liu et al., Opt. Commun. 284, 4706 (2011)] of two-colored filament is the dominant mechanism of the enhancement of third-harmonic generation.

  10. Numerical study on microwave-sustained argon discharge under atmospheric pressure

    SciTech Connect (OSTI)

    Yang, Y.; Hua, W. Guo, S. Y.

    2014-04-15

    A numerical study on microwave sustained argon discharge under atmospheric pressure is reported in this paper. The purpose of this study is to investigate both the process and effects of the conditions of microwave-excited gas discharge under atmospheric pressure, thereby aiding improvements in the design of the discharge system, setting the appropriate working time, and controlling the operating conditions. A 3D model is presented, which includes the physical processes of electromagnetic wave propagation, electron transport, heavy species transport, gas flow, and heat transfer. The results can be obtained by means of the fluid approximation. The maxima of the electron density and gas temperature are 4.96 × 10{sup 18} m{sup −3} and 2514.8 K, respectively, and the gas pressure remains almost unchanged for typical operating conditions with a gas flow rate of 20 l/min, microwave power of 1000 W, and initial temperature of 473 K. In addition, the conditions (microwave power, gas flow rate, and initial temperature) of discharge are varied to obtain deeper information about the electron density and gas temperature. The results of our numerical study are valid and clearly describe both the physical process and effects of the conditions of microwave-excited argon discharge.

  11. Numerical study on coupled fluid flow and heat transfer process in parabolic trough solar collector tube

    SciTech Connect (OSTI)

    Tao, Y.B.; He, Y.L.

    2010-10-15

    A unified two-dimensional numerical model was developed for the coupled heat transfer process in parabolic solar collector tube, which includes nature convection, forced convection, heat conduction and fluid-solid conjugate problem. The effects of Rayleigh number (Ra), tube diameter ratio and thermal conductivity of the tube wall on the heat transfer and fluid flow performance were numerically analyzed. The distributions of flow field, temperature field, local Nu and local temperature gradient were examined. The results show that when Ra is larger than 10{sup 5}, the effects of nature convection must be taken into account. With the increase of tube diameter ratio, the Nusselt number in inner tube (Nu{sub 1}) increases and the Nusselt number in annuli space (Nu{sub 2}) decreases. With the increase of tube wall thermal conductivity, Nu{sub 1} decreases and Nu{sub 2} increases. When thermal conductivity is larger than 200 W/(m K), it would have little effects on Nu and average temperatures. Due to the effect of the nature convection, along the circumferential direction (from top to down), the temperature in the cross-section decreases and the temperature gradient on inner tube surface increases at first. Then, the temperature and temperature gradients would present a converse variation at {theta} near {pi}. The local Nu on inner tube outer surface increases along circumferential direction until it reaches a maximum value then it decreases again. (author)

  12. Numerical simulation to study the transient self focusing of laser beam in plasma

    SciTech Connect (OSTI)

    Sharma, R. P.; Hussain, Saba Gaur, Nidhi

    2015-02-15

    In this paper, we present the numerical simulation for the coupled system of equations governing the dynamics of laser and Ion Acoustic Wave (IAW) in a collisionless plasma, when the coupling between the waves is through ponderomotive non-linearity. The nonlinear evolution of the laser beam is studied when the pump laser is perturbed by a periodic perturbation. By changing the perturbation wave number, we have studied its effect on the nonlinear evolution pattern of laser beam. In order to have a physical insight into the nonlinear dynamics of laser beam evolution in time and space, we have studied the laser and IAW spectra containing spatial harmonics. The magnitude of these harmonics changes with time and leads to time dependent localization of laser beam in spatial domain. The nonlinear dynamics of this localization is investigated in detail by using simulation and a semi-analytical model.

  13. New Mexico renewable development study

    SciTech Connect (OSTI)

    Toole, Gasper [Los Alamos National Laboratory; Bent, Russell [Los Alamos National Laboratory; Ewers, Mary [Los Alamos National Laboratory

    2010-09-17

    Since the early 1990s, Los Alamos National Laboratory (LANL) has applied electric grid models and simulation software to problems of national significance. This effort continues with a variety of other projects funded by the Department of Energy (DOE), other federal and state agencies and private companies. Critical to the success of these programs is the ability to integrate regional-scale models of the electric grid, to assess the propagation of grid impacts, and to present interactively the effect of potential mitigating actions required to stabilize the grid. All of these capabilities are applied in this study, to accomplish the following goals and objectives: (1) Develop an AC power flow model representing future conditions within New Mexico's electric grid, using commercial tools accepted by the utility industry; (2) Conduct a 'screening' analysis of options for accelerating potential renewable energy development through the addition of a statewide transmission collector system; (3) Estimate total revenue needed, jobs created (temporary and permanent) plus indirect and direct impacts to the state's economy; (4) Evaluate potential cost allocation methodology; and (5) Issue a project report that will provide information for policy direction by state regulators, project developers, and legislators.

  14. Numerical studies of the imaging properties of doubly focussing crystals and their application to ITER

    SciTech Connect (OSTI)

    Bitter, M.; Fraenkel, B.; Hill, K.W.; Hsuan, H.; von Goeler, S. )

    1995-01-01

    Line brightness calculations for the parameters at the International Thermonuclear Experimental Reactor (ITER) and results from recent experiments on the Tokamak Fusion Test Reactor (TFTR) indicate that time-resolved measurements of the central ion temperature and other central plasma parameters should be feasible on ITER with nonperturbing amounts of krypton. Since the measurements will have to be performed in the presence of high fluxes of 14-MeV neutrons from DT-fusion reactions, the size of windows, apertures and x-ray detectors must be as small as possible. Under these conditions, the use of doubly focussing crystals can significantly enhance the signal-to-noise ratio. This paper describes numerical studies of the focussing properties of spherically bent crystals and their application to ITER.

  15. Numerical renormalization-group study of a Kondo hole in a one-dimensional Kondo insulator

    SciTech Connect (OSTI)

    Yu, C.C.

    1996-12-01

    We have studied a Kondo hole in a one-dimensional Kondo insulator at half-filling using a density matrix formulation of the numerical renormalization group. The Kondo hole introduces midgap states. The spin density introduced by the hole is localized in the vicinity of the hole. It resides primarily in the {ital f} spins for small exchange coupling {ital J} and in the conduction spins for large {ital J}. We present results on the spin gap, charge gap, and neutral gap. The presence of the Kondo hole reduces the charge gap but not the spin gap relative to a Kondo insulator without defects. For small {ital J}, the spin gap is smaller than the charge gap, while for large {ital J}, the spin gap is larger than the charge gap. RKKY interactions are reduced by the Kondo hole as can be seen in the staggered susceptibility. {copyright} {ital 1996 The American Physical Society.}

  16. Numerical studies of the flux-to-current ratio method in the KIPT neutron source facility

    SciTech Connect (OSTI)

    Cao, Y.; Gohar, Y.; Zhong, Z.

    2013-07-01

    The reactivity of a subcritical assembly has to be monitored continuously in order to assure its safe operation. In this paper, the flux-to-current ratio method has been studied as an approach to provide the on-line reactivity measurement of the subcritical system. Monte Carlo numerical simulations have been performed using the KIPT neutron source facility model. It is found that the reactivity obtained from the flux-to-current ratio method is sensitive to the detector position in the subcritical assembly. However, if multiple detectors are located about 12 cm above the graphite reflector and 54 cm radially, the technique is shown to be very accurate in determining the k{sub eff} this facility in the range of 0.75 to 0.975. (authors)

  17. Numerical study on the stabilization of neoclassical tearing modes by electron cyclotron current drive

    SciTech Connect (OSTI)

    Wang, Xiaoguang; Zhang, Xiaodong; Wu, Bin; Zhu, Sizheng; Hu, Yemin

    2015-02-15

    It is well known that electron cyclotron current drive (ECCD) around the o-point of magnetic island along the plasma current direction can stabilize neoclassical tearing modes (NTMs) in tokamak devices. The effects of the radial misalignment between the island and the driven current, the phase misalignment, and the on-duty ratio for modulated current drive on NTM stabilization are studied numerically in this paper. A small radial misalignment is found to significantly decrease the stabilizing effect. When a sufficiently large phase misalignment occurs for the modulated ECCD, the stabilization effect is also reduced a lot. The optimal on-duty ratio of modulated ECCD to stabilize NTMs is found to be in the range of 60%–70%. A larger on-duty ratio than 50% could also mitigate the effect of phase misalignment if it is not too large. There is no benefit from modulation if the phase misalignment is larger than a threshold.

  18. Numerical studies of active current profile control in the reversed-field pinch

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Toroidal Viscosity for Tokamaks (Technical Report) | SciTech Connect Numerical Verification of Bounce Harmonic Resonances in Neoclassical Toroidal Viscosity for Tokamaks Citation Details In-Document Search Title: Numerical Verification of Bounce Harmonic Resonances in Neoclassical Toroidal Viscosity for Tokamaks This Letter presents the rst numerical veri cation for the bounce-harmonic (BH) resonance phenomena of the neoclassical transport in a tokamak perturbed by non-axisymmetric magnetic

  19. A numerical study of soot aggregate formation in a laminar coflow diffusion flame

    SciTech Connect (OSTI)

    Zhang, Q.; Thomson, M.J. [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8 (Canada); Guo, H.; Liu, F.; Smallwood, G.J. [Institute for Chemical Process and Environmental Technology, National Research Council of Canada, Building M-9, 1200 Montreal Road, Ottawa, Ontario, K1A 0R6 (Canada)

    2009-03-15

    Soot aggregate formation in a two-dimensional laminar coflow ethylene/air diffusion flame is studied with a pyrene-based soot model, a detailed sectional aerosol dynamics model, and a detailed radiation model. The chemical kinetic mechanism describes polycyclic aromatic hydrocarbon formation up to pyrene, the dimerization of which is assumed to lead to soot nucleation. The growth and oxidation of soot particles are characterized by the HACA surface mechanism and pyrene-soot surface condensation. The mass range of the solid soot phase is divided into thirty-five discrete sections and two equations are solved in each section to model the formation of the fractal-like soot aggregates. The coagulation model is improved by implementing the aggregate coagulation efficiency. Several physical processes that may cause sub-unitary aggregate coagulation efficiency are discussed. Their effects on aggregate structure are numerically investigated. The average number of primary soot particles per soot aggregate n{sub p} is found to be a strong function of the aggregate coagulation efficiency. Compared to the available experimental data, n{sub p} is well reproduced with a constant 20% aggregate coagulation efficiency. The predicted axial velocity, OH mole fraction, and C{sub 2}H{sub 2} mole fraction are validated against experimental data in the literature. Reasonable agreements are obtained. Finally, a sensitivity study of the effects of particle coalescence on soot volume fraction and soot aggregate nanostructure is conducted using a coalescence cutoff diameter method. (author)

  20. A numerical study of crack initiation in a bcc iron system based...

    Office of Scientific and Technical Information (OSTI)

    direct numerical results to the dynamic bifurcation theory R. Haberman, SIAM J. Appl. Math. 37, 69-106 (1979). Authors: Li, Xiantao, E-mail: xli@math.psu.edu 1 + Show Author...

  1. Numerical study of the stress state of a deformation twin in magnesium

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Arul Kumar, M.; Kanjarla, A. K.; Niezgoda, S. R.; Lebensohn, R. A.; Tomé, C. N.

    2014-11-26

    Here, we present a numerical study of the distribution of the local stress state associated with deformation twinning in Mg, both inside the twinned domain and in its immediate neighborhood, due to the accommodation of the twinning transformation shear. A full-field elastoviscoplastic formulation based on fast Fourier transformation is modified to include the shear transformation strain associated with deformation twinning. We performed two types of twinning transformation simulations with: (i) the twin completely embedded inside a single crystal and (ii) the twin front terminating at a grain boundary. We show that: (a) the resulting stress distribution is more strongly determinedmore » by the shear transformation than by the intragranular character of the twin or the orientation of the neighboring grain; (b) the resolved shear stress on the twin plane along the twin direction is inhomogeneous along the twin–parent interface; and (c) there are substantial differences in the average values of the shear stress in the twin and in the parent grain that contains the twin. We discuss the effect of these local stresses on twin propagation and growth, and the implications of our findings for the modeling of deformation twinning.« less

  2. Numerical study of the stress state of a deformation twin in magnesium

    SciTech Connect (OSTI)

    Arul Kumar, M.; Kanjarla, A. K.; Niezgoda, S. R.; Lebensohn, R. A.; Tomé, C. N.

    2014-11-26

    Here, we present a numerical study of the distribution of the local stress state associated with deformation twinning in Mg, both inside the twinned domain and in its immediate neighborhood, due to the accommodation of the twinning transformation shear. A full-field elastoviscoplastic formulation based on fast Fourier transformation is modified to include the shear transformation strain associated with deformation twinning. We performed two types of twinning transformation simulations with: (i) the twin completely embedded inside a single crystal and (ii) the twin front terminating at a grain boundary. We show that: (a) the resulting stress distribution is more strongly determined by the shear transformation than by the intragranular character of the twin or the orientation of the neighboring grain; (b) the resolved shear stress on the twin plane along the twin direction is inhomogeneous along the twin–parent interface; and (c) there are substantial differences in the average values of the shear stress in the twin and in the parent grain that contains the twin. We discuss the effect of these local stresses on twin propagation and growth, and the implications of our findings for the modeling of deformation twinning.

  3. Numerical study of transition to supersonic flows in the edge plasma

    SciTech Connect (OSTI)

    Goswami, Rajiv, E-mail: rajiv@ipr.res.in; Artaud, Jean-Franois; Imbeaux, Frdric [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar382428 (India)

    2014-07-15

    The plasma scrape-off layer (SOL) in a tokamak is characterized by ion flow down a long narrow flux tube terminating on a solid surface. The ion flow velocity along a magnetic field line can be equal to or greater than sonic at the entrance of a Debye sheath or upstream in the presheath. This paper presents a numerical study of the transition between subsonic and supersonics flows. A quasineutral one-dimensional (1D) fluid code has been used for modeling of plasma transport in the SOL along magnetic field lines, both in steady state and under transient conditions. The model uses coupled equations for continuity, momentum, and energy balance with ionization, radiation, charge exchange, and recombination processes. The recycled neutrals are described in the diffusion approximation. Standard Bohm sheath criterion is used as boundary conditions at the material surface. Three conditions conducive for the generation of supersonic flows in SOL plasmas have been explored. It is found that in steady state high (attached) and low (detached) divertor temperatures cases, the role of particle, momentum, and energy loss is critical. For attached case, the appearance of shock waves in the divertor region if the incoming plasma flow is supersonic and its effect on impurity retention is presented. In the third case, plasma expansion along the magnetic field can yield time-dependent supersonic solutions in the quasineutral rarefaction wave. Such situations can arise in the parallel transport of intermittent structures such as blobs and edge localized mode filaments along field lines.

  4. Numerical study of oscillatory flow and heat transfer in a loaded thermoacoustic stack

    SciTech Connect (OSTI)

    Worlikar, A.S.; Knio, O.M.

    1999-01-01

    A thermoacoustic refrigerator may be idealized as consisting of a straight resonance tube housing a stack of parallel plates and heat exchangers, and an acoustic source. Among the advantages of thermoacoustic refrigerators are the simplicity of their design and the fact that they naturally avoid the need for harmful refrigerants such as chlorofluorocarbons (CFCs). The operation of these devices is based on exploiting the well-known thermoacoustic effect to induce a temperature difference across the stack and to transport heat from one end of the plate to the other. Heat exchangers are then used to transfer energy from the thermoacoustic refrigerator to hot and cold reservoirs. A two-dimensional, low-Mach-number computational model is used to analyze the unsteady flow and temperature fields in the neighborhood of an idealized stack/heat exchanger configuration. The model relies on a vorticity-based formulation of the mass, momentum, and energy equations in the low-Mach-number, short-stack limit. The stack and heat exchangers are assumed to consist of flat plates of equal thickness. The heat exchanger plates are assumed isothermal and in perfect thermal contact with the stack plates. The simulations are used to study the effect of heat exchanger size and operating conditions on the heat transfer and stack performance. Computed results show that optimum stack performance is achieved when the length of the heat exchanger is nearly equal to the peak-to-peak particle displacement. Numerical estimates of the mean enthalpy flux within the channel are in good agreement with the predictions of linear theory. However, the results reveal that a portion of the heat exchangers is ineffective due to reverse heat transfer. Details of the energy flux density around the heat exchangers are visualized, and implications regarding heat exchanger design and model extension are discussed.

  5. Numerical study of the effect of oxygenated blending compounds on soot formation in shock tubes

    SciTech Connect (OSTI)

    Boehm, H.; Braun-Unkhoff, M.

    2008-04-15

    This numerical study deals with the influence of blends on the amount of soot formed in shock tubes, which were simulated by assuming a homogeneous plug flow reactor model. For this purpose, first, the reaction model used here was validated against experimental results previously obtained in the literature. Then, the soot volume fractions of various mixtures of methyl tert-butyl ether (MTBE)-benzene, isobutene-benzene, methanol-benzene, and ethanol-benzene diluted in argon were simulated and compared to the results of benzene-argon pyrolysis at 1721 K and 5.4 MPa. For MTBE, isobutene, methanol, and ethanol, small amounts of additives to benzene-argon mixtures promoted soot formation, for the shock tube model assumed, while higher concentrations of these additives led to smaller soot volume fractions in comparison to pure benzene-argon pyrolysis. The most significant soot promotion effect was found for the additives MTBE and isobutene. The channel for MTBE decomposition producing isobutene and methanol is very effective at temperatures beyond 1200 K. Thus, both MTBE-benzene and isobutene-benzene mixtures diluted in argon showed rather similar behavior in regard to soot formation. Special emphasis was directed toward the causes for the concentration-dependent influence of the blends on the amount of soot formed. Aromatic hydrocarbons and acetylene were identified as key gas-phase species that determine the trends in the formation of soot of various mixtures. From reaction flux analysis for phenanthrene, it was deduced that the combinative routes including phenyl species play a major role in forming PAHs, especially at early reaction times. It is found that the additives play an important role in providing material to grow side chains, such as by reaction channels including phenylacetylene or benzyl, which are confirmed to form aromatic hydrocarbons and thus to influence the amount of soot formed, particularly when the concentrations of the blends are increased. (author)

  6. A NUMERICAL STUDY OF DIFFUSIVE COSMIC-RAY TRANSPORT WITH ADIABATIC FOCUSING

    SciTech Connect (OSTI)

    Litvinenko, Yuri E.; Noble, P. L.

    2013-03-01

    Focused particle transport in a nonuniform large-scale magnetic field is investigated numerically in the case of isotropic pitch-angle scattering. Evolving particle density profiles and distribution moments are computed from solutions of a system of stochastic differential equations, equivalent to the original Fokker-Planck equation for the particle distribution. Conflicting analytical predictions for the transport coefficients in the diffusion limit, independently calculated by Beeck and Wibberenz and Shalchi, are compared with the numerical results. The reasons for the discrepancies among the analytical and numerical treatments, as well as the general limitations of the diffusion model, are discussed. The telegraph equation, derived in a higher-order expansion of the particle distribution function, is shown to describe the particle transport much more accurately than the diffusion model, especially ahead of a moving density pulse.

  7. Discrete kinetic eigenmode spectra of electron plasma oscillations in weakly collisional plasma: A numerical study

    SciTech Connect (OSTI)

    Black, Carrie; Ng, C. S.

    2013-01-15

    It has been demonstrated that in the presence of weak collisions, described by the Lenard-Bernstein (LB) collision operator, the Landau-damped solutions become true eigenmodes of the system and constitute a complete set [C.-S. Ng et al., Phys. Rev. Lett. 83, 1974 (1999) and C. S. Ng et al., Phys. Rev. Lett. 96, 065002 (2004)]. We present numerical results from an Eulerian Vlasov code that incorporates the Lenard-Bernstein collision operator [A. Lenard and I. B. Bernstein, Phys. Rev. 112, 1456 (1958)]. The effect of collisions on the numerical recursion phenomenon seen in Vlasov codes is discussed. The code is benchmarked against exact linear eigenmode solutions in the presence of weak collisions, and a spectrum of Landau-damped solutions is determined within the limits of numerical resolution. Tests of the orthogonality and the completeness relation are presented.

  8. Experimental and numerical study of gas dynamic window for electron beam transport into the space with increased pressure

    SciTech Connect (OSTI)

    Skovorodko, P. A.; Sharafutdinov, R. G.

    2014-12-09

    The paper is devoted to experimental and numerical study of the gas jet technical device for obtaining axisymmetric flow with low pressure in its near axis region. The studied geometry of the device is typical of that used in the plasma generator consisting of an electron gun with a hollow (plasma) cathode and a double supersonic ring nozzle. The geometry of the nozzles as well as the relation between the gas flow rates through the nozzles providing the electron beam extraction into the region with increased pressure are tested both experimentally and numerically. The maximum external pressure of about 0.25 bar that does not disturb the electron beam is achieved.

  9. Numerical and Experimental Study of Mixing Processes Associated with Hydrogen and High Hydrogen Content Fuels

    SciTech Connect (OSTI)

    McDonell, Vincent; Hill, Scott; Akbari, Amin; McDonell, Vincent

    2011-09-30

    As simulation capability improves exponentially with increasingly more cost effective CPUs and hardware, it can be used ?routinely? for engineering applications. Many commercial products are available and they are marketed as increasingly powerful and easy to use. The question remains as to the overall accuracy of results obtained. To support the validation of the CFD, a hierarchical experiment was established in which the type of fuel injection (radial, axial) as well as level of swirl (non-swirling, swirling) could be systematically varied. The effort was limited to time efficient approaches (i.e., generally RANS approaches) although limited assessment of time resolved methods (i.e., unsteady RANS and LES) were considered. Careful measurements of the flowfield velocity and fuel concentration were made using both intrusive and non-intrusive methods. This database was then used as the basis for the assessment of the CFD approach. The numerical studies were carried out with a statistically based matrix. As a result, the effect of turbulence model, fuel type, axial plane, turbulent Schmidt number, and injection type could be studied using analysis of variance. The results for the non-swirling cases could be analyzed as planned, and demonstrate that turbulence model selection, turbulence Schmidt number, and the type of injection will strongly influence the agreement with measured values. Interestingly, the type of fuel used (either hydrogen or methane) has no influence on the accuracy of the simulations. For axial injection, the selection of proper turbulence Schmidt number is important, whereas for radial injection, the results are relatively insensitive to this parameter. In general, it was found that the nature of the flowfield influences the performance of the predictions. This result implies that it is difficult to establish a priori the ?best? simulation approach to use. However, the insights from the relative orientation of the jet and flow do offer some guidance for which approach to take. Overall, the results underscore the importance of model ?anchoring? (i.e., ?tuning? the model to provide ?reasonable? agreement with a well characterized geometry/flow). Finally, the results obtained have been carefully compiled into a standalone database following a standard format that is contained in an Appendix. This database is thus available for use by others for CFD modeling evaluations.

  10. Numerical Studies of Collective Phenomena in Two-Dimensional Electron and Cold Atom Systems

    SciTech Connect (OSTI)

    Rezayi, Edward

    2013-07-25

    Numerical calculations were carried out to investigate a number of outstanding questions in both two-dimensional electron and cold atom systems. These projects aimed to increase our understanding of the properties of and prospects for non-Abelian states in quantum Hall matter.

  11. A numerical study of geometry dependent errors in velocity, temperature, and density measurements from single grid planar retarding potential analyzers

    SciTech Connect (OSTI)

    Davidson, R. L.; Earle, G. D.; Heelis, R. A.; Klenzing, J. H.

    2010-08-15

    Planar retarding potential analyzers (RPAs) have been utilized numerous times on high profile missions such as the Communications/Navigation Outage Forecast System and the Defense Meteorological Satellite Program to measure plasma composition, temperature, density, and the velocity component perpendicular to the plane of the instrument aperture. These instruments use biased grids to approximate ideal biased planes. These grids introduce perturbations in the electric potential distribution inside the instrument and when unaccounted for cause errors in the measured plasma parameters. Traditionally, the grids utilized in RPAs have been made of fine wires woven into a mesh. Previous studies on the errors caused by grids in RPAs have approximated woven grids with a truly flat grid. Using a commercial ion optics software package, errors in inferred parameters caused by both woven and flat grids are examined. A flat grid geometry shows the smallest temperature and density errors, while the double thick flat grid displays minimal errors for velocities over the temperature and velocity range used. Wire thickness along the dominant flow direction is found to be a critical design parameter in regard to errors in all three inferred plasma parameters. The results shown for each case provide valuable design guidelines for future RPA development.

  12. Contribution to the numerical study of turbulence in high intensity discharge lamps

    SciTech Connect (OSTI)

    Kaziz, S.; Ben Ahmed, R.; Helali, H.; Gazzah, H.; Charrada, K. [Unite d'Etude des Milieux Ionises et Reactifs, IPEIM, 5019 route de Kairouan Monastir (Tunisia)

    2011-07-15

    We present in this paper a comparison between results obtained with a laminar and turbulent models for high-pressure mercury arc. The two models are based on the resolution of bidimensional time-dependent equations by a semi-implicit finite-element code. The numerical computation of turbulent model is solved with large eddy simulation model; this approach takes into account the various scales of turbulence by a filtering method on each scale. The results show the quantitative influence of turbulence on the flow fields and also the difference between laminar and turbulent effects on the dynamic thermal behaviour and on the characteristics of the discharge.

  13. LBNL Developing Countries Studies | Open Energy Information

    Open Energy Info (EERE)

    Global Climate, 1989 Organized and led studies of 12 developing countries on mitigation costs and emissions scenarios, 1991 and 1994 Special Issues of Energy Policy Technical...

  14. Numerical study on the influence of electron cyclotron current drive on tearing mode

    SciTech Connect (OSTI)

    Chen, Long; Liu, Jinyuan; Mao, Aohua; Sun, Jizhong, E-mail: jsun@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Duan, Ping [Department of Physics, Dalian Maritime University, Dalian 116026 (China)

    2014-10-15

    Controlling tearing modes by localized current drive is explored by using numerical simulation with a set of compressible magnetohydrodynamics equations. By examining the effects of different characteristics of driven current, such as density distribution, duration time, and deposition location, it is found that a driven current with larger magnitude and more focused deposition region shows a better suppression effect on the tearing modes. Meanwhile destabilizing effects are also observed when a driven current over a certain magnitude is applied continuously. In comparison with those on the X-point of the magnetic island, the results are better when the current deposition is targeted on the O-point. In addition, the timing control of the current deposition will be also addressed.

  15. Numerical study of nucleation and growth of bubbles in viscous magmas

    SciTech Connect (OSTI)

    Toramaru, A.

    1995-02-01

    The nucleation and growth processes of bubbles in viscous magmas with a constant decompression rate have been numerically investigated based on a formation which accounts for effects of viscosity, as well as diffusivity, interfacial tension, and decompression rate. The numerical solutions show two regimes in the nucleation and growth process, a diffusion-controlled regime and a viscosity-controlled regime, mainly depending on the decompression rate, initial saturation pressure and viscosity. The basic mechanism common to both regimes is that growth governs nucleation through depletion of degassing components. In basaltic eruptions the vesiculation is essentially controlled by diffusion, and the viscosity-controlled regime is limited to very high decompression rate and very small water content. When andesitic magma saturated by water at 10 MPa is decompressed through the propagation of rarefraction wave induced by a landslide, as took place in the Mount St. Helens 1980 eruption, the vesiculation is controlled by the viscosity up to 100 m depth. On the other hand, in a rhyolitic magma for the same situation, vesiculation is controlled by the viscosity over the whole depth of the magma column. In the viscosity-controlled regime, the vesicularity may be 90% or less as seen in silicic pumice, whereas in the diffusion-controlled regime the vesicularity equals or exceeds 98% such as in reticulite in Hawaiian basalt. An observed variation of the number density of bubbles by several orders of magnitude in plinian eruptions and the correlation with the SiO2 content can be attributed approximately to the dependence of diffusivity of viscosity on SiO2 content and temperature, assuming the apparent correlation between SiO2 content and temperature of magma.

  16. Numerical Study on Crossflow Printed Circuit Heat Exchanger for Advanced Small Modular Reactors

    SciTech Connect (OSTI)

    Yoon, Su-Jong; Sabharwall, Piyush; Kim, Eung-Soo

    2014-03-01

    Various fluids such as water, gases (helium), molten salts (FLiNaK, FLiBe) and liquid metal (sodium) are used as a coolant of advanced small modular reactors (SMRs). The printed circuit heat exchanger (PCHE) has been adopted as the intermediate and/or secondary heat exchanger of SMR systems because this heat exchanger is compact and effective. The size and cost of PCHE can be changed by the coolant type of each SMR. In this study, the crossflow PCHE analysis code for advanced small modular reactor has been developed for the thermal design and cost estimation of the heat exchanger. The analytical solution of single pass, both unmixed fluids crossflow heat exchanger model was employed to calculate a two dimensional temperature profile of a crossflow PCHE. The analytical solution of crossflow heat exchanger was simply implemented by using built in function of the MATLAB program. The effect of fluid property uncertainty on the calculation results was evaluated. In addition, the effect of heat transfer correlations on the calculated temperature profile was analyzed by taking into account possible combinations of primary and secondary coolants in the SMR systems. Size and cost of heat exchanger were evaluated for the given temperature requirement of each SMR.

  17. Quantum chaos and statistical properties of energy levels: Numerical study of the hydrogen atom in a magnetic field

    SciTech Connect (OSTI)

    Delande, D.; Gay, J.C.

    1986-10-20

    The transition to chaos in ''the hydrogen atom in a magnetic field'' is numerically studied and shown to lead to well-defined signature on the energy-level fluctuations. Upon an increase in the energy, the calculated statistics evolve from Poisson to Gaussian orthogonal ensemble according to the regular or chaotic character of the classical motion. Several methods are employed to test the generic nature of these distributions.

  18. Numerical Study of Field-reversed Configurations: The Formation and Ion Spin-up

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; M. Yamada; C.D. Cothran; M.R. Brown; M.J. Schaffer

    2005-06-06

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs, and the new FRC formation method by counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good qualitative agreement with results from the SSX-FRC experiment. The simulations show formation of an FRC in about 20-30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects.

  19. Analytical and numerical study of the transverse Kelvin-Helmholtz instability in tokamak edge plasmas

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Myra, James R.; D'Ippolito, Daniel A.; Russell, David A.; Umansky, Maxim V.; Baver, Derek A.

    2016-04-11

    Sheared flows perpendicular to the magnetic field can be driven by the Reynolds stress or ion pressure gradient effects and can potentially influence the stability and turbulent saturation level of edge plasma modes. On the other hand, such flows are subject to the transverse Kelvin- Helmholtz (KH) instability. Here, the linear theory of KH instabilities is first addressed with an analytic model in the asymptotic limit of long wavelengths compared with the flow scale length. The analytic model treats sheared ExB flows, ion diamagnetism (including gyro-viscous terms), density gradients and parallel currents in a slab geometry, enabling a unified summarymore » that encompasses and extends previous results. In particular, while ion diamagnetism, density gradients and parallel currents each individually reduce KH growth rates, the combined effect of density and ion pressure gradients is more complicated and partially counteracting. Secondly, the important role of realistic toroidal geometry is explored numerically using an invariant scaling analysis together with the 2DX eigenvalue code to examine KH modes in both closed and open field line regions. For a typical spherical torus magnetic geometry, it is found that KH modes are more unstable at and just outside the separatrix as a result of the distribution of magnetic shear. Lastly implications for reduced edge turbulence modeling codes are discussed.« less

  20. Numerical study of mechanical behavior of ceramic composites under compression loading in the framework of movable cellular automaton method

    SciTech Connect (OSTI)

    Konovalenko, Igor S. Smolin, Alexey Yu. Konovalenko, Ivan S.; Promakhov, Vladimir V.; Psakhie, Sergey G.

    2014-11-14

    Movable cellular automaton method was used for investigating the mechanical behavior of ceramic composites under uniaxial compression. A 2D numerical model of ceramic composites based on oxides of zirconium and aluminum with different structural parameters was developed using the SEM images of micro-sections of a real composite. The influence of such structural parameters as the geometrical dimensions of layers, inclusions, and their spatial distribution in the sample, the volume content of the composite components and their mechanical properties (as well as the amount of zirconium dioxide that underwent the phase transformation) on the fracture, strength, deformation and dissipative properties was investigated.

  1. Development of a Two-fluid Drag Law for Clustered Particles using Direct Numerical Simulation and Validation through Experiments

    SciTech Connect (OSTI)

    Gokaltun, Seckin; Munroe, Norman; Subramaniam, Shankar

    2014-12-31

    This study presents a new drag model, based on the cohesive inter-particle forces, implemented in the MFIX code. This new drag model combines an existing standard model in MFIX with a particle-based drag model based on a switching principle. Switches between the models in the computational domain occur where strong particle-to-particle cohesion potential is detected. Three versions of the new model were obtained by using one standard drag model in each version. Later, performance of each version was compared against available experimental data for a fluidized bed, published in the literature and used extensively by other researchers for validation purposes. In our analysis of the results, we first observed that standard models used in this research were incapable of producing closely matching results. Then, we showed for a simple case that a threshold is needed to be set on the solid volume fraction. This modification was applied to avoid non-physical results for the clustering predictions, when governing equation of the solid granular temperate was solved. Later, we used our hybrid technique and observed the capability of our approach in improving the numerical results significantly; however, improvement of the results depended on the threshold of the cohesive index, which was used in the switching procedure. Our results showed that small values of the threshold for the cohesive index could result in significant reduction of the computational error for all the versions of the proposed drag model. In addition, we redesigned an existing circulating fluidized bed (CFB) test facility in order to create validation cases for clustering regime of Geldart A type particles.

  2. Numerical study of effect of secondary electron emission on discharge characteristics in low pressure capacitive RF argon discharge

    SciTech Connect (OSTI)

    Liu, Qian; Liu, Yue, E-mail: liuyue@dlut.edu.cn; Samir, Tagra; Ma, Zhaoshuai [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2014-08-15

    Based on the drift and diffusion approximation theory, a 1D fluid model on capacitively coupled RF argon glow discharge at low pressure is established to study the effect of secondary electron emission (SEE) on the discharge characteristics. The model is numerically solved by using a finite difference method and the numerical results are obtained. The numerical results indicate that when the SEE coefficient is larger, the plasma density is higher and the time of reaching steady state is longer. It is also found that the cycle-averaged electric field, electric potential, and electron temperature change a little as the SEE coefficient is increased. Moreover, the discharge characteristics in some nonequilibrium discharge processes with different SEE coefficients have been compared. The analysis shows that when the SEE coefficient is varied from 0.01 to 0.3, the cycle-averaged electron net power absorption, electron heating rate, thermal convective term, electron energy dissipation, and ionization all have different degrees of growth. While the electron energy dissipation and ionization are quite special, there appear two peaks near each sheath region in the discharge with a relatively larger SEE coefficient. In this case, the discharge is certainly operated in a hybrid ?-?-mode.

  3. Numerical studies of fluid-rock interactions in EnhancedGeothermal...

    Office of Scientific and Technical Information (OSTI)

    transmission fluid. Initial studies have suggested that COsub 2 will achieve larger rates of heat extraction, and can ... reservoir zone with anhydrous supercritical COsub 2. ...

  4. A numerical study comparing the combustion and emission characteristics of biodiesel with petrodiesel.

    SciTech Connect (OSTI)

    Som, S.; Longman, D.

    2011-04-01

    Combustion and emission characteristics of compression ignition engines strongly depend upon inner-nozzle flow and spray behavior. These processes control the fuel-air mixing, which in turn is critical for the combustion process. Previous studies by us highlighted the differences in the physical and chemical properties of petrodiesel and biodiesel, which significantly altered the inner-nozzle flow and spray structure. The current study is another step in this direction to gain a fundamental understanding on the influence of fuel properties on the combustion and emission characteristics of the compression ignition engine. n-Heptane and methyl butanoate were selected as surrogates for diesel and biodiesel fuels, respectively, because the chemical kinetic pathways were well-understood. Liquid length and flame lift-off length for diesel and biodiesel fuels were validated against data available in the literature. Liquid lengths were always higher for biodiesel because of its higher heat of vaporization, which resulted in increased interplay between spray and combustion processes under all conditions investigated. Ambient air entrainment was also lower for biodiesel mainly because of slower atomization and breakup. The mechanism for flame stabilization is further analyzed by estimating the turbulent burning velocity for both of the fuels. This analysis revealed that neither flame propagation nor isolated ignition kernels upstream and detached from high-temperature regions can be the mechanism for flame stabilization. Flame propagation speeds were observed to be similar for both fuels. Biodiesel predicted lower soot concentrations, which were also reflected in reduced C{sub 2}H{sub 2} mole fractions. Although prompt NO{sub x} was higher for biodiesel, total NO{sub x} was lower because of reduced thermal NO{sub x}. The ignition delay and NO{sub x} emissions predicted by these simulations do not agree with trends reported in the literature; hence, this study highlights the need for better fuel surrogates for diesel and biodiesel fuels.

  5. An analytical and numerical study of the nonlinear reflection at a stress-free surface

    SciTech Connect (OSTI)

    Romer, Anne Kim, Jin-Yeon; Jacobs, Laurence J.

    2015-03-31

    Implementation of the ultrasonic second harmonic generation has typically been restricted to simple setups such as through-transmission or Rayleigh surface waves. Recent research has evaluated the second harmonic waves generation in P- and SV- waves reflected from a stress-free surface to enable the single-sided interrogation of a specimen. This research considers the second harmonic generation in an aluminum specimen, which is analytically evaluated using an approach based on a perturbation method. Here, the model is chosen to mimic an experimental setup where the longitudinal wave is generated at oblique angle using a wedge transducer. Due to the mode conversion at the interface of the wedge and the specimen, it is necessary to evaluate longitudinal and shear waves, determining all second harmonic waves generated in the bulk and at the stress-free boundary. The theoretically developed model is then implemented in a commercial finite element code, COMSOL, using increasing fundamental wave amplitudes for different values of third order elastic constants. The results of this computational model verify the analytical approach and the proposed measurement setup, taking into account assumptions and approximations of the solution procedure. Furthermore, the computational model is used to draw important conclusions relevant to the experimental setup, including the need to avoid interaction with diffracted waves.

  6. Numerical Study of Three Dimensional Effects in Longitudinal Space-Charge Impedance

    SciTech Connect (OSTI)

    Halavanau, A.; Piot, P.

    2015-06-01

    Longitudinal space-charge (LSC) effects are generally considered as detrimental in free-electron lasers as they can seed instabilities. Such “microbunching instabilities” were recently shown to be potentially useful to support the generation of broadband coherent radiation pulses [1, 2]. Therefore there has been an increasing interest in devising accelerator beamlines capable of sustaining this LSC instability as a mechanism to produce a coherent light source. To date most of these studies have been carried out with a one-dimensional impedance model for the LSC. In this paper we use a N-body “Barnes-Hut” algorithm [3] to simulate the 3D space charge force in the beam combined with elegant [4] and explore the limitation of the 1D model often used

  7. Numerical Study of Gamma-Ray Burst Jet Formation in Collapsars

    SciTech Connect (OSTI)

    Nagataki, S.; /Kyoto U., Yukawa Inst., Kyoto /KIPAC, Menlo Park; Takahashi, R.; /Tokyo U.; Mizuta, A.; Takiwaki, T.; /Garching, Max Planck Inst. /Tokyo U.

    2007-06-08

    Two-dimensional MHD simulations are performed using the ZEUS-2D code to investigate the dynamics of a collapsar that generates a GRB jet, taking account of realistic equation of state, neutrino cooling and heating processes, magnetic fields, and gravitational force from the central black hole and self-gravity. It is found that neutrino heating processes are not efficient enough to launch a jet in this study. It is also found that a jet is launched mainly by B{sub {phi}} fields that are amplified by the winding-up effect. However, since the ratio of total energy relative to the rest-mass energy in the jet is not as high as several hundred, we conclude that the jets seen in this study are not GRB jets. This result suggests that general relativistic effects will be important to generating a GRB jet. Also, the accretion disk with magnetic fields may still play an important role in launching a GRB jet, although a simulation for much longer physical time ({approx}10-100 s) is required to confirm this effect. It is shown that a considerable amount of {sup 56}Ni is synthesized in the accretion disk. Thus, there will be a possibility for the accretion disk to supply the sufficient amount of {sup 56}Ni required to explain the luminosity of a hypernova. Also, it is shown that neutron-rich matter due to electron captures with high entropy per baryon is ejected along the polar axis. Thus, there will be a possibility that r-process nucleosynthesis occurs at such a region. Finally, many neutrons will be ejected from the jet, which suggests that signals from the neutron decays may be observed as the delayed bump of the light curve of the afterglow or gamma rays.

  8. Numerical Study of Coal Gasification Using Eulerian-Eulerian Multiphase Model

    SciTech Connect (OSTI)

    Shi, S.; Guenther, C.; Orsino, S.

    2007-09-01

    Gasification converts the carbon-containing material into a synthesis gas (syngas) which can be used as a fuel to generate electricity or used as a basic chemical building block for a large number of uses in the petrochemical and refining industries. Based on the mode of conveyance of the fuel and the gasifying medium, gasification can be classified into fixed or moving bed, fluidized bed, and entrained flow reactors. Entrained flow gasifiers normally feature dilute flow with small particle size and can be successfully modeled with the Discrete Phase Method (DPM). For the other types, the Eulerian-Eulerian (E-E) or the so called two-fluid multiphase model is a more appropriate approach. The E-E model treats the solid phase as a distinct interpenetrating granular fluid and it is the most general-purposed multi-fluid model. This approach provides transient, three-dimensional, detailed information inside the reactor which would otherwise be unobtainable through experiments due to the large scale, high pressure and/or temperature. In this paper, a transient, three-dimensional model of the Power Systems Development Facility (PSDF) transport gasifier will be presented to illustrate how Computational Fluid Dynamics (CFD) can be used for large-scale complicated geometry with detailed physics and chemistry. In the model, eleven species are included in the gas phase while four pseudo-species are assumed in the solid phase. A total of sixteen reactions, both homogeneous (involving only gas phase species) and heterogeneous (involving species in both gas and solid phases), are used to model the coal gasification chemistry. Computational results have been validated against PSDF experimental data from lignite to bituminous coals under both air and oxygen blown conditions. The PSDF gasifier geometry was meshed with about 70,000, hexahedra-dominated cells. A total of six cases with different coal, feed gas, and/or operation conditions have been performed. The predicted and measured temperature profiles along the gasifier and gas compositions at the outlet agreed fairly well.

  9. A numerical study of short residence time FCC riser flows with a new flow/kinetics modeling technique.

    SciTech Connect (OSTI)

    Chang, S. L.

    1998-08-25

    Fluid Catalytic Cracking (FCC) technology is the most important process used by the refinery industry to convert crude oil to valuable lighter products such as gasoline. New and modified processes are constantly developed by refinery companies to improve their global competitiveness and meet more stringent environmental regulations. Short residence time FCC riser reactor is one of the advanced processes that the refining industry is actively pursuing because it can improve the yield selectivity and efficiency of an FCC unit. However, as the residence time becomes shorter, the impact of the mixing between catalyst and feed oil at the feed injection region on the product yield becomes more significant. Currently, most FCC computer models used by the refineries perform sophisticated kinetic calculations on simplified flow field and can not be used to evaluate the impact of fluid mixing on the performance of an FCC unit. Argonne National Laboratory (AFL) is developing a computational fluid dynamic (CFD) code ICRKFLO for FCC riser flow modeling. The code, employing hybrid hydrodynamic-chemical kinetic coupling techniques, is used to investigate the effect of operating and design conditions on the product yields of FCC riser reactors. Numerical calculations were made using the code to examine the impacts of the operating and design conditions on the product yields. The controlling parameters under investigation include the residence time, reaction temperature, and catalyst/oil ratio. This paper describes the CFD code, presents computation results, and discusses the effects of operating conditions on the performance of short residence time FCC riser reactors.

  10. AFCI Safeguards Enhancement Study: Technology Development Roadmap

    SciTech Connect (OSTI)

    Smith, Leon E.; Dougan, A.; Tobin, Stephen; Cipiti, B.; Ehinger, Michael H.; Bakel, A. J.; Bean, Robert; Grate, Jay W.; Santi, P.; Bryan, Steven; Kinlaw, M. T.; Schwantes, Jon M.; Burr, Tom; Lehn, Scott A.; Tolk, K.; Chichester, David; Menlove, H.; Vo, D.; Duckworth, Douglas C.; Merkle, P.; Wang, T. F.; Duran, F.; Nakae, L.; Warren, Glen A.; Friedrich, S.; Rabin, M.

    2008-12-31

    The Advanced Fuel Cycle Initiative (AFCI) Safeguards Campaign aims to develop safeguards technologies and processes that will significantly reduce the risk of proliferation in the U.S. nuclear fuel cycle of tomorrow. The Safeguards Enhancement Study was chartered with identifying promising research and development (R&D) directions over timescales both near-term and long-term, and under safeguards oversight both domestic and international. This technology development roadmap documents recognized gaps and needs in the safeguarding of nuclear fuel cycles, and outlines corresponding performance targets for each of those needs. Drawing on the collective expertise of technologists and user-representatives, a list of over 30 technologies that have the potential to meet those needs was developed, along with brief summaries of each candidate technology. Each summary describes the potential impact of that technology, key research questions to be addressed, and prospective development milestones that could lead to a definitive viability or performance assessment. Important programmatic linkages between U.S. agencies and offices are also described, reflecting the emergence of several safeguards R&D programs in the U.S. and the reinvigoration of nuclear fuel cycles across the globe.

  11. Numerical modeling of carrier gas flow in atomic layer deposition vacuum reactor: A comparative study of lattice Boltzmann models

    SciTech Connect (OSTI)

    Pan, Dongqing; Chien Jen, Tien [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201 (United States); Li, Tao [School of Mechanical Engineering, Dalian University of Technology, Dalian 116024 (China); Yuan, Chris, E-mail: cyuan@uwm.edu [Department of Mechanical Engineering, University of Wisconsin-Milwaukee, 3200 North Cramer Street, Milwaukee, Wisconsin 53211 (United States)

    2014-01-15

    This paper characterizes the carrier gas flow in the atomic layer deposition (ALD) vacuum reactor by introducing Lattice Boltzmann Method (LBM) to the ALD simulation through a comparative study of two LBM models. Numerical models of gas flow are constructed and implemented in two-dimensional geometry based on lattice BhatnagarGrossKrook (LBGK)-D2Q9 model and two-relaxation-time (TRT) model. Both incompressible and compressible scenarios are simulated and the two models are compared in the aspects of flow features, stability, and efficiency. Our simulation outcome reveals that, for our specific ALD vacuum reactor, TRT model generates better steady laminar flow features all over the domain with better stability and reliability than LBGK-D2Q9 model especially when considering the compressible effects of the gas flow. The LBM-TRT is verified indirectly by comparing the numerical result with conventional continuum-based computational fluid dynamics solvers, and it shows very good agreement with these conventional methods. The velocity field of carrier gas flow through ALD vacuum reactor was characterized by LBM-TRT model finally. The flow in ALD is in a laminar steady state with velocity concentrated at the corners and around the wafer. The effects of flow fields on precursor distributions, surface absorptions, and surface reactions are discussed in detail. Steady and evenly distributed velocity field contribute to higher precursor concentration near the wafer and relatively lower particle velocities help to achieve better surface adsorption and deposition. The ALD reactor geometry needs to be considered carefully if a steady and laminar flow field around the wafer and better surface deposition are desired.

  12. Detecting breast microcalcifications using super-resolution and wave-equation ultrasound imaging: a numerical phantom study

    SciTech Connect (OSTI)

    Huang, Lianjie; Simonetti, Francesco; Huthwaite, Peter; Rosenberg, Robert; Williamson, Michael

    2010-01-01

    Ultrasound image resolution and quality need to be significantly improved for breast microcalcification detection. Super-resolution imaging with the factorization method has recently been developed as a promising tool to break through the resolution limit of conventional imaging. In addition, wave-equation reflection imaging has become an effective method to reduce image speckles by properly handling ultrasound scattering/diffraction from breast heterogeneities during image reconstruction. We explore the capabilities of a novel super-resolution ultrasound imaging method and a wave-equation reflection imaging scheme for detecting breast microcalcifications. Super-resolution imaging uses the singular value decomposition and a factorization scheme to achieve an image resolution that is not possible for conventional ultrasound imaging. Wave-equation reflection imaging employs a solution to the acoustic-wave equation in heterogeneous media to backpropagate ultrasound scattering/diffraction waves to scatters and form images of heterogeneities. We construct numerical breast phantoms using in vivo breast images, and use a finite-difference wave-equation scheme to generate ultrasound data scattered from inclusions that mimic microcalcifications. We demonstrate that microcalcifications can be detected at full spatial resolution using the super-resolution ultrasound imaging and wave-equation reflection imaging methods.

  13. Avian study protocols and wind energy development

    SciTech Connect (OSTI)

    Fisher, K.

    1995-12-01

    This paper identifies the need to develop and use standardized avian study protocols to determine avian impacts at new and existing wind energy facilities. This will allow data collected from various sites to be correlated for better understanding wind energy related avian impacts. Factors contributing to an increased interest in wind energy facilities by electric utilities include: (1) Increased demand for electricity;(2) increased constraints on traditional electrical generating facilities (i.e. hydroelectric and nuclear power plants);(3) improved wind turbine technology. During the 1980`s generous tax credits spawned the development of wind energy facilities, known as wind farms, in California. Commercial scale wind farm proposals are being actively considered in states across the country - Washington, Oregon, Wyoming, Wisconsin, Texas, and Vermont to name a few. From the wind farms in California the unexpected issue of avian impacts, especially to birds-of-prey, or raptor, surfaced and continues to plague the wind industry. However, most of the avian studies did not followed a standardized protocol or methodology and, therefore, data is unavailable to analyze and compare impacts at different sites or with differing technologies and configurations. Effective mitigation can not be designed and applied until these differences are understood. The Bonneville Power Administration is using comparable avian study protocols to collect data for two environmental impact statements being prepared for two separate wind farm proposals. Similar protocol will be required for any other avian impact analysis performed by the agency on proposed or existing wind farms. The knowledge gained from these studies should contribute to a better understanding of avian interactions with wind energy facilities and the identification of effective mitigation measures.

  14. Advanced Cell Development and Degradation Studies

    SciTech Connect (OSTI)

    J. E. O'Brien; C. M. Stoots; J. S. Herring; R. C. O'Brien; K. G. Condie; M. Sohal; G. K. Housley; J. J. Hartvigsen; D. Larsen; G. Tao; B. Yildiz; V. Sharma; P. Singh; N. Petigny; T. L. Cable

    2010-09-01

    The Idaho National Laboratory (INL) has been researching the application of solid-oxide electrolysis cells for large-scale hydrogen production from steam over a temperature range of 800 to 900ºC. From 2003 – 2009, this work was sponsored by the DOE Nuclear Hydrogen Initiative (NHI). Starting in 2010, the HTE research program has been sponsored by the Next Generation Nuclear Plant (NGNP) program. HTSE research priorities in FY10 are centered on understanding and reducing cell and stack performance degradation to an acceptable level to advance the technology readiness level of HTSE and to justify further large-scale demonstration activities. This report provides a summary of our FY10 experimental program, which has been focused on advanced cell and stack development and degradation studies. Advanced cell and stack development activities are under way at five technology partners: MSRI, Versa Power, Ceramatec, NASA Glenn, and St. Gobain. Performance evaluation of the advanced technology cells and stacks has been performed by the technology partners, by MIT and the University of Connecticut and at the INL HTE Laboratory. Summaries of these development activities and test results are presented.

  15. Mixture Preparation and Nitric Oxide Formation in a GDI Engine studied by Combined Laser Diagnostics and Numerical Modeling

    SciTech Connect (OSTI)

    Volker Sick; Dennis N. Assanis

    2002-11-27

    Through the combination of advanced imaging laser diagnostics with multi-dimensional computer models, a new understanding of the performance of direct-injection gasoline engines is pursuit. The work focuses on the fuel injection process, the breakup of the liquid into a fine spray and the mixing of the fuel with the in-cylinder gases. Non-intrusive laser diagnostics will be used to measure the spatial distribution of droplets and vaporized fuel with very high temporal resolution. These data along with temperature measurements will be used to validate a new spray breakup model for gasoline direct-injection. Experimental data on near wall fuel distributions will be used for comparison with a model that predicts the spray-wall interaction and the dynamics of the liquid film on the surface. Quantitative measurements of local nitric oxide concentrations inside the combustion chamber will provide a critical test for a numerical simulation of the nitric oxide formation process. This model is based on a modified flamelet approach and will be used to study the effects of exhaust gas recirculation.

  16. LBNL Developing Countries Studies | Open Energy Information

    Open Energy Info (EERE)

    in a number of activities relating to energy use in developing countries and climate change. Developed international energy use data and emissions scenarios for the EPA report to...

  17. Validation Studies for Numerical Simulations of Flow Phenomena Expected in the Lower Plenum of a Prismatic VHTR Reference Design

    SciTech Connect (OSTI)

    Richard W. Johnson

    2005-09-01

    The final design of the very high temperature reactor (VHTR) of the fourth generation of nuclear power plants (Gen IV) has not yet been established. The VHTR may be either a prismatic (block) or pebble bed type. It may be either gas-cooled or cooled with an as yet unspecified molten salt. However, a conceptual design of a gas-cooled VHTR, based on the General Atomics GT-MHR, does exist and is called the prismatic VHTR reference design, MacDonald et al [2003], General Atomics [1996]. The present validation studies are based on the prismatic VHTR reference design. In the prismatic VHTR reference design, the flow in the lower plenum will be introduced by dozens of turbulent jets issuing into a large crossflow that must negotiate dozens of cylindrical support columns as it flows toward the exit duct of the reactor vessel. The jets will not all be at the same temperature due to the radial variation of power density expected in the core. However, it is important that the coolant be well mixed when it enters the power conversion unit to ensure proper operation and long life of the power conversion machinery. Hence, it is deemed important to be able to accurately model the flow and mixing of the variable temperature coolant in the lower plenum and exit duct. Accurate flow modeling involves determining modeling strategies including the fineness of the grid needed, iterative convergence tolerance, numerical discretization method used, whether the flow is steady or unsteady, and the turbulence model and wall treatment employed. It also involves validation of the computer code and turbulence model against a series of separate and combined flow phenomena and selection of the data used for the validation. The present report describes progress made to date for the task entitled ‘CFD software validation of jets in crossflow’ which was designed to investigate the issues pertaining to the validation process.

  18. Indonesia-Low Carbon Development Options Study | Open Energy...

    Open Energy Info (EERE)

    Indonesia-Low Carbon Development Options Study (Redirected from ESMAP-Indonesia-Low Carbon Development Options Study) Jump to: navigation, search Name Indonesia-ESMAP Low Carbon...

  19. National Strategy Study on the Clean Development Mechanism in...

    Open Energy Info (EERE)

    Strategy Study on the Clean Development Mechanism in Indonesia Jump to: navigation, search Name National Strategy Study on the Clean Development Mechanism in Indonesia Agency...

  20. Development of Materials Analysis Tools for Studying NOx Adsorber...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Studying NOx Adsorber Catalysts A cooperative research and development agreement with Cummins Engine Company Development of Materials Analysis Tools for Studying NOx Adsorber ...

  1. DOE Zero Energy Ready Home Case Study: Weiss Building & Development...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Weiss Building & Development LLC, System Home, River Forest, IL DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC, System Home, River Forest, IL Case study of ...

  2. Study of Particle Rotation Effect in Gas-Solid Flows using Direct Numerical Simulation with a Lattice Boltzmann Method

    SciTech Connect (OSTI)

    Kwon, Kyung; Fan, Liang-Shih; Zhou, Qiang; Yang, Hui

    2014-09-30

    A new and efficient direct numerical method with second-order convergence accuracy was developed for fully resolved simulations of incompressible viscous flows laden with rigid particles. The method combines the state-of-the-art immersed boundary method (IBM), the multi-direct forcing method, and the lattice Boltzmann method (LBM). First, the multi-direct forcing method is adopted in the improved IBM to better approximate the no-slip/no-penetration (ns/np) condition on the surface of particles. Second, a slight retraction of the Lagrangian grid from the surface towards the interior of particles with a fraction of the Eulerian grid spacing helps increase the convergence accuracy of the method. An over-relaxation technique in the procedure of multi-direct forcing method and the classical fourth order Runge-Kutta scheme in the coupled fluid-particle interaction were applied. The use of the classical fourth order Runge-Kutta scheme helps the overall IB-LBM achieve the second order accuracy and provides more accurate predictions of the translational and rotational motion of particles. The preexistent code with the first-order convergence rate is updated so that the updated new code can resolve the translational and rotational motion of particles with the second-order convergence rate. The updated code has been validated with several benchmark applications. The efficiency of IBM and thus the efficiency of IB-LBM were improved by reducing the number of the Lagragian markers on particles by using a new formula for the number of Lagrangian markers on particle surfaces. The immersed boundary-lattice Boltzmann method (IBLBM) has been shown to predict correctly the angular velocity of a particle. Prior to examining drag force exerted on a cluster of particles, the updated IB-LBM code along with the new formula for the number of Lagrangian markers has been further validated by solving several theoretical problems. Moreover, the unsteadiness of the drag force is examined when a fluid is accelerated from rest by a constant average pressure gradient toward a steady Stokes flow. The simulation results agree well with the theories for the short- and long-time behavior of the drag force. Flows through non-rotational and rotational spheres in simple cubic arrays and random arrays are simulated over the entire range of packing fractions, and both low and moderate particle Reynolds numbers to compare the simulated results with the literature results and develop a new drag force formula, a new lift force formula, and a new torque formula. Random arrays of solid particles in fluids are generated with Monte Carlo procedure and Zinchenko's method to avoid crystallization of solid particles over high solid volume fractions. A new drag force formula was developed with extensive simulated results to be closely applicable to real processes over the entire range of packing fractions and both low and moderate particle Reynolds numbers. The simulation results indicate that the drag force is barely affected by rotational Reynolds numbers. Drag force is basically unchanged as the angle of the rotating axis varies.

  3. RAMONA-4B development for SBWR safety studies

    SciTech Connect (OSTI)

    Rohatgi, U.S.; Aronson, A.L.; Cheng, H.S.; Khan, H.J.; Mallen, A.N.

    1993-12-31

    The Simplified Boiling Water Reactor (SBWR) is a revolutionary design of a boiling-water reactor. The reactor is based on passive safety systems such as natural circulation, gravity flow, pressurized gas, and condensation. SBWR has no active systems, and the flow in the vessel is by natural circulation. There is a large chimney section above the core to provide a buoyancy head for natural circulation. The reactor can be shut down by either of four systems; namely, scram, Fine Motion Control Rod Drive (FMCRD), Alternate Rod Insertion (ARI), and Standby Liquid Control System (SLCS). The safety injection is by gravity drain from the Gravity Driven Cooling System (GDCS) and Suppression Pool (SP). The heat sink is through two types of heat exchangers submerged in the tank of water. These heat exchangers are the Isolation Condenser (IC) and the Passive Containment Cooling System (PCCS). The RAMONA-4B code has been developed to simulate the normal operation, reactivity transients, and to address the instability issues for SBWR. The code has a three-dimensional neutron kinetics coupled to multiple parallel-channel thermal-hydraulics. The two-phase thermal hydraulics is based on a nonhomogeneous nonequilibrium drift-flux formulation. It employs an explicit integration to solve all state equations (except for neutron kinetics) in order to predict the instability without numerical damping. The objective of this project is to develop a Sun SPARC and IBM RISC 6000 based RAMONA-4B code for applications to SBWR safety analyses, in particular for stability and ATWS studies.

  4. Using the OECD/NRC Pressurized Water Reactor Main Steam Line Break Benchmark to Study Current Numerical and Computational Issues of Coupled Calculations

    SciTech Connect (OSTI)

    Ivanov, Kostadin N.; Todorova, Nadejda K.; Sartori, Enrico

    2003-05-15

    Incorporating full three-dimensional (3-D) models of the reactor core into system transient codes allows for a 'best-estimate' calculation of interactions between the core behavior and plant dynamics. Recent progress in computer technology has made the development of coupled thermal-hydraulic (T-H) and neutron kinetics code systems feasible. Considerable efforts have been made in various countries and organizations in this direction. Appropriate benchmarks need to be developed that will permit testing of two particular aspects. One is to verify the capability of the coupled codes to analyze complex transients with coupled core-plant interactions. The second is to test fully the neutronics/T-H coupling. One such benchmark is the Pressurized Water Reactor Main Steam Line Break (MSLB) Benchmark problem. It was sponsored by the Organization for Economic Cooperation and Development, U.S. Nuclear Regulatory Commission, and The Pennsylvania State University. The benchmark problem uses a 3-D neutronics core model that is based on real plant design and operational data for the Three Mile Island Unit 1 nuclear power plant. The purpose of this benchmark is threefold: to verify the capability of system codes for analyzing complex transients with coupled core-plant interactions; to test fully the 3-D neutronics/T-H coupling; and to evaluate discrepancies among the predictions of coupled codes in best-estimate transient simulations. The purposes of the benchmark are met through the application of three exercises: a point kinetics plant simulation (exercise 1), a coupled 3-D neutronics/core T-H evaluation of core response (exercise 2), and a best-estimate coupled core-plant transient model (exercise 3).In this paper we present the three exercises of the MSLB benchmark, and we summarize the findings of the participants with regard to the current numerical and computational issues of coupled calculations. In addition, this paper reviews in some detail the sensitivity studies on exercises 2 and 3 performed by the benchmark team using the coupled code TRAC-PF1/NEM. The purpose of these supporting studies was to aid participants in developing their models.

  5. Numerical simulation studies of the long-term evolution of a CO2 plume in a saline aquifer with a sloping caprock

    SciTech Connect (OSTI)

    Pruess, K.; Nordbotten, J.

    2010-12-28

    We have used the TOUGH2-MP/ECO2N code to perform numerical simulation studies of the long-term behavior of CO{sub 2} stored in an aquifer with a sloping caprock. This problem is of great practical interest, and is very challenging due to the importance of multi-scale processes. We find that the mechanism of plume advance is different from what is seen in a forced immiscible displacement, such as gas injection into a water-saturated medium. Instead of pushing the water forward, the plume advances because the vertical pressure gradients within the plume are smaller than hydrostatic, causing the groundwater column to collapse ahead of the plume tip. Increased resistance to vertical flow of aqueous phase in anisotropic media leads to reduced speed of updip plume advancement. Vertical equilibrium models that ignore effects of vertical flow will overpredict the speed of plume advancement. The CO{sub 2} plume becomes thinner as it advances, yet the speed of advancement remains constant over the entire simulation period of up to 400 years, with migration distances of more than 80 km. Our simulations include dissolution of CO{sub 2} into the aqueous phase and associated density increase, and molecular diffusion. However, no convection develops in the aqueous phase because it is suppressed by the relatively coarse (sub-) horizontal gridding required in a regional-scale model. A first crude sub-grid-scale model was developed to represent convective enhancement of CO{sub 2} dissolution. This process is found to greatly reduce the thickness of the CO{sub 2} plume, but, for the parameters used in our simulations, does not affect the speed of plume advancement.

  6. A procedure for the estimation of the numerical uncertainty of CFD calculations based on grid refinement studies

    SciTech Connect (OSTI)

    Ea, L.; Hoekstra, M.

    2014-04-01

    This paper offers a procedure for the estimation of the numerical uncertainty of any integral or local flow quantity as a result of a fluid flow computation; the procedure requires solutions on systematically refined grids. The error is estimated with power series expansions as a function of the typical cell size. These expansions, of which four types are used, are fitted to the data in the least-squares sense. The selection of the best error estimate is based on the standard deviation of the fits. The error estimate is converted into an uncertainty with a safety factor that depends on the observed order of grid convergence and on the standard deviation of the fit. For well-behaved data sets, i.e. monotonic convergence with the expected observed order of grid convergence and no scatter in the data, the method reduces to the well known Grid Convergence Index. Examples of application of the procedure are included. - Highlights: Estimation of the numerical uncertainty of any integral or local flow quantity. Least squares fits to power series expansions to handle noisy data. Excellent results obtained for manufactured solutions. Consistent results obtained for practical CFD calculations. Reduces to the well known Grid Convergence Index for well-behaved data sets.

  7. Experimental and numerical study of mixed convection with flow reversal in coaxial double-duct heat exchangers

    SciTech Connect (OSTI)

    Mare, Thierry; Voicu, Ionut; Miriel, Jacques [Laboratoire de Genie Civil et de Genie Mecanique (LGCGM), INSA de Rennes, IUT Saint Malo, 35043 Rennes (France); Galanis, Nicolas [Faculte de genie, Universite de Sherbrooke, Sherbrooke, QC (Canada); Sow, Ousmane [Laboratoire d'Energie Appliquee, Ecole superieure Polytechnique, Dakar (Senegal)

    2008-04-15

    Velocity vectors in a vertical coaxial double-duct heat exchanger for parallel ascending flow of water under conditions of laminar mixed convection have been determined experimentally using the particle image velocimetry technique. The measured velocity distributions for large annular flow rates, resulting in an essentially isothermal environment for the stream in the inner tube, are in very good agreement with corresponding numerical predictions. For flow rates of the same order of magnitude in the inner tube and the annulus, and corresponding temperature differences of about 20 C, experimental observations show that flow reversal occurs simultaneously in both streams over large axial distances for both heating and cooling of the flow in the inner tube. (author)

  8. Indonesia-Low Carbon Development Options Study | Open Energy...

    Open Energy Info (EERE)

    Indonesia-Low Carbon Development Options Study Jump to: navigation, search Name Indonesia-ESMAP Low Carbon Country Studies Program AgencyCompany Organization Energy Sector...

  9. General Renewable Energy-Market Development Studies | Open Energy...

    Open Energy Info (EERE)

    Studies Jump to: navigation, search Tool Summary LAUNCH TOOL Name: General Renewable Energy-Market Development Studies AgencyCompany Organization: World Bank Sector: Energy...

  10. BENCH SCALE SALTSTONE PROCESS DEVELOPMENT MIXING STUDY

    SciTech Connect (OSTI)

    Cozzi, A.; Hansen, E.

    2011-08-03

    The Savannah River National Laboratory (SRNL) was requested to develop a bench scale test facility, using a mixer, transfer pump, and transfer line to determine the impact of conveying the grout through the transfer lines to the vault on grout properties. Bench scale testing focused on the effect the transfer line has on the rheological property of the grout as it was processed through the transfer line. Rheological and other physical properties of grout samples were obtained prior to and after pumping through a transfer line. The Bench Scale Mixing Rig (BSMR) consisted of two mixing tanks, grout feed tank, transfer pump and transfer hose. The mixing tanks were used to batch the grout which was then transferred into the grout feed tank. The contents of the feed tank were then pumped through the transfer line (hose) using a progressive cavity pump. The grout flow rate and pump discharge pressure were monitored. Four sampling stations were located along the length of the transfer line at the 5, 105 and 205 feet past the transfer pump and at 305 feet, the discharge of the hose. Scaling between the full scale piping at Saltstone to bench scale testing at SRNL was performed by maintaining the same shear rate and total shear at the wall of the transfer line. The results of scaling down resulted in a shorter transfer line, a lower average velocity, the same transfer time and similar pressure drops. The condition of flow in the bench scale transfer line is laminar. The flow in the full scale pipe is in the transition region, but is more laminar than turbulent. The resulting plug in laminar flow in the bench scale results in a region of no-mixing. Hence mixing, or shearing, at the bench scale should be less than that observed in the full scale, where this plug is non existent due to the turbulent flow. The bench scale tests should be considered to be conservative due to the highly laminar condition of flow that exists. Two BSMR runs were performed. In both cases, wall shearing was shown to reduce the rheological properties of the grout as it was processed through the transfer line. Samples taken at the static feed tank showed that gelling impacted the rheological properties of the grout before it was fed into the pump and transfer line. A comparison of the rheological properties of samples taken at the feed tank and transfer line discharge indicated shearing of the grout was occurring in the transfer line. Bench scale testing of different mixing methods with three different salt solutions showed that method of mixing influences the rheological properties of the grouts. The paddle blade mixing method of the salt solution used for the BMSR testing provided comparable rheological properties of the grout prepared in the BMSR after 14 minutes of processing, B3. The paddle blade mixing method can be used to represent BMSR results and mixing time can be adjusted to represent larger scale mixing.

  11. Numerical and experimental study of atomic transport and Balmer line intensity in Linac4 negative ion source

    SciTech Connect (OSTI)

    Shibata, T. Nishida, K.; Hatayama, A.; Mattei, S.; Lettry, J.

    2015-04-08

    Time structure of Balmer H{sub ?} line intensity in Linac4 RF plasma has been analyzed by the combined simulation model of atomic transport and Collisional-Radiative models. As a preliminary result, time variation of the line intensity in the ignition phase of RF plasma is calculated and compared with the experimental results by photometry. For the comparison, spatial distribution of the local H{sub ?} photon emission rate at each time is calculated from the numerical model. The contribution of the local photon emission rates to the observed line intensity via optical viewing port is also investigated by application of the mock-up of the optical viewing port and the known light source. It has been clarified from the analyses that the higher and the lower peaks of the H{sub ?} line intensity observed during 1 RF cycle is mainly due to the different spatial distributions in the electron energy distribution function and the resultant local photon emission rate. These results support previous suggestion that the existence of the capacitive electric field in axial direction leads to the higher/lower peaks of the line intensity.

  12. Spin filtering in a double quantum dot device: Numerical renormalization group study of the internal structure of the Kondo state

    SciTech Connect (OSTI)

    Vernek, E.; Bsser, C. A.; Anda, E. V.; Feiguin, A. E.; Martins, G. B.

    2014-03-31

    A double quantum dot device, connected to two channels that only interact through interdot Coulomb repulsion, is analyzed using the numerical renormalization group technique. Using a two-impurity Anderson model, and realistic parameter values [S. Amasha, A. J. Keller, I. G. Rau, A. Carmi, J. A. Katine, H. Shtrikman, Y. Oreg, and D. Goldhaber-Gordon, Phys. Rev. Lett. 110, 046604 (2013)], it is shown that, by applying a moderate magnetic field and independently adjusting the gate potential of each quantum dot at half-filling, a spin-orbital SU(2) Kondo state can be achieved where the Kondo resonance originates from spatially separated parts of the device. Our results clearly link this spatial separation effect to currents with opposing spin polarizations in each channel, i.e., the device acts as a spin filter. In addition, an experimental probe of this polarization effect is suggested, pointing to the exciting possibility of experimentally probing the internal structure of an SU(2) Kondo state.

  13. Numerical Study of the Formation, Ion Spin-up and Nonlinear Stability Properties of Field-reversed Configurations

    SciTech Connect (OSTI)

    E.V. Belova; R.C. Davidson; H. Ji; M. Yamada; C.D. Cothran; M.R. Brown; M.J. Schaffer

    2004-11-12

    Results of three-dimensional numerical simulations of field-reversed configurations (FRCs) are presented. Emphasis of this work is on the nonlinear evolution of magnetohydrodynamic (MHD) instabilities in kinetic FRCs and the new FRC formation method by the counter-helicity spheromak merging. Kinetic simulations show nonlinear saturation of the n = 1 tilt mode, where n is the toroidal mode number. The n = 2 and n = 3 rotational modes are observed to grow during the nonlinear phase of the tilt instability due to the ion spin-up in the toroidal direction. The ion toroidal spin-up is shown to be related to the resistive decay of the internal flux, and the resulting loss of particle confinement. Three-dimensional MHD simulations of counter-helicity spheromak merging and FRC formation show good agreement with results from the SSX-FRC experiment. Simulations show formation of an FRC in about 30 Alfven times for typical experimental parameters. The growth rate of the n = 1 tilt mode is shown to be significantly reduced compared to the MHD growth rate due to the large plasma viscosity and field-line-tying effects.

  14. A Numerical Comparison

    Office of Scientific and Technical Information (OSTI)

    Numerical Comparison of Rule Ensemble Methods and Support Vector Machines Juan Meza ∗ Mark Woods † December 18, 2009 Abstract Machine or statistical learning is a growing field that encompasses many scientific problems including estimating parameters from data, identifying risk factors in health studies, image recognition, and finding clusters within datasets, to name just a few examples. Statistical learning can be described as "learning from data", with the goal of making a

  15. Innovative Study Helps Offshore Wind Developers Protect Wildlife |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Study Helps Offshore Wind Developers Protect Wildlife Innovative Study Helps Offshore Wind Developers Protect Wildlife October 27, 2015 - 9:33am Addthis Innovative Study Helps Offshore Wind Developers Protect Wildlife Jocelyn Brown-Saracino Jocelyn Brown-Saracino Environmental Research Manager, Wind and Water Power Technologies Office Thanks to a first-of-its-kind in-depth study of wildlife distribution and movements, the nation's Eastern Seaboard is better prepared than

  16. Case Studies in Sustainable Development in the Coal Industry...

    Open Energy Info (EERE)

    performance. The diversity of the case studies illustrates the complex and challenging nature of sustainable development. Most relate to the top priority identified in the 2002...

  17. Enabling Smart Grid Cosimulation Studies: Rapid Design and Development...

    Office of Scientific and Technical Information (OSTI)

    Enabling Smart Grid Cosimulation Studies: Rapid Design and Development of the Technologies and Controls Citation Details In-Document Search Title: Enabling Smart Grid Cosimulation ...

  18. DOE Zero Energy Ready Home Case Study: Weiss Building & Development...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    LLC., Custom Home, Downers Grove, IL DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC., Custom Home, Downers Grove, IL Case study of a DOE Zero Energy Ready ...

  19. DOE Zero Energy Ready Home Case Study: Brookside Development...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    DOE Zero Energy Ready Home Case Study: Brookside Development, Derby, CT Case study of a DOE Zero Energy Ready home in Derby, CT, that achieves a HERS score of 45 without PV or HERS ...

  20. Two-dimensional numerical study of two counter-propagating helium plasma jets in air at atmospheric pressure

    SciTech Connect (OSTI)

    Yan, Wen; Sang, Chaofeng; Wang, Dezhen; Liu, Fucheng

    2014-06-15

    In this paper, a computational study of two counter-propagating helium plasma jets in ambient air is presented. A two-dimensional fluid model is applied to investigate the physical processes of the two plasma jets interaction (PJI) driven by equal and unequal voltages, respectively. In all studied cases, the PJI results in a decrease of both plasma bullets propagation velocity. When the two plasma jets are driven by equal voltages, they never merge but rather approach each other around the middle of the gas gap at a minimum approach distance, and the minimal distance decreases with the increase of both the applied voltages and initial electron density, but increases with the increase of the relative permittivity. When the two plasma jets are driven by unequal voltages, we observe the two plasma jets will merge at the position away from the middle of the gas gap. The effect of applied voltage difference on the PJI is also studied.

  1. TWO-DIMENSIONAL NUMERICAL STUDY FOR RAYLEIGH-TAYLOR AND RICHTMYER-MESHKOV INSTABILITIES IN RELATIVISTIC JETS

    SciTech Connect (OSTI)

    Matsumoto, Jin; Masada, Youhei

    2013-07-20

    We study the stability of a non-rotating single-component jet using two-dimensional special relativistic hydrodynamic simulations. By assuming translational invariance along the jet axis, we exclude the destabilization effect by Kelvin-Helmholtz mode. The nonlinear evolution of the transverse structure of the jet with a normal jet velocity is highlighted. An intriguing finding in our study is that Rayleigh-Taylor and Richtmyer-Meshkov type instabilities can destroy cylindrical jet configuration as a result of spontaneously induced radial oscillating motion. This is powered by in situ energy conversion between the thermal and bulk kinetic energies. The effective inertia ratio of the jet to the surrounding medium {eta} determines a threshold for the onset of instabilities. The condition {eta} < 1 should be satisfied for the transverse structure of the jet being persisted.

  2. Stephanie von Numers | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Stephanie von Numers About Us Stephanie von Numers - Communications and Web Coordinator, Education & Workforce Development Stephanie von Numers joined the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy in November 2013. She supports the Education & Workforce Development team's printed and online resource development, social media activity, website maintenance and analytics, and outreach events to promote nation-wide energy literacy and career planning in the

  3. Stress-dependent permeability of fractured rock masses: A numerical...

    Office of Scientific and Technical Information (OSTI)

    permeability of fractured rock masses: A numerical study Citation Details In-Document Search Title: Stress-dependent permeability of fractured rock masses: A numerical study We ...

  4. Pueblo of Zia Renewable Energy Development Feasibility Study

    Energy Savers [EERE]

    Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA 2013 PROGRAM REVIEW Pueblo of Zia Renewable Energy Development Feasibility Study U.S. ...

  5. Pueblo of Zia - Renewable Energy Development Feasibility Study

    Energy Savers [EERE]

    2012 PROGRAM REVIEW Pueblo of Zia Renewable Energy Development Feasibility Study U.S. Department of Energy - Award No: DE-EE0005628 November 15, 2012 Operated by Los Alamos ...

  6. RAND Releases Workforce Development Studies Prepared for Energy Department

    Broader source: Energy.gov [DOE]

    The RAND Corporation released two energy-sector workforce development studies conducted on behalf of NETL: one on West Virginia and one on southwestern Pennsylvania. Their recommendations support DOE's strategic objectives, to increase energy productivity and ensure safe and responsible development of domestic energy resources.

  7. A Numerical Sensitivity Study of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    These clouds significaly impact the atmospheric radiative budget, with reductions in ... of 60-80% and are often made up of sulfates (Zhou et al., 2001; Bigg and Leck, 2001). ...

  8. Enabling Smart Grid Cosimulation Studies: Rapid Design and Development of

    Office of Scientific and Technical Information (OSTI)

    the Technologies and Controls (Journal Article) | SciTech Connect Enabling Smart Grid Cosimulation Studies: Rapid Design and Development of the Technologies and Controls Citation Details In-Document Search Title: Enabling Smart Grid Cosimulation Studies: Rapid Design and Development of the Technologies and Controls The 21st century electric power grid is transforming with an unprecedented increase in demand and increase in new technologies. In the United States Energy Independence and

  9. Numerical Study Of Melted Particles Crush Metallic Substrates And The Interaction Between Particles And A Plasma Beam In The Thermal Projection Process

    SciTech Connect (OSTI)

    Kriba, Ilhem; Djebaili, A.

    2008-09-23

    Plasma spray processes have been widely used to produce high performance coatings of a wide range of Materials (metallic, non-metallic, ceramics), offering protection from, eg. wear, extreme temperature, chemical attack and environmental corrosion. To obtain good quality coatings, spray parameters must be carefully selected. Due to the large variety in process parameters, it is difficult to optimize the process for each specific coating and substrate combinations. Furthermore modelling the spray process allows a better understanding of the process sequences during thermal spraying. Good agreement of the virtual spraying process with the real coating formation is achieved by modelling the particular process steps. The simulation of coating formation to estimate the process parameters is an important tool to develop new coating structures with defined properties. In this work, the process of plasma sprayed coating has been analyzed by numerical simulation. Commercial code is used to predict the plasma jet characteristics, plasma--particle interaction, and coating formation. Using this model we can obtain coating microstructure and characteristics which form a foundation for further improvement of an advanced ceramic coating build up model.

  10. Experimental and numerical study of the accuracy of flame-speed measurements for methane/air combustion in a slot burner

    SciTech Connect (OSTI)

    Selle, L.; Ferret, B. [Universite de Toulouse, INPT, UPS, IMFT, Institut de Mecanique des Fluides de Toulouse (France); CNRS, IMFT, Toulouse (France); Poinsot, T. [Universite de Toulouse, INPT, UPS, IMFT, Institut de Mecanique des Fluides de Toulouse (France); CNRS, IMFT, Toulouse (France); CERFACS, Toulouse (France)

    2011-01-15

    Measuring the velocities of premixed laminar flames with precision remains a controversial issue in the combustion community. This paper studies the accuracy of such measurements in two-dimensional slot burners and shows that while methane/air flame speeds can be measured with reasonable accuracy, the method may lack precision for other mixtures such as hydrogen/air. Curvature at the flame tip, strain on the flame sides and local quenching at the flame base can modify local flame speeds and require corrections which are studied using two-dimensional DNS. Numerical simulations also provide stretch, displacement and consumption flame speeds along the flame front. For methane/air flames, DNS show that the local stretch remains small so that the local consumption speed is very close to the unstretched premixed flame speed. The only correction needed to correctly predict flame speeds in this case is due to the finite aspect ratio of the slot used to inject the premixed gases which induces a flow acceleration in the measurement region (this correction can be evaluated from velocity measurement in the slot section or from an analytical solution). The method is applied to methane/air flames with and without water addition and results are compared to experimental data found in the literature. The paper then discusses the limitations of the slot-burner method to measure flame speeds for other mixtures and shows that it is not well adapted to mixtures with a Lewis number far from unity, such as hydrogen/air flames. (author)

  11. Pascua Yaqui Tribe Renewable Energy Development and Deployment Feasibility Study

    SciTech Connect (OSTI)

    Arvayo, Maria

    2014-05-30

    In 2012, PYT was awarded a grant from the Department of Energy Tribal Energy Program to conduct a Renewable Energy Development and Deployment Feasibility Study that would define the technical and economic viability of renewable energy on tribal lands. Red Mountain Energy Partners (RMEP) was hired by PYT to complete the study. Through this study, Red Mountain concluded that there are viable opportunities for solar at Tortuga Ranch, the Casino del Sol and a third site near the Justice Center on Camino de Oeste.

  12. Development Impact Assessment (DIA) Case Study. South Africa

    SciTech Connect (OSTI)

    Cox, Sadie; Nawaz, Kathleen; Sandor, Debra

    2015-05-19

    This case study reviews South Africa’s experience in considering the impacts of climate change action on development goals, focusing on the South African energy sector and development impact assessments (DIAs) that have and could be used to influence energy policy or inform the selection of energy activities. It includes a review of assessments—conducted by government ministries, technical partners, and academic institutes and non-governmental organizations (NGOs)—that consider employment, health, and water implications of possible energy sector actions, as well as multi-criteria impact assessments.

  13. Ripeness sensor development. Final report of a Phase 2 study

    SciTech Connect (OSTI)

    Stroshine, R.

    1995-08-01

    This is a final report for the Phase II study entitled ``Ripeness Sensor Development.`` The overall objective of the study was the development of a prototype device capable of testing whole fruits for sugar content. Although ripeness and sugar content are not synonymous, they are closely related. Furthermore, the consumer`s acceptance of or preference for fruits is strongly influenced by sugar content. Therefore, the device was called a ripeness sensor. The principle behind the measurement is proton magnetic resonance ({sup 1}H-MR). For several decades, chemists, pharmacists and other scientists have been using {sup 1}H-MR to investigate chemical structure and composition. More recently, the technique has been used in laboratories of the food industry for quality control. This effort represents one of the first attempts to adapt {sup 1}H-MR to use in a commercial facility. 28 refs., 36 figs., 7 tabs.

  14. Gas in developing countries: Volume 2, Country studies

    SciTech Connect (OSTI)

    Not Available

    1987-01-01

    This volume contains detailed case-studies of the history and prospects for natural gas utilization in eight developing countries: Argentina, Egypt, Malaysia, Nigeria, Pakistan, Tanzania, Thailand and Tunisia. All of these countries have been visited by members of the research team, with the exception of Pakistan. Running through all the case-histories is the importance of defining a clear market for the gas. In some cases this can prove remarkably difficult, especially when the oil price is relatively low. In other cases a market does exist, but is very limited in relation to the size of available reserves. The other theme which recurs over and over again is the importance of the relationship between the government and its agencies, and the foreign oil companies which are involved in exploration and development of gas reserves. These two issues are addressed in detail in each case study. But it is also the case that each country highlights specific aspects of the gas story.

  15. LANL researchers develop platform to study subsurface reservoir conditions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Subsurface reservoir conditions LANL researchers develop platform to study subsurface reservoir conditions This increasing demand for energy around the globe requires a better understanding of subsurface energy resources and their associated environmental issues. March 7, 2016 Shown are time lapse images of supercritical CO2 displacing water in a fracture etched into a shale micromodel. The white, blue and gray colors represent supercritical CO2, water and shale, respectively. Shown are time

  16. PUEBLO OF ZIA RENEWABLE ENERGY DEVELOPMENT FEASIBILITY STUDY

    SciTech Connect (OSTI)

    Pino, Peter M.; Lakshman, Jai; Toole, G. Loren; Witcher, James; Emerson, Michael A.; Turner, Jeremy; Sandidge, Wendy

    2014-06-30

    The Pueblo of Zia will conduct a comprehensive feasibility study for best-use application(s) for development of renewable energy resources on its tribally held TRUST lands (i.e., Trust Lands of Zia Indian Reservation). The feasibility study is essential for determining the technical and economic viability of a future renewable project(s) on Zia tribal lands, including the potential economic and environmental benefits for the Tribe. Project Objectives: The feasibility study is essential for determining the technical and economic viability of future renewable project(s) on Zia tribal lands, including the potential economic and environmental benefits for the Tribe to: 1. Provide a balanced local renewable power supply for Zia Pueblo, its members, tribal offices, schools and buildings, and businesses on tribal lands 2. Provide a firm power supply for export and commercial market distribution 3. Provide economic development for the Tribe and its members, including job training and creation, each in accordance with the goals and objectives as conveyed by the Pueblo of Zia Tribal Council, Tribal Administration, and outlined in The Pueblo of Zia Comprehensive Plan and Pueblo of Zia — Zia Enterprise Zone Master Plan. A key goal of the study is to analyze the integrated development of solar, geothermal, and wind renewable energy resources at Zia Pueblo, with added potential to combine gas-fired generation to accomplish energy firming. Geothermal offers a base load source of energy, providing power continuously for end users. Wind and solar offer intermediate and peaking sources of energy, which can be harvested throughout the day, with periods of variable but predicable output. Variability will be managed in an integrated manner, using Zia Pueblo's combined renewable resources to generate high-quality power. Tasks are intended to collect, catalog, map, and analyze existing data on Zia Pueblo's renewable energy resource base and then match resource attributes with the most suitable renewable technologies for tribal energy consumption and needs. Also, key impacts on cultural and social values of Zia Pueblo will be addressed. Selected most favorable uses and technologies will be further investigated to determine initial feasibility and market for business development for up to six sites located on tribal land. The anticipated result will be the recommended development of sites that have sufficient background study completed to warrant a business plan, detailed engineering feasibility, and acquisition of project financing. Valuable technical and economic information will accrue from this study that may be applied to scale up or down the various power technology potential on Zia Pueblo for maximum benefit and best area(s) of application, project phasing and potential for future replicability and expansion.

  17. Hawaii Solar Integration Study: Solar Modeling Developments and Study Results; Preprint

    SciTech Connect (OSTI)

    Orwig, K.; Corbus, D.; Piwko, R.; Schuerger, M.; Matsuura, M.; Roose, L.

    2012-12-01

    The Hawaii Solar Integration Study (HSIS) is a follow-up to the Oahu Wind Integration and Transmission Study completed in 2010. HSIS focuses on the impacts of higher penetrations of solar energy on the electrical grid and on other generation. HSIS goes beyond the island of Oahu and investigates Maui as well. The study examines reserve strategies, impacts on thermal unit commitment and dispatch, utilization of energy storage, renewable energy curtailment, and other aspects of grid reliability and operation. For the study, high-frequency (2-second) solar power profiles were generated using a new combined Numerical Weather Prediction model/ stochastic-kinematic cloud model approach, which represents the 'sharp-edge' effects of clouds passing over solar facilities. As part of the validation process, the solar data was evaluated using a variety of analysis techniques including wavelets, power spectral densities, ramp distributions, extreme values, and cross correlations. This paper provides an overview of the study objectives, results of the solar profile validation, and study results.

  18. HLW Glass Studies: Development of Crystal-Tolerant HLW Glasses

    SciTech Connect (OSTI)

    Matyas, Josef; Huckleberry, Adam R.; Rodriguez, Carmen P.; Lang, Jesse B.; Owen, Antionette T.; Kruger, Albert A.

    2012-04-02

    In our study, a series of lab-scale crucible tests were performed on designed glasses of different compositions to further investigate and simulate the effect of Cr, Ni, Fe, Al, Li, and RuO2 on the accumulation rate of spinel crystals in the glass discharge riser of the HLW melter. The experimental data were used to expand the compositional region covered by an empirical model developed previously (Maty et al. 2010b), improving its predictive performance. We also investigated the mechanism for agglomeration of particles and impact of agglomerates on accumulation rate. In addition, the TL was measured as a function of temperature and composition.

  19. Brazilian rain forest security - environment - development. Study project report

    SciTech Connect (OSTI)

    Arruda, P.A.

    1993-03-25

    The Amazon region has been intensely discussed in the recent years. Most of these discussions have been highly influenced by interests groups. To understand the Amazon area we need to specify what the Amazon is, to describe the forest, to evaluate its mineral and biological resources, and to study the people living in the region. A security analysis reveals that there are no main threats to Brazilian Amazon. Nevertheless, narco guerrillas, acting in neighboring countries, can cross the borders and challenge regional authorities. First World interests may disturb Brazilian policies to the region. To face these threats, Brazilian armed forces maintain a well trained military sharing with other native people the security and the routes towards progress. Brazilian government is also implementing some programs to achieve a well balanced development. The new concepts of sustainable development are applied to keep the region's natural resources available for future generations. Among these programs this paper addresses the ecological economic zoning, Calha Norte Program and Amazon Protection System (SIPAM/SIVAM). In synthesis it demonstrates the Brazilian commitment to integrate, develop and preserve this rich and exotic region.

  20. Process and equipment development for hot isostatic pressing treatability study

    SciTech Connect (OSTI)

    Bateman, Ken; Wahlquist, Dennis; Malewitz, Tim

    2015-03-01

    Battelle Energy Alliance (BEA), LLC, has developed processes and equipment for a pilot-scale hot isostatic pressing (HIP) treatability study to stabilize and volume reduce radioactive calcine stored at Idaho National Laboratory (INL). In 2009, the U. S. Department of Energy signed a Record of Decision with the state of Idaho selecting HIP technology as the method to treat 5,800 yd^3 (4,400 m^3) of granular zirconia and alumina calcine produced between 1953 and 1992 as a waste byproduct of spent nuclear fuel reprocessing. Since the 1990s, a variety of radioactive and hazardous waste forms have been remotely treated using HIP within INL hot cells. To execute the remote process at INL, waste is loaded into a stainless-steel or aluminum can, which is evacuated, sealed, and placed into a HIP furnace. The HIP simultaneously heats and pressurizes the waste, reducing its volume and increasing its durability. Two 1 gal cans of calcine waste currently stored in a shielded cask were identified as candidate materials for a treatability study involving the HIP process. Equipment and materials for cask-handling and calcine transfer into INL hot cells, as well as remotely operated equipment for waste can opening, particle sizing, material blending, and HIP can loading have been designed and successfully tested. These results demonstrate BEAs readiness for treatment of INL calcine.

  1. Direct Numerical Simulation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Numerical Simulation - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced

  2. Disruptive Innovation in Numerical Hydrodynamics

    SciTech Connect (OSTI)

    Waltz, Jacob I.

    2012-09-06

    We propose the research and development of a high-fidelity hydrodynamic algorithm for tetrahedral meshes that will lead to a disruptive innovation in the numerical modeling of Laboratory problems. Our proposed innovation has the potential to reduce turnaround time by orders of magnitude relative to Advanced Simulation and Computing (ASC) codes; reduce simulation setup costs by millions of dollars per year; and effectively leverage Graphics Processing Unit (GPU) and future Exascale computing hardware. If successful, this work will lead to a dramatic leap forward in the Laboratory's quest for a predictive simulation capability.

  3. Institute of Development Studies Feed | Open Energy Information

    Open Energy Info (EERE)

    International Institute for Sustainable Development (IISD) International Renewable Energy Agency (IRENA) Joint Implementation Network (JIN) Kumasi Institute of Technology and...

  4. Feasibility Study for Renewable Energy Development on Tribal Lands

    SciTech Connect (OSTI)

    John Hendrix, Project Director; Charles Weir, Project Manager; Dr. John Plodinec, Technology Advisor; Dr. Steve Murray, Economic Advisor

    2005-07-21

    Project Objective: The Mississippi Band of Choctaw Indians (MBCI) conducted a study of the feasibility of siting a renewable energy biomass-based installation on tribal lands. The purpose of the study was to determine whether such an installation can be economically sustainable, as well as consistent with the cultural, social, and economic goals of the Tribe. Scope: To achieve the goal of the feasibility study, the following tasks were carried out: (1) Resource availability assessment--The objective of this assessment was to determine the availability of both poultry litter and wood residues for use in the proposed facility. (2) Power utilization assessment--The objective of this assessment was to determine the potential market size for power produced, the existing infrastructure for delivering power to that market, and the costs and economic returns for doing so. (3) Technology review--The objective of this review was to identify one, or more, technical options for detailed economic and technical assessment. The study considered a range of feedstock and product mixtures of poultry litter; wood residues as feedstock; and electrical power and other ancillary products as outputs. Distributed power sources was also examined. Technologies ranging from gasification to systems that produce both power and value-added chemicals were considered. Technologies selected for detailed review were those that can be sized to process the amount of available feed (poultry litter, or poultry litter and wood residues), and that also appear to make economic sense in terms of the value of their inputs. The technology review leaned heavily on the experience from similar prior DOE projects, particularly those conducted by the National Renewable Energy Laboratory (NREL). NREL was involved in a consultative role, so that the project team could leverage their experience. (4) Systems Design(s)--Based on the technology review, a pre-conceptual design for an installation was developed. This included identification of unit operations and equipment, maintenance, manpower, feedstock requirements, and output (power and any other ancillary products). Energy and mass flows were identified. (5) Manpower development assessment--The objectives of this assessment was to identify training needs for the selected option(s), and determine how they can best be met. Using the manpower estimates from the pre-conceptual system design, skills and training needs were to be identified. A plan for providing the needed manpower was to be developed, and any associated costs determined. (6) Economic assessment--The objective of this assessment was to determine the economic viability and sustainability of the technology option(s) identified through the technical review option. The costs of bringing the feedstock to the proposed facility were combined with nominal operation costs and potential production distribution costs to identify total costs. Revenue from power distribution (and, possibly, from sale of ancillary products) were combined with any possible government credits or payments to identify gross revenue. Economic viability was determined by net revenue and return on investment. A business plan for the selected option was to be produced that would consider long-term sustainability of the project. (7) MBCI compatibility assessment--The objective of this assessment was to determine whether the renewable energy technology was compatible with the MBCI's cultural, social and economic values. As part of this assessment, the environmental impacts and benefits were to be determined (Environmental stewardship is an important part of the Choctaw culture.). The effects of a project on employment were projected. The compatibility of the renewable energy project with MBCI cultural and social values were determined. Most importantly, the compatibility of the renewable energy installation with the MBCIs economic development goals and directions were determined. A project team led by the Mississippi Band of Choctaw Indians (MBCI) conducted the feasibility study. The team included the Mississippi Alternative Energy Enterprise (MAEE), the Mississippi State University Food and Fiber Center, Mississippi State University Diagnostic Instrumentation and Analysis Laboratory (DIAL), and the Mississippi State University Department of Electrical and Computer Engineering. This report and its findings are based on the best available data existing during the covering period and the analysis reflects good faith estimates and assumptions of factors for a biomass-based renewable energy project for the Mississippi Band of Choctaw Indians and any conclusions or finding herein should not be extrapolated to other areas of the country.

  5. Numerical study of He/CF{sub 3}I pulsed discharge used to produce iodine atom in chemical oxygen-iodine laser

    SciTech Connect (OSTI)

    Zhang Jiao; Wang Yanhui; Wang Dezhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Duo Liping; Li Guofu [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116024 (China)

    2013-04-15

    The pulsed discharge for producing iodine atoms from the alkyl and perfluoroalky iodides (CH{sub 3}I, CF{sub 3}I, etc.) is the most efficient method for achieving the pulse operating mode of a chemical oxygen-iodine laser. In this paper, a one-dimensional fluid model is developed to study the characteristics of pulsed discharge in CF{sub 3}I-He mixture. By solving continuity equation, momentum equation, Poisson equation, Boltzmann equation, and an electric circuit equation, the temporal evolution of discharge current density and various discharge products, especially the atomic iodine, are investigated. The dependence of iodine atom density on discharge parameters is also studied. The results show that iodine atom density increases with the pulsed width and pulsed voltage amplitude. The mixture ratio of CF{sub 3}I and helium plays a more significant role in iodine atom production. For a constant voltage amplitude, there exists an optimal mixture ratio under which the maximum iodine atom concentration is achieved. The bigger the applied voltage amplitude is, the higher partial pressure of CF{sub 3}I is needed to obtain the maximum iodine atom concentration.

  6. Development Impact Assessment (DIA) Case Study: South Africa

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... Social impacts may include health (mortality and morbidity), poverty reduction, education, ... impacts and certain development impacts including GDP, employment, and povertywelfare. ...

  7. Confidence in Numerical Simulations

    SciTech Connect (OSTI)

    Hemez, Francois M.

    2015-02-23

    This PowerPoint presentation offers a high-level discussion of uncertainty, confidence and credibility in scientific Modeling and Simulation (M&S). It begins by briefly evoking M&S trends in computational physics and engineering. The first thrust of the discussion is to emphasize that the role of M&S in decision-making is either to support reasoning by similarity or to “forecast,” that is, make predictions about the future or extrapolate to settings or environments that cannot be tested experimentally. The second thrust is to explain that M&S-aided decision-making is an exercise in uncertainty management. The three broad classes of uncertainty in computational physics and engineering are variability and randomness, numerical uncertainty and model-form uncertainty. The last part of the discussion addresses how scientists “think.” This thought process parallels the scientific method where by a hypothesis is formulated, often accompanied by simplifying assumptions, then, physical experiments and numerical simulations are performed to confirm or reject the hypothesis. “Confidence” derives, not just from the levels of training and experience of analysts, but also from the rigor with which these assessments are performed, documented and peer-reviewed.

  8. DOE Zero Energy Ready Home Case Study 2013: Dwell Development...

    Energy Savers [EERE]

    ... RENEWABLE READY meets EPA Renewable Energy- Ready Home. 1 2 3 4 5 6 7 DOE ZERO ENERGY READY HOME Dwell Development 3 The home's one mini-split heat pump is almost overkill given ...

  9. Rythmos Numerical Integration Package

    Energy Science and Technology Software Center (OSTI)

    2006-09-01

    Rythmos numerically integrates transient differential equations. The differential equations can be explicit or implicit ordinary differential equations ofr formulated as fully implicit differential-algebraic equations. Methods include backward Euler, forward Euler, explicit Runge-Kutta, and implicit BDF at this time. Native support for operator split methods and strict modularity are strong design goals. Forward sensitivity computations will be included in the first release with adjoint sensitivities coming in the near future. Rythmos heavily relies on Thyra formore » linear algebra and nonlinear solver interfaces to AztecOO, Amesos, IFPack, and NOX in Tilinos. Rythmos is specially suited for stiff differential equations and thos applictions where operator split methods have a big advantage, e.g. Computational fluid dynamics, convection-diffusion equations, etc.« less

  10. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    SciTech Connect (OSTI)

    Soloiu, Valentin

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels?? combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  11. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    SciTech Connect (OSTI)

    Soloiu, Valentin

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  12. Development of Materials Analysis Tools for Studying NOx Adsorber Catalysts

    Broader source: Energy.gov (indexed) [DOE]

    A cooperative research and development agreement with Cummins Engine Company | Department of Energy 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters PDF icon 2005_deer_watkins.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: Catalyst Characterization (Agreement ID:9130) Project ID:18519 Mechanisms of Sulfur Poisoning of NOx Adsorber (LNT) Materials Morphology and Composition cycle of BaO/Al2O3 NSR Catalysts during NO2

  13. Continuation of Studies on Development of ODS Heat Exchanger Tubing

    SciTech Connect (OSTI)

    Lawrence Brown; David Workman; Bimal Kad; Gaylord Smith; Archie Robertson; Ian Wright

    2008-04-15

    The Department of Energy (DOE), National Energy Technology Center (NETL), has initiated a strategic plan for the development of advanced technologies needed to design and build fossil fuel plants with very high efficiency and environmental performance. These plants, referred to as 'Vision 21' and FutureGen programs by DOE, will produce electricity, chemicals, fuels, or a combination of these products, and possibly secondary products such as steam/heat for industrial use. MA956 is a prime candidate material being considered for a high temperature heat exchanger in the 'Vision 21' and FutureGen programs. This material is an oxide dispersion strengthened (ODS) alloy; however, there are some gaps in the data required to commit to the use of these alloys in a full-size plant. To fill the technology gaps for commercial production and use of the material for 'Advanced Power Generation Systems' this project has performed development activity to significant increase in circumferential strength of MA956 as compared to currently available material, investigated bonding technologies for bonding tube-to-tube joints through joining development, and performed tensile, creep and fire-side corrosion tests to validate the use and fabrication processes of MA956 to heat exchanger tubing applications. Development activities within this projected has demonstrated increased circumferential strength of MA956 tubes through flow form processing. Of the six fabrication technologies for bonding tube-to-tube joints, inertia friction welding (IFW) and flash butt welding (FBW) were identified as processes for joining MA956 tubes. Tensile, creep, and fire-side corrosion test data were generated for both base metal and weld joints. The data can be used for design of future systems employing MA956. Based upon the positive development activities, two test probes were designed and fabricated for field exposure testing at 1204 C ({approx}2200 F) flue gas. The probes contained tube portions with FBW and IFW welded MA956. Field testing of the probes and remaining heat exchanger design activity will be performed by Oak Ridge National Laboratory under DOE Contract DE-AC05-00OR22725.

  14. DOE Zero Energy Ready Home Case Study: Dwell Development, Reclaimed...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Seattle, WA, Systems Home DOE Zero Energy Ready Home: Montlake Modern - Seattle, Washington DOE Zero Energy Ready Home Case Study: Palo Duro Homes, Via del Cielo, Santa Fe, NM

  15. DOE Zero Energy Ready Home Case Study: Dwell Development, Seattle...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Case study of a DOE Zero Energy Ready Home in Seattle, WA, that scored HERS 34 without PV. This 2,000-square-foot system home has R-45 double-stud walls, an unvented flat roof with ...

  16. Renewable Energy Development on Fort Mojave Reservation Feasiblity Study

    SciTech Connect (OSTI)

    Russell Gum, ERCC analytics LLC

    2008-03-17

    The Ft. Mojave tribe, whose reservation is located along the Colorado River in the states of Arizona, California, and Nevada near the point where all three states meet, has a need for increased energy supplies. This need is a direct result of the aggressive and successful economic development projects undertaken by the tribe in the last decade. While it is possible to contract for additional energy supplies from fossil fuel sources it was the desire of the tribal power company, AHA MACAV Power Service (AMPS) to investigate the feasibility and desirability of producing power from renewable sources as an alternative to increased purchase of fossil fuel generated power and as a possible enterprise to export green power. Renewable energy generated on the reservation would serve to reduce the energy dependence of the tribal enterprises on off reservation sources of energy and if produced in excess of reservation needs, add a new enterprise to the current mix of economic activities on the reservation. Renewable energy development would also demonstrate the tribe’s support for improving environmental quality, sustainability, and energy independence both on the reservation and for the larger community.

  17. Process development studies of two-stage liquefaction at Wilsonville

    SciTech Connect (OSTI)

    Lamb, C.W.; Nalitham, R.V.; Johnson, T.W.

    1986-09-01

    The Advanced Coal Liquefaction R and D Facility at Wilsonville, Alabama, has been in operation for over 12 years. It is the largest direct coal liquefaction pilot plant still in operation in the United States. Process investigations have evolved from the original study of the Solvent Refined Coal Process for making a clean solid fuel to the recent investigation of two-stage liquefaction processes for making clean distillate fuels. This paper presents results from the current study of various processing schemes designed to reduce the cost of fuels produced by two-stage liquefaction plants.

  18. DOE ZERH Case Study: Dwell Development, Reclaimed Modern, Seattle, WA

    SciTech Connect (OSTI)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the cold climate that got a HERS 30 without PV, with 2x8 24” on center walls with blown fiberglass and 4” polysio rigid foam; basement with 2” XPS interior, 4” under slab, 4” exterior of foundation wall; vented attic with R-100 blown cellulose; wo air-to-air heat pumps SEER 14.1; HSPF 9.6; heat pump water heater.

  19. Economic Development Benefits of the Mars Hill Wind Farm, Wind Powering America Rural Economic Development, Case Study (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2009-06-01

    This case study summarizes the economic development benefits of the Mars Hill Wind Farm to the community of Mars Hill, Maine. The Mars Hill Wind Farm is New England's first utility-scale wind farm.

  20. Direct numerical simulation of turbulent reacting flows

    SciTech Connect (OSTI)

    Chen, J.H.

    1993-12-01

    The development of turbulent combustion models that reflect some of the most important characteristics of turbulent reacting flows requires knowledge about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between the turbulence and the chemistry is so strong in certain regimes that is is very difficult to isolate the role played by one individual phenomenon. Direct numerical simulation (DNS) is an extremely useful tool to study in detail the turbulence-chemistry interactions in certain well defined regimes. Globally, non-premixed flames are controlled by two limiting cases: the fast chemistry limit, where the turbulent fluctuations. In between these two limits, finite-rate chemical effects are important and the turbulence interacts strongly with the chemical processes. This regime is important because industrial burners operate in regimes in which, locally the flame undergoes extinction, or is at least in some nonequilibrium condition. Furthermore, these nonequilibrium conditions strongly influence the production of pollutants. To quantify the finite-rate chemistry effect, direct numerical simulations are performed to study the interaction between an initially laminar non-premixed flame and a three-dimensional field of homogeneous isotropic decaying turbulence. Emphasis is placed on the dynamics of extinction and on transient effects on the fine scale mixing process. Differential molecular diffusion among species is also examined with this approach, both for nonreacting and reacting situations. To address the problem of large-scale mixing and to examine the effects of mean shear, efforts are underway to perform large eddy simulations of round three-dimensional jets.

  1. STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER FACILITIE STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER...

  2. X-Ray Tools for Battery Development and Testing: Case Studies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    X-Ray Tools for Battery Development and Testing: Case Studies Case studies of the use of X-ray techniques for battery development and testing at the Advanced Photon Source PDF icon...

  3. STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED...

    Office of Environmental Management (EM)

    STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER FACILITIE STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER ...

  4. Improving the homogeneity of alternating current-drive atmospheric pressure dielectric barrier discharges in helium with an additional low-amplitude radio frequency power source: A numerical study

    SciTech Connect (OSTI)

    Wang Qi [Dalian Institute of Semiconductor Technology, School of Electronics Science and Technology, Dalian University of Technology, Dalian 116023 (China); Sun Jizhong; Zhang Jianhong; Wang Dezhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); Liu Liying [Department of Electrical Engineering, Shenyang Institute of Engineering, Shenyang 110136 (China)

    2013-04-15

    It was proposed in this paper that the homogeneity of the atmospheric pressure discharge driven by an ac power source could be improved by applying an auxiliary low-amplitude rf power source. To verify the idea, a two-dimensional fluid model then was applied to study the atmospheric discharges in helium driven by ac power, low-amplitude rf power, and combined ac and low-amplitude rf power, respectively. Simulation results confirmed that an auxiliary rf power could improve the homogeneity of a discharge driven by an ac power source. It was further found that there existed a threshold voltage of the rf power source leading to the transition from inhomogeneous to homogeneous discharge. As the frequency of the rf power source increased from 2 to 22 MHz, the magnitude of the threshold voltage dropped first rapidly and then to a constant value. When the frequency was over 13.56 MHz, the magnitude of the threshold voltage was smaller than one-sixth of the ac voltage amplitude under the simulated discharge parameters.

  5. The development of optical microscopy techniques for the advancement of single-particle studies

    SciTech Connect (OSTI)

    Marchuk, Kyle

    2013-05-15

    Single particle orientation and rotational tracking (SPORT) has recently become a powerful optical microscopy tool that can expose many molecular motions. Unfortunately, there is not yet a single microscopy technique that can decipher all particle motions in all environmental conditions, thus there are limitations to current technologies. Within, the two powerful microscopy tools of total internal reflection and interferometry are advanced to determine the position, orientation, and optical properties of metallic nanoparticles in a variety of environments. Total internal reflection is an optical phenomenon that has been applied to microscopy to produce either fluorescent or scattered light. The non-invasive far-field imaging technique is coupled with a near-field illumination scheme that allows for better axial resolution than confocal microscopy and epi-fluorescence microscopy. By controlling the incident illumination angle using total internal reflection fluorescence (TIRF) microscopy, a new type of imaging probe called non-blinking quantum dots (NBQDs) were super-localized in the axial direction to sub-10-nm precision. These particles were also used to study the rotational motion of microtubules being propelled by the motor protein kinesin across the substrate surface. The same instrument was modified to function under total internal reflection scattering (TIRS) microscopy to study metallic anisotropic nanoparticles and their dynamic interactions with synthetic lipid bilayers. Utilizing two illumination lasers with opposite polarization directions at wavelengths corresponding to the short and long axis surface plasmon resonance (SPR) of the nanoparticles, both the in-plane and out-of-plane movements of many particles could be tracked simultaneously. When combined with Gaussian point spread function (PSF) fitting for particle super-localization, the binding status and rotational movement could be resolved without degeneracy. TIRS microscopy was also used to find the 3D orientation of stationary metallic anisotropic nanoparticles utilizing only long-axis SPR enhancement. The polarization direction of the illuminating light was rotated causing the relative intensity of p-polarized and s-polarized light within the evanescent field to change. The interaction of the evanescent field with the particles is dependent on the orientation of the particle producing an intensity curve. This curve and the in-plane angle can be compared with simulations to accurately determine the 3D orientation. Differential interference contrast (DIC) microscopy is another non-invasive far-field technique based upon interferometry that does not rely on staining or other contrast enhancing techniques. In addition, high numerical aperture condensers and objectives can be used to give a very narrow depth of field allowing for the optical tomography of samples, which makes it an ideal candidate to study biological systems. DIC microscopy has also proven itself in determining the orientation of gold nanorods in both engineered environments and within cells. Many types of nanoparticles and nanostructures have been synthesized using lithographic techniques on silicon wafer substrates. Traditionally, reflective mode DIC microscopes have been developed and applied to the topographical study of reflective substrates and the imaging of chips on silicon wafers. Herein, a laser-illuminated reflected-mode DIC was developed for studying nanoparticles on reflective surfaces.

  6. Numerical prediction of window condensation potential

    SciTech Connect (OSTI)

    McGowan, A.G.

    1995-08-01

    Although a substantial amount of effort has been expended to develop numerical methods for determining windows U-factors (EE 1983; Goss and Curcija 1994; Standaert 1985; CSA 1993a; NFRC 1991), there has been little work to data on using numerical methods to predict condensation potential. It is perhaps of direct interest to most ASHRAE members to determine heat loss and solar gains through windows as a precursor to sizing heating and cooling equipment, but condensation has long been recognized as an extremely important issue for consumers (and, consequently, for window manufacturers). Moreover, building scientists recognize the link between condensation and increased energy consumption (due to latent loads), reduced occupant comfort and indoor air quality (from the presence of bacteria and mold), and structural damage (where accumulated condensation is absorbed by the building material, thus reducing their structural stability). The National Fenestration Rating Council (NFRC) is developing a rating method for condensation potential in fenestration products as part of its mandate from the US Department of Energy (DOE). A rating method would benefit from the use of simulation as a supplement to physical condensation resistance testing to reduce the cost and time required for implementation and increase the flexibility of the rating method. This paper outlines one of the necessary components in the application of numerical methods for evaluating condensation in fenestration products. The theoretical approach and its practical application are discussed, as well as some comparisons between numerical prediction and physical test results for a sample of products.

  7. Mechanical diode: Comparing numerical and experimental characterizations

    SciTech Connect (OSTI)

    Sagartz, M.J.; Segalman, D.; Simmermacher, T.

    1998-02-01

    In this introductory work, joint compliance is studied in both a numerical and experimental setting. A simple bolted interface is used as the test article and compliance is measured for the joint in both compression and in tension. This simple interface is shown to exhibit a strong non-linearity near the transition from compression to tension (or vice-versa). Modeling issues pertaining to numerically solving for the compliance are addressed. It is shown that the model predictions, in spite of convergence being very sensitive to numerical artifacts of the interface model, are in good agreement with experimentally measured strains and joint compliances. The joint behavior is a mechanical analogy to a diode, i.e., in compression, the joint is very stiff, acting almost as a rigid link, while in tension the joint is relatively soft, acting as a spring.

  8. Numerical simulations of strong incompressible magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Mason, J.; Cattaneo, F.; Perez, J. C.; Boldyrev, S.

    2012-05-15

    Magnetised plasma turbulence pervades the universe and is likely to play an important role in a variety of astrophysical settings. Magnetohydrodynamics (MHD) provides the simplest theoretical framework in which phenomenological models for the turbulent dynamics can be built. Numerical simulations of MHD turbulence are widely used to guide and test the theoretical predictions; however, simulating MHD turbulence and accurately measuring its scaling properties is far from straightforward. Computational power limits the calculations to moderate Reynolds numbers and often simplifying assumptions are made in order that a wider range of scales can be accessed. After describing the theoretical predictions and the numerical approaches that are often employed in studying strong incompressible MHD turbulence, we present the findings of a series of high-resolution direct numerical simulations. We discuss the effects that insufficiencies in the computational approach can have on the solution and its physical interpretation.

  9. Solid state NMR method development and studies of biological and biomimetic nanocomposites

    SciTech Connect (OSTI)

    Hu, Yanyan

    2011-02-07

    This thesis describes application and development of advanced solid-state nuclear magnetic resonance techniques for complex materials, in particular organic-inorganic nanocomposites and thermoelectric tellurides. The apatite-collagen interface, essential for understanding the biomineralization process in bone and engineering the interface for controlled bio-mimetic synthesis and optimized mechanical properties, is buried within the nanocomposite of bone. We used multinuclear solid-state NMR to study the composition and structure of the interface. Citrate has been identified as the main organic molecule strongly bound to the apatite surface with a density of 1/(2 nm){sup 2}, covering 1/6 of the total surface area in bovine bone. Citrate provides more carboxylate groups, one of the key functional groups found to affect apatite nucleation and growth, than all the non-collagenous proteins all together in bone; thus we propose that citrate stabilizes apatite crystals at a very small thickness of {approx}3 nm (4 unit cells) to increase bone fracture tolerance. The hypothesis has been confirmed in vitro by adding citrate in the bio-mimetic synthesis of polymerhydroxyapatite nanocomposites. The results have shown that the size of hydroxyapatite nanocrystals decreases as increasing citrate concentration. With citrate concentrations comparable to that in body fluids, similar-sized nanocrystals as in bone have been produced. Besides the dimensions of the apatite crystals, the composition of bone also affects its biofunctional and macroscopic mechanical properties; therefore, our team also extended its effort to enhance the inorganic portion in our bio-mimetic synthesis from originally 15 wt% to current 50 wt% compared to 65 wt% in bovine bone, by using Lysine-Leucine hydroxyapatite nucleating diblock co-polypeptide, which forms a gel at very low concentration. In this thesis, various advanced solid state NMR techniques have been employed to characterize nanocomposites. Meanwhile, we have developed new methods to achieve broadband high resolution NMR and improve the accuracy of inter-nuclear distance measurements involving quadrupolar spins. Broadband high resolution NMR of spin-1/2 nuclei has been accomplished by the adaptation of the magic angle turning (MAT) method to fast magic angle spinning, termed fast MAT, by solving technical problems such as off resonance effects. Fast MAT separates chemical shift anisotropy and isotropic chemical shifts over a spectral range of {approx}1.8 {gamma}B{sub 1} without significant distortions. Fast MAT {sup 125}Te NMR has been applied to study technologically important telluride materials with spectra spreading up to 190 kHz. The signal-to-noise ratio of the spectra is significantly improved by using echo-matched Gaussian filtering in offline data processing. The accuracy of the measured distances between spin-1/2 and quadrupolar nuclei with methods such as SPIDER and REAPDOR has been improved by compensating for the fast longitudinal quadrupolar relaxation on the sub-millisecond with a modified S{sub 0} pulse sequence. Also, the T1Q effect on the spin coherence and its spinning speed dependency has been explored and documented with analytical and numerical simulations as well as experimental measurements.

  10. DOE Zero Energy Ready Home Case Study: Brookside Development, Derby, CT |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Brookside Development, Derby, CT DOE Zero Energy Ready Home Case Study: Brookside Development, Derby, CT DOE Zero Energy Ready Home Case Study: Brookside Development, Derby, CT Case study of a DOE Zero Energy Ready home in Derby, CT, that achieves a HERS score of 45 without PV or HERS 26 with PV. The production home is one of a development of 7 two-story, 4,000+-ft2 certified homes that have 2x4 walls filled with 1.5 in. closed-cell spray foam, 2-in. fiberglass batt,

  11. Numerical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Data Series: No. of Residential Consumers No. of Residential Sales Consumers No. of Res. Transported Consumers No. of Commercial Consumers No. of Commercial Sales Consumers No. of Commercial Transported Consumers Avg. Consumption per Comm. Consumer No. of Industrial Consumers No. of Industrial Sales Consumers No. of Industrial Transported Consumers Avg. Consumption per Indust. Consumer Period: Annual Download Series History Download Series History Definitions, Sources & Notes Definitions,

  12. Developing a Millifluidic Platform for the Synthesis of Ultrasmall Nanoclusters: Ultrasmall Copper Nanoclusters as a Case Study

    SciTech Connect (OSTI)

    Biswas, Sanchita [Louisiana State Univ., Baton Rouge, LA (United States). Center for Advanced Microstructures and Devices and Center for Atomic-level Catalysts Design; Miller, Jeffrey T. [Argonne National Lab. (ANL), Argonne, IL (United States); Li, Yuehao [Louisiana State Univ., Baton Rouge, LA (United States). Cain Dept. of Chemical Engineering; Nandakumar, Krishnaswamy [Louisiana State Univ., Baton Rouge, LA (United States). Cain Dept. of Chemical Engineering; Kumar, Challa S.S.R. [Louisiana State Univ., Baton Rouge, LA (United States). Center for Advanced Microstructures and Devices and Center for Atomic-level Catalysts Design

    2012-02-02

    The future of lab-on-a-chip devices for the synthesis of nanomaterials hinges on the successful development of high-throughput methods with better control over their size. While significant effort in this direction mainly focuses on developing difficult to fabricate complex microfluidic reactors, scant attention has been paid to the easy to fabricate and simple millifluidic systems that could provide the required control as well as high throughput. By utilizing numerical simulation of fluids within the millifluidic space at different flow rates, the results presented here show velocity profiles and residence time distributions similar to the case of microfluidics. By significantly reducing the residence time and residence time distribution, a continuous flow synthesis of ultrasmall copper nanoclusters (UCNCs) with exceptional colloidal stability is achieved. In-situ synchrotron-radiation-based X-ray absorption spectroscopy (XAS) reveal that the as-prepared clusters are about 1 nm, which is further supported by transmission electron microscopy and UVvis spectroscopy studies. The clusters reported here are the smallest ever produced using a lab-on-a-chip platform. When supported on silica, they are found to efficiently catalyze CH oxidation reactions, hitherto unknown to be catalyzed by Cu. This work suggests that a millifluidic platform can be an inexpensive, versatile, easy-to-use, and powerful tool for nanoparticle synthesis in general, and more specifically for ultrasmall nanoclusters (UNCs).

  13. Self-similar radiation from numerical Rosenau-Hyman compactons

    SciTech Connect (OSTI)

    Rus, Francisco Villatoro, Francisco R.

    2007-11-10

    The numerical simulation of compactons, solitary waves with compact support, is characterized by the presence of spurious phenomena, as numerically induced radiation, which is illustrated here using four numerical methods applied to the Rosenau-Hyman K(p, p) equation. Both forward and backward radiations are emitted from the compacton presenting a self-similar shape which has been illustrated graphically by the proper scaling. A grid refinement study shows that the amplitude of the radiations decreases as the grid size does, confirming its numerical origin. The front velocity and the amplitude of both radiations have been studied as a function of both the compacton and the numerical parameters. The amplitude of the radiations decreases exponentially in time, being characterized by a nearly constant scaling exponent. An ansatz for both the backward and forward radiations corresponding to a self-similar function characterized by the scaling exponent is suggested by the present numerical results.

  14. Numerical evaluation of effective unsaturated hydraulic properties for

    Office of Scientific and Technical Information (OSTI)

    fractured rocks (Journal Article) | SciTech Connect Journal Article: Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks Citation Details In-Document Search Title: Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks To represent a heterogeneous unsaturated fractured rock by its homogeneous equivalent, Monte Carlo simulations are used to obtain upscaled (effective) flow properties. In this study, we present a numerical

  15. DOE Zero Energy Ready Home Case Study: Dwell Development, Reclaimed Modern,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Seattle, WA | Department of Energy Dwell Development, Reclaimed Modern, Seattle, WA DOE Zero Energy Ready Home Case Study: Dwell Development, Reclaimed Modern, Seattle, WA DOE Zero Energy Ready Home Case Study: Dwell Development, Reclaimed Modern, Seattle, WA Case study of a DOE 2015 Housing Innovation Award winning custom home in the marine climate that got a HERS 55 without PV, or HERS 25 with PV, with 2x8 24" on center walls with R-27 dense-packed cellulose; R-20 rigid foam under

  16. Numerical simulations shed new light on early universe

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Numerical simulations shed new light on early universe Numerical simulations shed new light on early universe The code simulates conditions during the first few minutes of cosmological evolution to model the role of neutrinos, nuclei and other particles in shaping the early universe. April 21, 2016 Los Alamos scientists developed the BURST computer code to predict-to unprecedented precision-the amounts of light nuclei synthesized in the Big Bang. Los Alamos scientists developed the BURST

  17. Defining the Interactions of Cellobiohydrolase with Substrate through Structure Function Studies: Cooperative Research and Development Final Report, CRADA Number CRD-10-409

    SciTech Connect (OSTI)

    Beckham, G. T.; Himmel, M. E.

    2013-07-01

    NREL researchers will use their expertise and skilled resources in numerical computational modeling to generate structure-function relationships for improved cellulase variant enzymes to support the development of cellulases with improved performance in biomass conversion.

  18. Strategic Development of the Idea. LEEM-PEEM Studies of InGaN-based

    Office of Scientific and Technical Information (OSTI)

    Heterostructures (Technical Report) | SciTech Connect Technical Report: Strategic Development of the Idea. LEEM-PEEM Studies of InGaN-based Heterostructures Citation Details In-Document Search Title: Strategic Development of the Idea. LEEM-PEEM Studies of InGaN-based Heterostructures Abstract not provided. Authors: Ohta, Taisuke [1] + Show Author Affiliations Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States) Publication Date: 2015-09-01 OSTI Identifier: 1221950 Report

  19. Development of a Fast Microfluidic Mixer for Studies of Protein Folding

    Office of Scientific and Technical Information (OSTI)

    KineticsFinal Report Cover Page (Technical Report) | SciTech Connect Development of a Fast Microfluidic Mixer for Studies of Protein Folding KineticsFinal Report Cover Page Citation Details In-Document Search Title: Development of a Fast Microfluidic Mixer for Studies of Protein Folding KineticsFinal Report Cover Page We designed and fabricated mixing devices that will help us elucidate the mechanisms of protein folding through measurements of folding reaction rates. These devices can be

  20. The Development and Application of NMR Methodologies for the Study of

    Office of Scientific and Technical Information (OSTI)

    Degradation in Complex Silicones (Journal Article) | SciTech Connect Development and Application of NMR Methodologies for the Study of Degradation in Complex Silicones Citation Details In-Document Search Title: The Development and Application of NMR Methodologies for the Study of Degradation in Complex Silicones Authors: Maxwell, R S ; Lewicki, J P ; Mayer, B P ; Maiti, A ; Harley, S J Publication Date: 2013-04-19 OSTI Identifier: 1144771 Report Number(s): LLNL-JRNL-635880 DOE Contract

  1. Guide to good practices for developing and conducting case studies: DOE handbook

    SciTech Connect (OSTI)

    1998-01-01

    Learning from experience is often very costly to a facility in terms of injured personnel, damaged equipment, and wasted time. Learning from the experience gained at the facility and from industry can prevent repeating costly mistakes. This guide contains a method for learning from experience to prevent mistakes from occurring; that method is the case study. This guide describes how to develop and present case studies. This guide provides the instructional developer insight on the best kind of case study to use and includes examples of the various types of case studies.

  2. Image reconstruction of single photon emission computed tomography (SPECT) on a pebble bed reactor (PBR) using expectation maximization and exact inversion algorithms: Comparison study by means of numerical phantom

    SciTech Connect (OSTI)

    Razali, Azhani Mohd Abdullah, Jaafar

    2015-04-29

    Single Photon Emission Computed Tomography (SPECT) is a well-known imaging technique used in medical application, and it is part of medical imaging modalities that made the diagnosis and treatment of disease possible. However, SPECT technique is not only limited to the medical sector. Many works are carried out to adapt the same concept by using high-energy photon emission to diagnose process malfunctions in critical industrial systems such as in chemical reaction engineering research laboratories, as well as in oil and gas, petrochemical and petrochemical refining industries. Motivated by vast applications of SPECT technique, this work attempts to study the application of SPECT on a Pebble Bed Reactor (PBR) using numerical phantom of pebbles inside the PBR core. From the cross-sectional images obtained from SPECT, the behavior of pebbles inside the core can be analyzed for further improvement of the PBR design. As the quality of the reconstructed image is largely dependent on the algorithm used, this work aims to compare two image reconstruction algorithms for SPECT, namely the Expectation Maximization Algorithm and the Exact Inversion Formula. The results obtained from the Exact Inversion Formula showed better image contrast and sharpness, and shorter computational time compared to the Expectation Maximization Algorithm.

  3. PURPA Resource Development in the Pacific Northwest : Case Studies of Ten Electricity Generating Powerplants.

    SciTech Connect (OSTI)

    Washington State Energy Office.

    1990-07-01

    The case studies in this document describe the Public Utilities, Regulatory Policies Act (PURPA) development process for a variety of generating technologies. Developer interactions with regulatory agencies and power purchasers are described in some detail. Equipment, installation, and maintenance costs are identified; power marketing considerations are taken into account; and potential environmental impacts, with corresponding mitigation approaches and practices are summarized. The project development case studies were prepared by the energy agencies of the four Northwest states, under contract to the Bonneville Power Administration.

  4. Mathematical and Numerical Analyses of Peridynamics for Multiscale Materials Modeling

    SciTech Connect (OSTI)

    Gunzburger, Max

    2015-02-17

    We have treated the modeling, analysis, numerical analysis, and algorithmic development for nonlocal models of diffusion and mechanics. Variational formulations were developed and finite element methods were developed based on those formulations for both steady state and time dependent problems. Obstacle problems and optimization problems for the nonlocal models were also treated and connections made with fractional derivative models.

  5. Subtask 2.2 - Creating A Numerical Technique for Microseismic Data Inversion

    SciTech Connect (OSTI)

    Anastasia Dobroskok; Yevhen Holubnyak; James Sorensen

    2009-05-01

    Geomechanical and geophysical monitoring are the techniques which can complement each other and provide enhancement in the solutions of many problems of geotechnical engineering. One of the most promising geophysical techniques is passive seismic monitoring. The essence of the technique is recording the acoustic signals produced in the subsurface, either naturally or in response to human activity. The acoustic signals are produced by mechanical displacements on the contacts of structural elements (e.g., faults, boundaries of rock blocks, natural and induced fractures). The process can be modeled by modern numerical techniques developed in geomechanics. The report discusses a study that was aimed at the unification of the passive seismic monitoring and numerical modeling for the monitoring of the hydraulic fracture propagation. The approach adopted in the study consisted of numerical modeling of the seismicity accompanying hydraulic fracture propagation and defining seismic attributes and patterns characterizing the process and fracture parameters. Numerical experiments indicated that the spatial distribution of seismic events is correlated to geometrical parameters of hydrofracture. Namely, the highest density of the events is observed along fracture contour, and projection of the events to the fracture plane makes this effect most pronounced. The numerical experiments also showed that dividing the totality of the events into groups corresponding to the steps of fracture propagation allows for reconstructing the geometry of the resulting fracture more accurately than has been done in the majority of commercial applications.

  6. Numerical recipes for mold filling simulation

    SciTech Connect (OSTI)

    Kothe, D.; Juric, D.; Lam, K.; Lally, B.

    1998-07-01

    Has the ability to simulate the filling of a mold progressed to a point where an appropriate numerical recipe achieves the desired results? If results are defined to be topological robustness, computational efficiency, quantitative accuracy, and predictability, all within a computational domain that faithfully represents complex three-dimensional foundry molds, then the answer unfortunately remains no. Significant interfacial flow algorithm developments have occurred over the last decade, however, that could bring this answer closer to maybe. These developments have been both evolutionary and revolutionary, will continue to transpire for the near future. Might they become useful numerical recipes for mold filling simulations? Quite possibly. Recent progress in algorithms for interface kinematics and dynamics, linear solution methods, computer science issues such as parallelization and object-oriented programming, high resolution Navier-Stokes (NS) solution methods, and unstructured mesh techniques, must all be pursued as possible paths toward higher fidelity mold filling simulations. A detailed exposition of these algorithmic developments is beyond the scope of this paper, hence the authors choose to focus here exclusively on algorithms for interface kinematics. These interface tracking algorithms are designed to model the movement of interfaces relative to a reference frame such as a fixed mesh. Current interface tracking algorithm choices are numerous, so is any one best suited for mold filling simulation? Although a clear winner is not (yet) apparent, pros and cons are given in the following brief, critical review. Highlighted are those outstanding interface tracking algorithm issues the authors feel can hamper the reliable modeling of today`s foundry mold filling processes.

  7. STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AND POWER FACILITIE | Department of Energy STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER FACILITIE STUDY OF THE EFFECT OF PRIVATE WIRE LAWS ON DEVELOPMENT OF COMBINED HEAT AND POWER FACILITIE Section 1308 of the Energy Independence and Security Act of 2007 ("EISA 2007") directed the Secretary of Energy, in consultation with the States, to undertake a study of the laws affecting the siting of privately-owned distribution wires on or across public

  8. RELAP-7 Numerical Stabilization: Entropy Viscosity Method

    SciTech Connect (OSTI)

    R. A. Berry; M. O. Delchini; J. Ragusa

    2014-06-01

    The RELAP-7 code is the next generation nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). The code is based on the INL's modern scientific software development framework, MOOSE (Multi-Physics Object Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5's capability and extends the analysis capability for all reactor system simulation scenarios. RELAP-7 utilizes a single phase and a novel seven-equation two-phase flow models as described in the RELAP-7 Theory Manual (INL/EXT-14-31366). The basic equation systems are hyperbolic, which generally require some type of stabilization (or artificial viscosity) to capture nonlinear discontinuities and to suppress advection-caused oscillations. This report documents one of the available options for this stabilization in RELAP-7 -- a new and novel approach known as the entropy viscosity method. Because the code is an ongoing development effort in which the physical sub models, numerics, and coding are evolving, so too must the specific details of the entropy viscosity stabilization method. Here the fundamentals of the method in their current state are presented.

  9. Numerical solution of the time dependent neutron transport equation by the method of the characteristics

    SciTech Connect (OSTI)

    Talamo, Alberto

    2013-05-01

    This study presents three numerical algorithms to solve the time dependent neutron transport equation by the method of the characteristics. The algorithms have been developed taking into account delayed neutrons and they have been implemented into the novel MCART code, which solves the neutron transport equation for two-dimensional geometry and an arbitrary number of energy groups. The MCART code uses regular mesh for the representation of the spatial domain, it models up-scattering, and takes advantage of OPENMP and OPENGL algorithms for parallel computing and plotting, respectively. The code has been benchmarked with the multiplication factor results of a Boiling Water Reactor, with the analytical results for a prompt jump transient in an infinite medium, and with PARTISN and TDTORT results for cross section and source transients. The numerical simulations have shown that only two numerical algorithms are stable for small time steps.

  10. Spin filtering in a double quantum dot device: Numerical renormalization

    Office of Scientific and Technical Information (OSTI)

    group study of the internal structure of the Kondo state (Journal Article) | SciTech Connect Spin filtering in a double quantum dot device: Numerical renormalization group study of the internal structure of the Kondo state Citation Details In-Document Search Title: Spin filtering in a double quantum dot device: Numerical renormalization group study of the internal structure of the Kondo state A double quantum dot device, connected to two channels that only interact through interdot Coulomb

  11. Development characteristics of polymethyl methacrylate in alcohol/water mixtures. A lithography and Raman spectroscopy study

    SciTech Connect (OSTI)

    Ocola, Leonidas E.; Costales, Maya; Gosztola, David J.

    2015-12-10

    Poly methyl methacrylate (PMMA) is the most widely used resist in electron beam lithography. This paper reports on a lithography and Raman spectroscopy study of development characteristics of PMMA in methanol, ethanol and isopropanol mixtures with water as developers. We have found that ethanol/water mixtures at a 4:1 volume ratio are an excellent, high resolution, non-toxic, developer for exposed PMMA. We also have found that the proper methodology to use so that contrast data can be compared to techniques used in polymer science is not to rinse the developed resist but to immediately dry with nitrogen. Our results show how powerful simple lithographic techniques can be used to study ternary polymer solvent solutions when compared to other techniques used in the literature. Raman data shows that there both tightly bonded –OH groups and non-hydrogen bonded –OH groups play a role in the development of PMMA. Tightly hydrogen bonded –OH groups show pure Lorentzian Raman absorption only in the concentration ranges where ethanol/water and IPA/water mixtures are effective developers of PMMA. The impact of the understanding these interactions may open doors to a new developers of other electron beam resists that can reduce the toxicity of the waste stream.

  12. DOE Zero Energy Ready Home Case Study: Dwell Development, Seattle, WA,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Systems Home | Department of Energy Dwell Development, Seattle, WA, Systems Home DOE Zero Energy Ready Home Case Study: Dwell Development, Seattle, WA, Systems Home Case study of a DOE Zero Energy Ready Home in Seattle, WA, that scored HERS 34 without PV. This 2,000-square-foot system home has R-45 double-stud walls, an unvented flat roof with 2 inches of spray foam plus 18 inches blown cellulose, R-42 XPS under slab, triple-pane windows, and a ductless mini-split heat pump. PDF icon Dwell

  13. DOE Zero Energy Ready Home Case Study: StreetScape Development, LLC,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Libertyville, IL, Custom | Department of Energy StreetScape Development, LLC, Libertyville, IL, Custom DOE Zero Energy Ready Home Case Study: StreetScape Development, LLC, Libertyville, IL, Custom Case study of a DOE Zero Energy Ready Home in Libertyville, IL, that scored HERS 45 without PV. This 2,763-square-foot custom home has advanced framed walls with R-20 of open-cell spray foam, R-49 open-cell spray-foam sealed attic, an HRV, and a tankless water heater for hydro coil furnace with

  14. Development of a Fast Microfluidic Mixer for Studies of Protein Folding

    Office of Scientific and Technical Information (OSTI)

    KineticsFinal Report Cover Page (Technical Report) | SciTech Connect Technical Report: Development of a Fast Microfluidic Mixer for Studies of Protein Folding KineticsFinal Report Cover Page Citation Details In-Document Search Title: Development of a Fast Microfluidic Mixer for Studies of Protein Folding KineticsFinal Report Cover Page × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical

  15. Development of ion beam techniques for the study of special nuclear materials related problems

    SciTech Connect (OSTI)

    Maggiore, C.J.; Tesmer, J.R.; Martz, J.C.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The scientific objective of this project was to develop the ion beam techniques for the characterization of actinides and their effects on other materials. It was designed to enhance their ability to quantitatively understand the oxidation, corrosion, diffusion, stability, and radiation damage of actinides and the materials with which they are in contact. The authors developed and applied several low-energy nuclear techniques (resonant and nonresonant backscattering, nuclear reaction analysis, and particle-induced x-ray emission) to the quantitative study of the near surfaces of actinide and tritide materials, and determined the absolute accuracy and precision of ion beam measurements on these materials. They also demonstrated the use of variable-energy alpha beams for the study of accelerated aging of polymeric materials in contact with actinide materials.

  16. DOE Zero Energy Ready Home Case Study: Brookside Development, Derby, CT

    Broader source: Energy.gov [DOE]

    Case study of a DOE Zero Energy Ready home in Derby, CT, that achieves a HERS score of 45 without PV or HERS 26 with PV. The production home is one of a development of 7 two-story, 4,000+-ft2...

  17. Development of an Online Toolkit for Measuring Commercial Building Energy Efficiency Performance -- Scoping Study

    SciTech Connect (OSTI)

    Wang, Na

    2013-03-13

    This study analyzes the market needs for building performance evaluation tools. It identifies the existing gaps and provides a roadmap for the U.S. Department of Energy (DOE) to develop a toolkit with which to optimize energy performance of a commercial building over its life cycle.

  18. Leadership development study :success profile competencies and high-performing leaders at Sandia National Laboratories.

    SciTech Connect (OSTI)

    Becker, Katherine M.; Mulligan, Deborah Rae; Szenasi, Gail L.; Crowder, Stephen Vernon

    2005-04-01

    Sandia is undergoing tremendous change. Sandia's executive management recognized the need for leadership development. About ten years ago the Business, Leadership, and Management Development department in partnership with executive management developed and implemented the organizational leadership Success Profile Competencies to help address some of the changes on the horizon such as workforce losses and lack of a skill set in the area of interpersonal skills. This study addresses the need for the Business, Leadership, and Management Development department to provide statistically sound data in two areas. One is to demonstrate that the organizational 360-degree success profile assessment tool has made a difference for leaders. A second area is to demonstrate the presence of high performing leaders at the Labs. The study utilized two tools to address these two areas. Study participants were made up of individuals who have solid data on Sandia's 360-degree success profile assessment tool. The second assessment tool was comprised of those leaders who participated in the Lockheed Martin Corporation Employee Preferences Survey. Statistical data supports the connection between leader indicators and the 360-degree assessment tool. The study also indicates the presence of high performing leaders at Sandia.

  19. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect (OSTI)

    Not Available

    1991-02-02

    This report consists of Detailed Data Acquisition Sheets for Runs E-6 and E-7 for Task 2.2 of the Modification, Operation, and Support Studies of the Liquid Phase Methanol Laporte Process Development Unit. (Task 2.2: Alternate Catalyst Run E-6 and Catalyst Activity Maintenance Run E-7).

  20. 2007 Wholesale Power Rate Case Initial Proposal : Wholesale Power Rate Development Study.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    2007-11-01

    The Wholesale Power Rate Development Study (WPRDS) calculates BPA proposed rates based on information either developed in the WPRDS or supplied by the other studies that comprise the BPA rate proposal. All of these studies, and accompanying documentation, provide the details of computations and assumptions. In general, information about loads and resources is provided by the Load Resource Study (LRS), WP-07-E-BPA-01, and the LRS Documentation, WP-07-E-BPA-01A. Revenue requirements information, as well as the Planned Net Revenues for Risk (PNNR), is provided in the Revenue Requirement Study, WP-07-E-BPA-02, and its accompanying Revenue Requirement Study Documentation, WP-07-E-BPA-02A and WP-07-E-BPA-02B. The Market Price Forecast Study (MPFS), WP-07-E-BPA-03, and the MPFS Documentation, WP-07-E-BPA-03A, provide the WPRDS with information regarding seasonal and diurnal differentiation of energy rates, as well information regarding monthly market prices for Demand Rates. In addition, this study provides information for the pricing of unbundled power products. The Risk Analysis Study, WP-07-E-BPA-04, and the Risk Analysis Study Documentation, WP-07-E-BPA-04A, provide short-term balancing purchases as well as secondary energy sales and revenue. The Section 7(b)(2) Rate Test Study, WP-07-E-BPA-06, and the Section 7(b)(2) Rate Test Study Documentation, WP-07-E-BPA-06A, implement Section 7(b)(2) of the Northwest Power Act to ensure that BPA preference customers firm power rates applied to their general requirements are no higher than rates calculated using specific assumptions in the Northwest Power Act.

  1. Numerical computation of Pop plot

    SciTech Connect (OSTI)

    Menikoff, Ralph

    2015-03-23

    The Pop plot — distance-of-run to detonation versus initial shock pressure — is a key characterization of shock initiation in a heterogeneous explosive. Reactive burn models for high explosives (HE) must reproduce the experimental Pop plot to have any chance of accurately predicting shock initiation phenomena. This report describes a methodology for automating the computation of a Pop plot for a specific explosive with a given HE model. Illustrative examples of the computation are shown for PBX 9502 with three burn models (SURF, WSD and Forest Fire) utilizing the xRage code, which is the Eulerian ASC hydrocode at LANL. Comparison of the numerical and experimental Pop plot can be the basis for a validation test or as an aid in calibrating the burn rate of an HE model. Issues with calibration are discussed.

  2. Development and Applications Of Photosensitive Device Systems To Studies Of Biological And Organic Materials

    SciTech Connect (OSTI)

    Gruner, Sol

    2012-01-20

    The primary focus of the grant is the development of new x-ray detectors for biological and materials work at synchrotron sources, especially Pixel Array Detectors (PADs), and the training of students via research applications to problems in biophysics and materials science using novel x-ray methods. This Final Progress Report provides a high-level overview of the most important accomplishments. These major areas of accomplishment include: (1) Development and application of x-ray Pixel Array Detectors; (2) Development and application of methods of high pressure x-ray crystallography as applied to proteins; (3) Studies on the synthesis and structure of novel mesophase materials derived from block co-polymers.

  3. Scientist-Teacher Partnerships as Professional Development: An Action Research Study

    SciTech Connect (OSTI)

    Willcuts, Meredith H.

    2009-04-17

    SUBMITTED AS A DOCTORAL DISSERTATION IN COMPLETION OF REQUIREMENTS FOR THE DEGREE OF ED.D THROUGH WASHINGTON STATE UNIVERSITY. The overall purpose of this action research study was to explore the experiences of ten middle school science teachers involved in a three-year partnership program between scientists and teachers at a Department of Energy national laboratory, including the impact of the program on their professional development, and to improve the partnership program by developing a set of recommendations based on the study’s findings. This action research study relied on qualitative data including field notes recorded at the summer academies and data from two focus groups with teachers and scientists. Additionally, the participating teachers submitted written reflections in science notebooks, participated in open-ended telephone interviews that were transcribed verbatim, and wrote journal summaries to the Department of Energy at the end of the summer academy. The analysis of the data, collaboratively examined by the teachers, the scientists, and the science education specialist acting as co-researchers on the project, revealed five elements critical to the success of the professional development of science teachers. First, scientist-teacher partnerships are a unique contribution to the professional development of teachers of science that is not replicated in other forms of teacher training. Second, the role of the science education specialist as a bridge between the scientists and teachers is a unique and vital one, impacting all aspects of the professional development. Third, there is a paradox for classroom teachers as they view the professional development experience from two different lenses – that of learner and that of teacher. Fourth, learning for science teachers must be designed to be constructivist in nature. Fifth, the principles of the nature of science must be explicitly showcased to be seen and understood by the classroom teacher.

  4. Agua Caliente Solar Feasibility and Pre-Development Study Final Report

    SciTech Connect (OSTI)

    Carolyn T. Stewart, Managing Partner; Red Mountain Energy Partners

    2011-04-26

    Evaluation of facility- and commercial-scale solar energy projects on the Agua Caliente Band of Cahuilla Indians Reservation in Palm Springs, CA. The Agua Caliente Band of Cahuilla Indians (ACBCI) conducted a feasibility and pre-development study of potential solar projects on its lands in southern California. As described below, this study as a logical and necessary next step for ACBCI. Support for solar project development in California, provided through the statewide California Solar Initiative (CSI), its Renewable Portfolio Standard and Feed-in Tariff Program, and recently announced Reverse Auction Mechanism, provide unprecedented support and incentives that can be utilized by customers of California's investor-owned utilities. Department of Energy (DOE) Tribal Energy Program funding allowed ACBCI to complete its next logical step to implement its Strategic Energy Plan, consistent with its energy and sustainability goals.

  5. ToHajiilee Economic Development, Inc.(TEDI) Feasibility Study for Utility-Scale Solar

    SciTech Connect (OSTI)

    Burpo, Rob

    2012-02-29

    To??Hajiilee Economic Development, Inc. (TEDI) is the economic development entity representing the ToHajiilee Chapter of the Navajo Nation, also known as the Ca??oncito Band of Navajo (CBN). Using DOE funding, TEDI assembled a team of qualified advisors to conduct a feasibility study for a utility-scale 30 MW Photovoltaic (PV) solar power generation facility on TEDI trust lands. The goal for this project has been to gather information and practical business commitments to successfully complete the feasibility analysis. The TEDI approach was to successively make informed decisions to select an appropriate technology best suited to the site, determine environmental viability of the site, secure options for the sale of generated power, determine practicality of transmission and interconnection of power to the local grid, and secure preliminary commitments on project financing. The feasibility study has been completed and provides TEDI with a practical understanding of its business options in moving forward with developing a solar project on CBN tribal lands. Funding from DOE has allowed TEDI and its team of professional advisors to carefully select technology and business partners and build a business model to develop this utility-scale solar project. As a result of the positive feasibility findings, TEDI is moving forward with finalizing all pre-construction activities for its major renewable energy project.

  6. DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    System Home, River Forest, IL | Department of Energy LLC, System Home, River Forest, IL DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC, System Home, River Forest, IL Case study of a DOE Zero Energy Ready Home in River Forest, IL, that scored HERS 17 without PV. This 4,763-square-foot custom passive house has R-54 ICF walls, a vented attic with R-100 blown fiberglass, plus R-40 rigid EPS under the slab, triple-pane windows, two ductless mini-split heat pumps, and

  7. DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC.,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Custom Home, Downers Grove, IL | Department of Energy LLC., Custom Home, Downers Grove, IL DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC., Custom Home, Downers Grove, IL Case study of a DOE Zero Energy Ready Home in Downers Grove, IL, that scored HERS 35 without PV. This 3,600-square-foot custom home has advanced framed walls with R-23 dense-packed fiberglass plus R-13 rigid polyiso, a sealed attic with open-cell spray foam, a pier foundation, and 95% efficient

  8. Very high numerical aperture light transmitting device

    DOE Patents [OSTI]

    Allison, Stephen W.; Boatner, Lynn A.; Sales, Brian C.

    1998-01-01

    A new light-transmitting device using a SCIN glass core and a novel calcium sodium cladding has been developed. The very high index of refraction, radiation hardness, similar solubility for rare earths and similar melt and viscosity characteristics of core and cladding materials makes them attractive for several applications such as high-numerical-aperture optical fibers and specialty lenses. Optical fibers up to 60 m in length have been drawn, and several simple lenses have been designed, ground, and polished. Preliminary results on the ability to directly cast optical components of lead-indium phosphate glass are also discussed as well as the suitability of these glasses as a host medium for rare-earth ion lasers and amplifiers.

  9. High numerical aperture multilayer Laue lenses

    SciTech Connect (OSTI)

    Morgan, Andrew J.; Prasciolu, Mauro; Andrejczuk, Andrzej; Krzywinski, Jacek; Meents, Alke; Pennicard, David; Graafsma, Heinz; Barty, Anton; Bean, Richard J.; Barthelmess, Miriam; Oberthuer, Dominik; Yefanov, Oleksandr; Aquila, Andrew; Chapman, Henry N.; Bajt, Saša

    2015-06-01

    The ever-increasing brightness of synchrotron radiation sources demands improved X-ray optics to utilise their capability for imaging and probing biological cells, nanodevices, and functional matter on the nanometer scale with chemical sensitivity. Here we demonstrate focusing a hard X-ray beam to an 8 nm focus using a volume zone plate (also referred to as a wedged multilayer Laue lens). This lens was constructed using a new deposition technique that enabled the independent control of the angle and thickness of diffracting layers to microradian and nanometer precision, respectively. This ensured that the Bragg condition is satisfied at each point along the lens, leading to a high numerical aperture that is limited only by its extent. We developed a phase-shifting interferometric method based on ptychography to characterise the lens focus. The precision of the fabrication and characterisation demonstrated here provides the path to efficient X-ray optics for imaging at 1 nm resolution.

  10. NUMERICAL MODELING OF CATHODE CONTACT MATERIAL DENSIFICATION

    SciTech Connect (OSTI)

    Koeppel, Brian J.; Liu, Wenning N.; Stephens, Elizabeth V.; Khaleel, Mohammad A.

    2011-11-01

    Numerical modeling was used to simulate the constrained sintering process of the cathode contact layer during assembly of solid oxide fuel cells (SOFCs). A finite element model based on the continuum theory for sintering of porous bodies was developed and used to investigate candidate low-temperature cathode contact materials. Constitutive parameters for various contact materials under investigation were estimated from dilatometry screening tests, and the influence of processing time, processing temperature, initial grain size, and applied compressive stress on the free sintering response was predicted for selected candidate materials. The densification behavior and generated stresses within a 5-cell planar SOFC stack during sintering, high temperature operation, and room temperature shutdown were predicted. Insufficient constrained densification was observed in the stack at the proposed heat treatment, but beneficial effects of reduced grain size, compressive stack preload, and reduced thermal expansion coefficient on the contact layer densification and stresses were observed.

  11. Numerical Investigation of Flapwise-Torsional Vibration Model of a Smart Section Blade with Microtab

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Nailu; Balas, Mark J.; Yang, Hua; Jiang, Wei; Magar, Kaman T.

    2015-01-01

    This study presents a method to develop an aeroelastic model of a smart section blade equipped with microtab. The model is suitable for potential passive vibration control study of the blade section in classic flutter. Equations of the model are described by the nondimensional flapwise and torsional vibration modes coupled with the aerodynamic model based on the Theodorsen theory and aerodynamic effects of the microtab based on the wind tunnel experimental data. The aeroelastic model is validated using numerical data available in the literature and then utilized to analyze the microtab control capability on flutter instability case and divergence instabilitymore » case. The effectiveness of the microtab is investigated with the scenarios of different output controllers and actuation deployments for both instability cases. The numerical results show that the microtab can effectively suppress both vibration modes with the appropriate choice of the output feedback controller.« less

  12. Demonstrating and implementing innovative technologies: Case studies from the USDOE Office of Technology Development

    SciTech Connect (OSTI)

    Brouns, T.M.; Koegler, K.J.; Mamiya, L.S.

    1995-02-01

    This paper describes elements of success for demonstration, evaluation, and transfer for deployment of innovative technologies for environmental restoration. They have been compiled from lessons learned through the US Department of Energy (DOE) Office of Technology Development`s Volatile Organic Compounds in Arid Soil Integrated Demonstration (VOC-Arid ID). The success of the VOC-Arid ID program was determined by the rapid development demonstration, and transfer for deployment of technologies to operational sites that improve on safety, cost, and/or schedule of performance over baseline technologies. The VOC-Arid ID successfully fielded more than 25 innovative technology field demonstrations; several of the technologies demonstrated have been successfully transferred for deployment Field demonstration is a critical element in the successful transfer of innovative technologies into environmental restoration operations. The measures of success for technology demonstrations include conducting the demonstration in a safe and controlled environment and generating the appropriate information by which to evaluate the technology. However, field demonstrations alone do not guarantee successful transfer for deployment There are many key elements throughout the development and demonstration process that have a significant impact on the success of a technology. This paper presents key elements for a successful technology demonstration and transfer for deployment identified through the experiences of the VOC-Arid ID. Also, several case studies are provided as examples.

  13. Mercury Speciation in Coal-Fired Power Plant Flue Gas-Experimental Studies and Model Development

    SciTech Connect (OSTI)

    Radisav Vidic; Joseph Flora; Eric Borguet

    2008-12-31

    The overall goal of the project was to obtain a fundamental understanding of the catalytic reactions that are promoted by solid surfaces present in coal combustion systems and develop a mathematical model that described key phenomena responsible for the fate of mercury in coal-combustion systems. This objective was achieved by carefully combining laboratory studies under realistic process conditions using simulated flue gas with mathematical modeling efforts. Laboratory-scale studies were performed to understand the fundamental aspects of chemical reactions between flue gas constituents and solid surfaces present in the fly ash and their impact on mercury speciation. Process models were developed to account for heterogeneous reactions because of the presence of fly ash as well as the deliberate addition of particles to promote Hg oxidation and adsorption. Quantum modeling was used to obtain estimates of the kinetics of heterogeneous reactions. Based on the initial findings of this study, additional work was performed to ascertain the potential of using inexpensive inorganic sorbents to control mercury emissions from coal-fired power plants without adverse impact on the salability fly ash, which is one of the major drawbacks of current control technologies based on activated carbon.

  14. Buildings of the Future Scoping Study: A Framework for Vision Development

    SciTech Connect (OSTI)

    Wang, Na; Goins, John D.

    2015-02-01

    The Buildings of the Future Scoping Study, funded by the U.S. Department of Energy (DOE) Building Technologies Office, seeks to develop a vision for what U.S. mainstream commercial and residential buildings could become in 100 years. This effort is not intended to predict the future or develop a specific building design solution. Rather, it will explore future building attributes and offer possible pathways of future development. Whether we achieve a more sustainable built environment depends not just on technologies themselves, but on how effectively we envision the future and integrate these technologies in a balanced way that generates economic, social, and environmental value. A clear, compelling vision of future buildings will attract the right strategies, inspire innovation, and motivate action. This project will create a cross-disciplinary forum of thought leaders to share their views. The collective views will be integrated into a future building vision and published in September 2015. This report presents a research framework for the vision development effort based on a literature survey and gap analysis. This document has four objectives. First, it defines the project scope. Next, it identifies gaps in the existing visions and goals for buildings and discusses the possible reasons why some visions did not work out as hoped. Third, it proposes a framework to address those gaps in the vision development. Finally, it presents a plan for a series of panel discussions and interviews to explore a vision that mitigates problems with past building paradigms while addressing key areas that will affect buildings going forward.

  15. Numerical simulation of transient, incongruent vaporization induced by high power laser

    SciTech Connect (OSTI)

    Tsai, C.H.

    1981-01-01

    A mathematical model and numerical calculations were developed to solve the heat and mass transfer problems specifically for uranum oxide subject to laser irradiation. It can easily be modified for other heat sources or/and other materials. In the uranium-oxygen system, oxygen is the preferentially vaporizing component, and as a result of the finite mobility of oxygen in the solid, an oxygen deficiency is set up near the surface. Because of the bivariant behavior of uranium oxide, the heat transfer problem and the oxygen diffusion problem are coupled and a numerical method of simultaneously solving the two boundary value problems is studied. The temperature dependence of the thermal properties and oxygen diffusivity, as well as the highly ablative effect on the surface, leads to considerable non-linearities in both the governing differential equations and the boundary conditions. Based on the earlier work done in this laboratory by Olstad and Olander on Iron and on Zirconium hydride, the generality of the problem is expanded and the efficiency of the numerical scheme is improved. The finite difference method, along with some advanced numerical techniques, is found to be an efficient way to solve this problem.

  16. The Numerical Tokamak Project (NTP) simulation of turbulent transport in the core plasma: A grand challenge in plasma physics

    SciTech Connect (OSTI)

    Not Available

    1993-12-01

    The long-range goal of the Numerical Tokamak Project (NTP) is the reliable prediction of tokamak performance using physics-based numerical tools describing tokamak physics. The NTP is accomplishing the development of the most advanced particle and extended fluid model`s on massively parallel processing (MPP) environments as part of a multi-institutional, multi-disciplinary numerical study of tokamak core fluctuations. The NTP is a continuing focus of the Office of Fusion Energy`s theory and computation program. Near-term HPCC work concentrates on developing a predictive numerical description of the core plasma transport in tokamaks driven by low-frequency collective fluctuations. This work addresses one of the greatest intellectual challenges to our understanding of the physics of tokamak performance and needs the most advanced computational resources to progress. We are conducting detailed comparisons of kinetic and fluid numerical models of tokamak turbulence. These comparisons are stimulating the improvement of each and the development of hybrid models which embody aspects of both. The combination of emerging massively parallel processing hardware and algorithmic improvements will result in an estimated 10**2--10**6 performance increase. Development of information processing and visualization tools is accelerating our comparison of computational models to one another, to experimental data, and to analytical theory, providing a bootstrap effect in our understanding of the target physics. The measure of success is the degree to which the experimentally observed scaling of fluctuation-driven transport may be predicted numerically. The NTP is advancing the HPCC Initiative through its state-of-the-art computational work. We are pushing the capability of high performance computing through our efforts which are strongly leveraged by OFE support.

  17. Winnebago Resource Study: Cooperative Research and Development Final Report, CRADA Number CRD-09-329

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Winnebago Resource Study Cooperative Research and Development Final Report CRADA Number: CRD-09-329 NREL Technical Contacts: Antonio Jimenez and Robi Robichaud CRADA Report NREL/TP-7A40-63933 March 2015 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (Alliance), a contractor of the US Government under Contract No. DE-AC36-08GO28308. Accordingly, the US Government and Alliance retain a nonexclusive royalty-free license to publish or

  18. Developing a Natural Gas-Powered Bus Rapid Transit Service: A Case Study

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Developing a Natural Gas- Powered Bus Rapid Transit Service: A Case Study George Mitchell National Renewable Energy Laboratory Technical Report NREL/TP-5400-64756 November 2015 NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency & Renewable Energy Operated by the Alliance for Sustainable Energy, LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. Contract No. DE-AC36-08GO28308

  19. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect (OSTI)

    Not Available

    1990-10-23

    The objectives of this program are to implement and test the process improvements identified through the engineering studies of the current program to demonstrate the capability of long-term catalyst activity maintenance, and to perform process and design engineering work that can be applied to a scaled-up Liquid Phase Methanol (LPMEOH) facility. An optional series of PDU runs is offered to extend the testing of the process improvements. A parallel research program will be performed to enhance the LPMEOH technical data base to improve the likelihood of commercialization of the LPMEOH process. Activities this quarter include: Flow sheet development for La Porte PDU modifications continues. A preliminary P ID review was completed and flow sheet modifications were identified and are being incorporated. A preliminary hazards review was completed on 22 May. Some minor flow sheet modifications resulted and a number of action items were identified. The most significant action item is to develop a materials reactivity and compatibility grid for the different alcohols, ethers, and esters which will be produced at the PDU. Heat and material balances were completed for the maximum production case of the mixed DME/MEOH synthesis campaign. An improved rate expression was developed. 1 fig.

  20. numerical modeling | OpenEI Community

    Open Energy Info (EERE)

    Submitted by Ocop(5) Member 15 July, 2014 - 07:07 MHK LCOE Reporting Guidance Draft Cost Current DOE LCOE numerical modeling Performance Tidal Wave To normalize competing...

  1. Government-promoted collective research and development in Japan: Analyses of the organization through case studies

    SciTech Connect (OSTI)

    Hane, G.J.

    1990-06-01

    A study was commissioned by the Energy Conservation and Utilization Technologies (ECUT) Program of the US Department of Energy (DOE) to better understand the strategies used for cooperative and joint-venture research and development (R D) overseas. The study evaluates the organization and management of several different types of cooperative R D programs in Japan that are sponsored under the Ministry of International Trade and Industry (MITI) Program, Exploratory Research for Advanced Technology (ERATO) Program, and the Key Technology Center (KTC) Program. The ERATO Program grew out of a concern over revising the government's approach to supporting research and technology development. The program was initiated to address what was regarded as a lack of creativity in areas at the forefront of science. The program recruits young researchers and allows them flexibility to explore multi-disciplinary areas at the forefront of science. It has been organized to allow for individual creativity but at the same time to benefit from the combined knowledge of an assembly of researchers. Because the plan is such a radical departure from conventional Japanese philosophy, it has met with certain bureaucratic obstacles. Visits to four ERATO projects are described. The third program, the KTC Program, focuses on getting private firms to venture into risky areas of advanced technology to pave the way for future industries. Its goal is to encourage a shift of resources in the private sector toward areas that are considered essential for the competitive development of future industries. The principal philosophy behind the KTC is that the private sector is in the best position to identify promising technical challenges and to weigh their commercial potential against research uncertainties. Three KTC research joint ventures are briefly described. 13 refs., 9 figs., 35 tabs.

  2. Study and Development of Anti-Islanding Control for Synchronous Machine-Based Distributed Generators: November 2001--March 2004

    SciTech Connect (OSTI)

    Ye, Z.

    2006-03-01

    This report summarizes the study and development of new active anti-islanding control schemes for synchronous machine-based distributed generators, including engine generators and gas turbines.

  3. Chombo-Crunch Case Study

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chombo-Crunch Case Study Chombo-Crunch Case Study Background Chombo-Crunch is a high-performance software package which has been developed jointly by research scientists from Applied Numerical Algorithms Group, Computational Research Division (PI: David Trebotich) and Earth Sciences Division at LBNL for large-scale numerical simulations of complex fluid flows with particular interest in modeling of subsurface flows. One important application example of subsurface flow is a carbon sequestration -

  4. Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation

    SciTech Connect (OSTI)

    Shirakashi, Ryo; Mischke, Miriam; Fischer, Peter; Memmel, Simon; Krohne, Georg; Fuhr, Guenter R.; Zimmermann, Heiko; Sukhorukov, Vladimir L.

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer Electrorotation offers a non-invasive tool for dielectric analysis of fish embryos. Black-Right-Pointing-Pointer The three-shell dielectric model matches the rotation spectra of medaka eggs. Black-Right-Pointing-Pointer The capacitance value suggests a double-membrane structure of yolk envelope. -- Abstract: The Japanese medaka fish, Oryzias latipes, has become a powerful vertebrate model organism in developmental biology and genetics. The present study explores the dielectric properties of medaka embryos during pre-hatching development by means of the electrorotation (ROT) technique. Due to their layered structure, medaka eggs exhibited up to three ROT peaks in the kHz-MHz frequency range. During development from blastula to early somite stage, ROT spectra varied only slightly. But as the embryo progressed to the late-somite stage, the ROT peaks underwent significant changes in frequency and amplitude. Using morphological data obtained by light and electron microscopy, we analyzed the ROT spectra with a three-shell dielectric model that accounted for the major embryonic compartments. The analysis yielded a very high value for the ionic conductivity of the egg shell (chorion), which was confirmed by independent osmotic experiments. A relatively low capacitance of the yolk envelope was consistent with its double-membrane structure revealed by transmission electron microscopy. Yolk-free dead eggs exhibited only one co-field ROT peak, shifted markedly to lower frequencies with respect to the corresponding peak of live embryos. The dielectric data may be useful for monitoring the development and changes in fish embryos' viability/conditions in basic research and industrial aquaculture.

  5. Science/art - art/science: case studies of the development of a professional art product

    SciTech Connect (OSTI)

    Sesko, S.C.; Marchant, M.

    1997-02-24

    Objective was to follow the cognitive and creative processes demonstrated by student research participants as they integrated a developing knowledge of ``big`` science, as practiced at LLNL, into a personal and idiosyncratic visual, graphical, or multimedia product. The participants, all non-scientists, involved in this process, attended a series of design classes, sponsored by LLNL at the Art Center College of Design in Pasadena CA. As a result of this study, we have become interested in the possibility of similar characteristics between scientists and artists. We have also become interested in the different processes that can be used to teach science to non-scientists, so that they are able to understand and portray scientific information.

  6. Development of remedial process options: Phase II, Feasibility study: Installation Restoration Program, Naval Air Station Fallon, Fallon, Nevada

    SciTech Connect (OSTI)

    Cronk, T.A.; Smuin, D.R.; Schlosser, R.M.

    1991-11-01

    This technical memorandum develops process options which are appropriate for environmental restoration activities at Naval Air Station Fallon (NAS Fallon), Nevada. Introduction of contaminants to the environment has resulted from deliberate disposal activities (both through dumping and landfilling) and accidental spills and leaks associated with normal activities at NAS Fallon over its lifetime of operation. Environmental sampling results indicate that the vast majority of contaminants of concern are petroleum hydrocarbon related. These contaminants include JP-4, JP-5, leaded and unleaded gasoline, waste oils and lubricants, hydraulic fluids, and numerous solvents and cleaners. The principal exposure pathways of concern associated with NAS Fallon contaminants appear to be the surface flows and shallow drainage systems to which the base contributes. Available data indicate NAS Fallon IR Program sites are not contributing excessive contamination to surface flows emanating from the base. Contaminants appear to be contained in a relatively immobile state in the shallow subsurface with little or no contaminant migration off site.

  7. On a framework for generating PoD curves assisted by numerical simulations

    SciTech Connect (OSTI)

    Subair, S. Mohamed Agrawal, Shweta Balasubramaniam, Krishnan Rajagopal, Prabhu; Kumar, Anish; Rao, Purnachandra B.; Tamanna, Jayakumar

    2015-03-31

    The Probability of Detection (PoD) curve method has emerged as an important tool for the assessment of the performance of NDE techniques, a topic of particular interest to the nuclear industry where inspection qualification is very important. The conventional experimental means of generating PoD curves though, can be expensive, requiring large data sets (covering defects and test conditions), and equipment and operator time. Several methods of achieving faster estimates for PoD curves using physics-based modelling have been developed to address this problem. Numerical modelling techniques are also attractive, especially given the ever-increasing computational power available to scientists today. Here we develop procedures for obtaining PoD curves, assisted by numerical simulation and based on Bayesian statistics. Numerical simulations are performed using Finite Element analysis for factors that are assumed to be independent, random and normally distributed. PoD curves so generated are compared with experiments on austenitic stainless steel (SS) plates with artificially created notches. We examine issues affecting the PoD curve generation process including codes, standards, distribution of defect parameters and the choice of the noise threshold. We also study the assumption of normal distribution for signal response parameters and consider strategies for dealing with data that may be more complex or sparse to justify this. These topics are addressed and illustrated through the example case of generation of PoD curves for pulse-echo ultrasonic inspection of vertical surface-breaking cracks in SS plates.

  8. Development and application of QM/MM methods to study the solvation effects and surfaces

    SciTech Connect (OSTI)

    Dibya, Pooja Arora

    2010-05-16

    Quantum mechanical (QM) calculations have the advantage of attaining high-level accuracy, however QM calculations become computationally inefficient as the size of the system grows. Solving complex molecular problems on large systems and ensembles by using quantum mechanics still poses a challenge in terms of the computational cost. Methods that are based on classical mechanics are an inexpensive alternative, but they lack accuracy. A good trade off between accuracy and efficiency is achieved by combining QM methods with molecular mechanics (MM) methods to use the robustness of the QM methods in terms of accuracy and the MM methods to minimize the computational cost. Two types of QM combined with MM (QM/MM) methods are the main focus of the present dissertation: the application and development of QM/MM methods for solvation studies and reactions on the Si(100) surface. The solvation studies were performed using a discreet solvation model that is largely based on first principles called the effective fragment potential method (EFP). The main idea of combining the EFP method with quantum mechanics is to accurately treat the solute-solvent and solvent-solvent interactions, such as electrostatic, polarization, dispersion and charge transfer, that are important in correctly calculating solvent effects on systems of interest. A second QM/MM method called SIMOMM (surface integrated molecular orbital molecular mechanics) is a hybrid QM/MM embedded cluster model that mimics the real surface.3 This method was employed to calculate the potential energy surfaces for reactions of atomic O on the Si(100) surface. The hybrid QM/MM method is a computationally inexpensive approach for studying reactions on larger surfaces in a reasonably accurate and efficient manner. This thesis is comprised of four chapters: Chapter 1 describes the general overview and motivation of the dissertation and gives a broad background of the computational methods that have been employed in this work. Chapter 2 illustrates the methodology of the interface of the EFP method with the configuration interaction with single excitations (CIS) method to study solvent effects in excited states. Chapter 3 discusses the study of the adiabatic electron affinity of the hydroxyl radical in aqueous solution and in micro-solvated clusters using a QM/EFP method. Chapter 4 describes the study of etching and diffusion of oxygen atom on a reconstructed Si(100)-2 x 1 surface using a hybrid QM/MM embedded cluster model (SIMOMM). Chapter 4 elucidates the application of the EFP method towards the understanding of the aqueous ionization potential of Na atom. Finally, a general conclusion of this dissertation work and prospective future direction are presented in Chapter 6.

  9. High numerical aperture multilayer Laue lenses

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Morgan, Andrew J.; Prasciolu, Mauro; Andrejczuk, Andrzej; Krzywinski, Jacek; Meents, Alke; Pennicard, David; Graafsma, Heinz; Barty, Anton; Bean, Richard J.; Barthelmess, Miriam; et al

    2015-06-01

    The ever-increasing brightness of synchrotron radiation sources demands improved X-ray optics to utilise their capability for imaging and probing biological cells, nanodevices, and functional matter on the nanometer scale with chemical sensitivity. Here we demonstrate focusing a hard X-ray beam to an 8 nm focus using a volume zone plate (also referred to as a wedged multilayer Laue lens). This lens was constructed using a new deposition technique that enabled the independent control of the angle and thickness of diffracting layers to microradian and nanometer precision, respectively. This ensured that the Bragg condition is satisfied at each point along themore » lens, leading to a high numerical aperture that is limited only by its extent. We developed a phase-shifting interferometric method based on ptychography to characterise the lens focus. The precision of the fabrication and characterisation demonstrated here provides the path to efficient X-ray optics for imaging at 1 nm resolution.« less

  10. Development of an ultrasonic pulse-echo (UPE) technique for aircraft icing studies

    SciTech Connect (OSTI)

    Liu, Yang; Hu, Hui; Chen, Wen-Li; Bond, Leonard J.

    2014-02-18

    Aircraft operating in some cold weather conditions face the risk of icing. Icing poses a threat to flight safety and its management is expensive. Removing light frost on a clear day from a medium-size business jet can cost $300, heavy wet snow removal can cost $3,000 and removal of accumulated frozen/freezing rain can cost close to $10,000. Understanding conditions that lead to severe icing events is important and challenging. When an aircraft or rotorcraft flies in a cold climate, some of the super cooled droplets impinging on exposed aircraft surfaces may flow along the surface prior to freezing and give various forms and shapes of ice. The runback behavior of a water film on an aircraft affects the morphology of ice accretion and the rate of formation. In this study, we report the recent progress to develop an Ultrasonic Pulse-Echo (UPE) technique to provide real-time thickness distribution measurements of surface water flows driven by boundary layer airflows for aircraft icing studies. A series of initial experimental investigations are conducted in an ice wind tunnel employing an array of ultrasonic transducers placed underneath the surface of a flat plate. The water runback behavior on the plate is evaluated by measuring the thickness profile variation of the water film along the surface by using the UPE technique under various wind speed and flow rate conditions.

  11. Powder River Basin Coalbed Methane Development and Produced Water Management Study

    SciTech Connect (OSTI)

    Advanced Resources International

    2002-11-30

    Coalbed methane resources throughout the entire Powder River Basin were reviewed in this analysis. The study was conducted at the township level, and as with all assessments conducted at such a broad level, readers must recognize and understand the limitations and appropriate use of the results. Raw and derived data provided in this report will not generally apply to any specific location. The coal geology in the basin is complex, which makes correlation with individual seams difficult at times. Although more than 12,000 wells have been drilled to date, large areas of the Powder River Basin remain relatively undeveloped. The lack of data obviously introduces uncertainty and increases variability. Proxies and analogs were used in the analysis out of necessity, though these were always based on sound reasoning. Future development in the basin will make new data and interpretations available, which will lead to a more complete description of the coals and their fluid flow properties, and refined estimates of natural gas and water production rates and cumulative recoveries. Throughout the course of the study, critical data assumptions and relationships regarding gas content, methane adsorption isotherms, and reservoir pressure were the topics of much discussion with reviewers. A summary of these discussion topics is provided as an appendix. Water influx was not modeled although it is acknowledged that this phenomenon may occur in some settings. As with any resource assessment, technical and economic results are the product of the assumptions and methodology used. In this study, key assumptions as well as cost and price data, and economic parameters are presented to fully inform readers. Note that many quantities shown in various tables have been subject to rounding; therefore, aggregation of basic and intermediate quantities may differ from the values shown.

  12. Standing Rock Sioux Tribe - Lakota/Dakota Nation Feasibility Study Supporting Wind Development and Establishment of Renewable Energy and Energy Development Office

    Energy Savers [EERE]

    (Washee Zee) 701-854-3437 fwasinzi@standingrock.org Standing Rock Sioux Tribe - Lakota/Dakota Nation  BACKGROUND INFORMATION ON STANDING ROCK RESERVATION  SITTING BULL COLLEGE WIND TURBINE  EECBG ENERGY EFFICIENCY & WIND TURBINE INSTALLATION AT SITTING BULL COLLEGE  WIND ASSESSMENT STUDY  ESTABLISHMENT OF RENEWABLE ENERGY & ENERGY DEVELOPMENT OFFICE (REEDO)  WIND FEASIBILITY STUDY  OCETI SAKOWIN POWER PROJECT  ONE OF SEVEN RESERVATIONS OF THE GREAT SIOUX NATION

  13. Theoretical, numerical and experimental investigation of centrifugal pumps in reverse operation

    SciTech Connect (OSTI)

    Derakhshan, Shahram; Nourbakhsh, Ahmad

    2008-09-15

    When a pump works as a turbine, its hydraulic behavior will be changed. Several methods have been developed to predict the best efficiency of pumps running as turbines but their results are not in good coincidence with experimental data for all pumps. Therefore, study and investigation of hydraulic behavior of pumps in reverse operation can be useful. In this study, the best efficiency point of an industrial centrifugal pump running as turbine was achieved using a theoretical analysis. This method tries to estimate hydraulic components of reverse (turbine) mode using direct (pump) mode. In the next step, the pump was simulated in direct and reverse modes by computational fluid dynamics. 3D full Navier-Stokes equations were solved using FineTurbo V.7 flow solver. Using numerical results, complete characteristic curves of the pump in direct and reverse modes were obtained. For experimental verification of theoretical and numerical results, the pump was tested as a turbine in a test rig. All required parameters were measured to achieve complete characteristic curves of the reverse pump. The theoretical and numerical results were compared with experimental data and some other methods. (author)

  14. Numerical description of cavitation on axisymmetric bodies

    SciTech Connect (OSTI)

    Hickox, C.E.; Hailey, C.E.; Wolfe, W.P.; Watts, H.A.; Gross, R.J.; Ingber, M.S.

    1988-01-01

    This paper reports on ongoing studies which are directed toward the development of predictive techniques for the modeling of steady cavitation on axisymmetric bodies. The primary goal of the modeling effort is the prediction of cavity shape and pressure distribution from which forces and moments can be calculated. Here we present an overview of the modeling techniques developed and compare predictions with experimental data obtained from water tunnel tests for both limited and supercavitation. 14 refs., 4 figs.

  15. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect (OSTI)

    Not Available

    1991-01-02

    Liquid-entrained operations at the LaPorte Liquid Phase Methanol (LPMEOH) Process Development Unit (PDU) continued during June and July 1988 under Tasks 2.1 and 2.2 of Contract No. DE-AC22-87PC90005 for the US Department of Energy. The primary focus of this PDU operating program was to prepare for a confident move to the next scale of operation with an optimized and simplified process. Several new design options had been identified and thoroughly evaluated in a detailed process engineering study completed under the LPMEOH Part-2 contract (DE-AC22-85PC80007), which then became the basis for the current PDU modification/operating program. The focus of the Process Engineering Design was to optimize and simplifications focused on the slurry loop, which consists of the reactor, vapor/liquid separator, slurry heat exchanger, and slurry circulation pump. Two-Phase Gas Holdup tests began at LaPorte in June 1988 with nitrogen/oil and CO- rich gas/oil systems. The purpose of these tests was to study the hydrodynamics of the reactor, detect metal carbonyl catalyst poisons, and train operating personnel. Any effect of the new gas sparger and the internal heat exchanger would be revealed by comparing the hydrodynamic data with previous PDU hydrodynamic data. The Equipment Evaluation'' Run E-5 was conducted at the LaPorte LPMEOH PDU in July 1988. The objective of Run E-5 was to systematically evaluate each new piece of equipment (sparger, internal heat exchanger, V/L disengagement zone, demister, and cyclone) which had been added to the system, and attempt to run the reactor in an internal-only mode. In addition, a successful catalyst activation with a concentrated (45 wt % oxide) slurry was sought. 9 refs., 26 figs., 15 tabs.

  16. Studies on the development of mossy zinc electrodeposits from flowing alkaline electrolytes

    SciTech Connect (OSTI)

    Mc Vay, L.

    1991-07-01

    The initiation and characteristics of mossy zinc electrodeposits have been investigated. Batteries with zinc electrodes are candidates for electric vehicle applications; however, this electrode is prone to form non-compact deposits that contribute to capacity loss and battery failure. Moss is deposited when the current density is far from the limiting current. This morphology first appears only after the bulk deposit is approximately 1 {mu}m thick. In this investigation, the effects of flow rate (Re=0--4000), current density (0--50 mA/cm{sup 2}), concentration of the electroactive species (0.25 and 0.5 M), and the concentration of supporting electrolyte (3, 6, and 12 M) on the initiation of moss were examined. The rotating concentric cylinder electrode was employed for most of the experiments; and a flow channel was used to study the development of morphology. After the experiment, the deposit was characterized using microscopic, x-ray diffraction, and profilometric techniques. 94 refs., 72 figs.

  17. Modeling and Testing Miniature Torsion Specimens for SiC Joining Development Studies for Fusion

    SciTech Connect (OSTI)

    Henager, Charles H.; Nguyen, Ba Nghiep; Kurtz, Richard J.; Roosendaal, Timothy J.; Borlaug, Brennan A.; Ferraris, Monica; Ventrella, Andrea; Katoh, Yutai

    2015-08-19

    The international fusion community has designed a miniature torsion specimen for neutron irradiation studies of joined SiC and SiC/SiC composite materials. Miniature torsion joints based on this specimen design were fabricated using displacement reactions between Si and TiC to produce Ti3SiC2 + SiC joints with CVD-SiC and tested in torsion-shear prior to and after neutron irradiation. However, many of these miniature torsion specimens fail out-of-plane within the CVD-SiC specimen body, which makes it problematic to assign a shear strength value to the joints and makes it difficult to compare unirradiated and irradiated joint strengths to determine the effects of the irradiation. Finite element elastic damage and elastic-plastic damage models of miniature torsion joints are developed that indicate shear fracture is likely to occur within the body of the joined sample and cause out-of-plane failures for miniature torsion specimens when a certain modulus and strength ratio between the joint material and the joined material exists. The model results are compared and discussed with regard to unirradiated and irradiated joint test data for a variety of joint materials. The unirradiated data includes Ti3SiC2 + SiC/CVD-SiC joints with tailored joint moduli, and includes steel/epoxy and CVD-SiC/epoxy joints. The implications for joint data based on this sample design are discussed.

  18. Laboratory Experiments and Instrument Development for the Study of Atmospheric Aerosols

    SciTech Connect (OSTI)

    Davidovits, Paul

    2011-12-10

    Soot particles are generated by incomplete combustion of fossil and biomass fuels. Through direct effects clear air aerosols containing black carbon (BC) such as soot aerosols, absorb incoming light heating the atmosphere, while most other aerosols scatter light and produce cooling. Even though BC represents only 1-2% of the total annual emissions of particulate mass to the atmosphere, it has been estimated that the direct radiative effect of BC is the second-most important contributor to global warming after absorption by CO2. Ongoing studies continue to underscore the climate forcing importance of black carbon. However, estimates of the radiative effects of black carbon on climate remain highly uncertain due to the complexity of particles containing black carbon. Quantitative measurement of BC is challenging because BC often occurs in highly non-spherical soot particles of complex morphology. Freshly emitted soot particles are typically fractal hydrophobic aggregates. The aggregates consist of black carbon spherules with diameters typically in the range of about 15-40 nm, and they are usually coated by adsorbed polyaromatic hydrocarbons (PAHs) produced during combustion. Diesel-generated soot particles are often emitted with an organic coating composed primarily of lubricating oil and unburned fuel, as well as well as PAH compounds. Sulfuric acid has also been detected in diesel and aircraft-emitted soot particles. In the course of aging, these particle coatings may be substantially altered by chemical reactions and/or the deposition of other materials. Such processes transform the optical and CCN properties of the soot aerosols in ways that are not yet well understood. Our work over the past seven years consisted of laboratory research, instrument development and characterization, and field studies with the central focus of improving our understanding of the black carbon aerosol climate impacts. During the sixth year as well as during this seventh year (no-cost extension period) of our grant, we extended our studies to perform experiments on the controlled production and characterization of secondary organic aerosol.

  19. Numerical solution of sand transport in hydraulic fracturing

    SciTech Connect (OSTI)

    Daneshy, A.A.; Crichlow, H.B.

    1980-02-07

    A numerical solution is developed for the deposition of a propping agent inside a hydraulic fracture. Such parameters as fluid leak-off into the formation, increase in sand concentration caused by leak-off, non-Newtonian fracturing fluids, hindered settling velocity, and an up-to-date geometry are taken into consideration. Three examples investigate the proppant deposition for low-, medium-, and high-viscosity fracturing fluids.

  20. Numerical Simulation of Groundwater Withdrawal at the Nevada Test Site

    SciTech Connect (OSTI)

    Carroll, Rosemary; Giroux, Brian; Pohll, Greg; Hershey, Ronald; Russell, Charles; Howcroft, William

    2004-01-28

    Alternative uses of the Nevada Test Site (NTS) may require large amounts of water to construct and/or operate. The only abundant source of water at the NTS is groundwater. This report describes preliminary modeling to quantify the amount of groundwater available for development from three hydrographic areas at the NTS. Modeling was conducted with a three-dimensional transient numerical groundwater flow model.

  1. Sodium-Water Reaction and Thermal Hydraulics at Gas-Liquid Interface: Numerical Interpretation of Experimental Observations

    SciTech Connect (OSTI)

    Yamaguchi, Akira; Takata, Takashi; Ohshima, Hiroyuki; Suda, Kazunori

    2006-07-01

    In a sodium-cooled fast reactor development, coupled phenomena of thermal-hydraulics and chemical reaction of sodium and water vapor are of importance from the safety viewpoint. However, the sodium-water reaction (SWR) phenomena are generally complex and the experimental measurement technology is not well matured. Therefore, a numerical simulation is used for the investigation of the SWR. In this paper, a new computer program has been developed and the SWR in a counter-flow diffusion flame is studied by a numerical simulations and an experiment as well. In the computer program, Navier-Stokes equations and chemical reaction equations are solved interactively. In addition, a dynamic equation of airborne particulates is coupled with the governing equations of thermal hydraulics. A source of the particulates is the chemical reaction products, i.e. sodium hydroxide and sodium oxide. The SWR experiment is decided based on the numerical simulation. To obtain a stable reaction flame and to measure the temperature and reaction product distributions, the flow field in the experimental cell needs to be optimized. The numerical simulation is useful for designing experiments of complex phenomena and for obtaining the data. The computations are compared with experimental data. It has been demonstrated that the computational fluid dynamics code coupled with chemical reaction well predict the SWR. (authors)

  2. The study on knowledge transferring incentive for information system requirement development

    SciTech Connect (OSTI)

    Li, Yang

    2015-03-10

    Information system requirement development is a process of users’ knowledge sharing and transferring. However the tacit requirements developing is a main problem during requirement development process, for the reason of difficult to encoding, express, and communicate. Knowledge fusion and corporate effort is needed to finding tacit requirements. Under this background, our paper try to find out the rule of effort dynamic evolutionary of software developer and user by building an evolutionary game model on the condition of incentive system. And in addition this paper provides an in depth discussion at the end of this paper.

  3. Liquid phase methanol LaPorte process development unit: Modification, operation, and support studies

    SciTech Connect (OSTI)

    Not Available

    1990-11-09

    As part of the liquid phase methanol process development program the present study evaluated adsorptive schemes to remove catalyst poisons from coal gas at pilot scale. In addition to a lab test with coal gas from Coolwater, two field tests were performed at Great Plains with live coal gas. In the lab with Coolwater, gas iron carbonyl, carbonyl sulfide,and hydrogen sulfide were effectively removed from the coal gas. The capacities of H-Y zeolite and BPL carbon for Fe(CO){sub 5} agreed well with the previous bench scale results at similar CO{sub 2} partial pressure. COS appeared to be chemisorbed on FCA carbon; its capacity was non-regenerable by hot nitrogen purge. A Cu/Zn catalyst, used to remove H{sub 2}S adsorptively, worked adequately. With the adsorption system on-line, a downstream methanol catalyst showed stable activity for 120 hours of operation. In the two field tests, it was demonstrated that the Great Plains (GP) syngas could be treated by adsorption for LPMEOH process. The catalyst deactivation observed in the first field test was much improved in the second field test after regular (every three days) regeneration of the adsorbents was practiced. The absorption system, which was designed for the removal of iron/nickel carbonyls, hydrogen/carbonyl sulfide and hydrochloric acid, needed to be modified to accommodate other unexpected impurities, such as acetonitrile and ethylene which were observed during both field tests. A lab test with a simulated GP gas indicated that low CO{sub 2} content (0.5%) in the GP gas does not cause catalyst deactivation. Adjusting the CO{sub 2} content of the feed to 5% by CO{sub 2} addition, increased methanol productivity by 40% in both the lab and the second field test. 6 refs., 25 figs., 14 tabs.

  4. Recent developments in atomic/nuclear methodologies used for the study of cultural heritage objects

    SciTech Connect (OSTI)

    Appoloni, Carlos Roberto

    2013-05-06

    Archaeometry is an area established in the international community since the 60s, with extensive use of atomic-nuclear methods in the characterization of art, archaeological and cultural heritage objects in general. In Brazil, however, until the early '90s, employing methods of physics, only the area of archaeological dating was implemented. It was only after this period that Brazilian groups became involved in the characterization of archaeological and art objects with these methodologies. The Laboratory of Applied Nuclear Physics, State University of Londrina (LFNA/UEL) introduced, pioneered in 1994, Archaeometry and related issues among its priority lines of research, after a member of LFNA has been involved in 1992 with the possibilities of tomography in archaeometry, as well as the analysis of ancient bronzes by EDXRF. Since then, LFNA has been working with PXRF and Portable Raman in several museums in Brazil, in field studies of cave paintings and in the laboratory with material sent by archaeologists, as well as carrying out collaborative work with new groups that followed in this area. From 2003/2004 LAMFI/DFN/IFUSP and LIN/COPPE/UFRJ began to engage in the area, respectively with methodologies using ion beams and PXRF, then over time incorporating other techniques, followed later by other groups. Due to the growing number of laboratories and institutions/archaeologists/conservators interested in these applications, in may 2012 was created a network of available laboratories, based at http://www.dfn.if.usp.br/lapac. It will be presented a panel of recent developments and applications of these methodologies by national groups, as well as a sampling of what has been done by leading groups abroad.

  5. Development of analytical techniques to study H2s poisoning of PEMFCs and components

    SciTech Connect (OSTI)

    Brosha, Eric L; Rockward, Tommy; Uribe, Francisco A; Garzon, Fernando H

    2008-01-01

    Polymer electrolyte membrane fuel cells are sensitive to impurities that may be present in either the oxidizer or fuel. H{sub 2}S, even at the ppb level, will have a dramatic and adverse affect on fuel cell performance. Not only is it important to know a particular material's affinity to adsorb H{sub 2}S, when considering materials for PEMFC applications, issues such as permeation and crossover rates also become extremely important Several experimental methods have been developed to quantify H{sub 2}S adsorption onto surfaces and to quantify H{sub 2}S permeation through Nafion(reg.) membranes using readily available and inexpensive Ag/AgS ion probes. In addition to calculating the H{sub 2}S uptake on commonly used XC-72 carbon supports and PtlXC-72 catalysts, the H{sub 2}S permeability through dry and humidified Nafion(reg.) PEMFC membranes was also studied using these specialized techniques. In each ion probe experiment performed, a sulfide anti-oxidant buffer solution was used to trap and concentrate trace quantities of H{sub 2}S during the course of the measurement. Crossover experiments were conducted for up to 24 hours in order to achieve sulfide ion concentrations high enough to be precisely determined by subsequent titration with Pb(NO{sub 3}){sub 2}. By using these techniques, we have confirmed H{sub 2}S crossover in Nafion(reg.) membranes and have calculated preliminary rates of H{sub 2}S crossover.

  6. Combined experimental and numerical evaluation of a prototype nano-PCM enhanced wallboard

    SciTech Connect (OSTI)

    Biswas, Kaushik; LuPh.D., Jue; Soroushian, Parviz; Shrestha, Som S

    2014-01-01

    In the United States, forty-eight (48) percent of the residential end-use energy consumption is spent on space heating and air conditioning. Reducing envelope-generated heating and cooling loads through application of phase change material (PCM)-enhanced building envelopes can facilitate maximizing the energy efficiency of buildings. Combined experimental testing and numerical modeling of PCM-enhanced envelope components are two important aspects of the evaluation of their energy benefits. An innovative phase change material (nano-PCM) was developed with PCM encapsulated with expanded graphite (interconnected) nanosheets, which is highly conductive for enhanced thermal storage and energy distribution, and is shape-stable for convenient incorporation into lightweight building components. A wall with cellulose cavity insulation and prototype PCM-enhanced interior wallboards was built and tested in a natural exposure test (NET) facility in a hot-humid climate location. The test wall contained PCM wallboards and regular gypsum wallboard, for a side-by-side annual comparison study. Further, numerical modeling of the walls containing the nano-PCM wallboard was performed to determine its actual impact on wall-generated heating and cooling loads. The model was first validated using experimental data, and then used for annual simulations using Typical Meteorological Year (TMY3) weather data. This article presents the measured performance and numerical analysis evaluating the energy-saving potential of the nano-PCM-enhanced wallboard.

  7. Public service impacts of geothermal development: cumulative impacts study of the Geysers KGRA. Final staff report

    SciTech Connect (OSTI)

    Matthews, K.M.

    1983-07-01

    The number of workers currently involved in the various aspects of geothermal development in the Geysers are identified. Using two different development scenarios, projections are made for the number of power plants needed to reach the electrical generation capacity of the steam resource in the Geysers. The report also projects the cumulative number of workers needed to develop the steam field and to construct, operate, and maintain these power plants. Although the number of construction workers fluctuates, most are not likely to become new, permanent residents of the KGRA counties. The administrative and public service costs of geothermal development to local jurisdications are examined, and these costs are compared to geothermal revenues accruing to the local governments. Revenues do not cover the immediate fiscal needs resulting from increases in local road maintenance and school enrollment attributable to geothermal development. Several mitigation options are discussed and a framework presented for calculating mitigation costs for school and road impacts.

  8. Direct Numerical Simulation of Pore-Scale Flow in a Bead Pack: Comparison with Magnetic Resonance Imaging Observations

    SciTech Connect (OSTI)

    Yang, Xiaofan; Scheibe, Timothy D.; Richmond, Marshall C.; Perkins, William A.; Vogt, Sarah J.; Codd, Sarah L.; Seymour, Joseph D.; Mckinley, Matthew I.

    2013-04-01

    A significant body of current research is aimed at developing methods for numerical simulation of flow and transport in porous media that explicitly resolve complex pore and solid geometries, and at utilizing such models to study the relationships between fundamental pore-scale processes and macroscopic manifestations at larger (i.e., Darcy) scales. A number of different numerical methods for pore-scale simulation have been developed, and have been extensively tested and validated for simplified geometries. However, validation of pore-scale simulations of fluid velocity for complex, three-dimensional (3D) pore geometries that are representative of natural porous media is challenging due to our limited ability to measure pore-scale velocity in such systems. Recent advances in magnetic resonance imaging (MRI) offer the opportunity to measure not only the pore geometry, but also local fluid velocities under steady-state flow conditions in 3D and with high spatial resolution. In this paper, we present a 3D velocity field measured at sub-pore resolution (tens of micrometers) over a centimeter-scale 3D domain using MRI methods. We have utilized the measured pore geometry to perform 3D simulations of Navier-Stokes flow over the same domain using direct numerical simulation techniques. We present a comparison of the numerical simulation results with the measured velocity field. It is shown that the numerical results match the observed velocity patterns well overall except for a variance and small systematic scaling which can be attributed to the known experimental error in the MRI measurements. The comparisons presented here provide strong validation of the pore-scale simulation methods and new insights for interpretation of uncertainty in MRI measurements of pore-scale velocity. This study also provides a potential benchmark for future comparison of other pore-scale simulation methods.

  9. WindFloat Feasibility Study Support. Cooperative Research and Development Final Report, CRADA Number CRD-11-419

    SciTech Connect (OSTI)

    Sirnivas, Senu

    2015-05-07

    This shared resource CRADA defines research collaborations between the National Renewable Energy Laboratory and Principle Power, Inc. and its subsidiaries (“Principle Power”). Under the terms and conditions described in this CRADA agreement, NREL and Principle Power will collaborate on the DEMOWFLOAT project, a full-scale 2-MW demonstration project of a novel floating support structure for large offshore wind turbines, called WindFloat. The purpose of the project is to demonstrate the longterm field performance of the WindFloat design, thus enabling the future commercialized deployment of floating deepwater offshore wind power plants. NREL is the leading U.S. Department of Energy (DOE) laboratory for the development and advancement of renewable energy and has a strong interest in offshore wind and the development of deepwater offshore wind systems. NREL will provide expertise and resources to the DEMOWFLOAT project in assessing the environmental impacts, independent technical performance validation, and engineering analysis. Principle Power is a Seattle, Washington-based renewable energy company that owns all the intellectual property associated with the WindFloat. In return for NREL’s support of the DEMOWFLOAT project, Principle Power will provide NREL with valuable test data from the project that will be used to validate the numerical tools developed by NREL for analyzing offshore wind turbines. In addition, NREL will gain experience and knowledge in offshore wind designs and testing methods through this collaboration. 2 This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. NREL and Principle Power will work together to advance floating offshore wind technology, and demonstrate its viability for supplying the world with a new clean energy source.

  10. Advanced LWR Nuclear Fuel Cladding System Development Trade-Off Study

    SciTech Connect (OSTI)

    Kristine Barrett; Shannon Bragg-Sitton

    2012-09-01

    The Advanced Light Water Reactor (LWR) Nuclear Fuel Development Research and Development (R&D) Pathway encompasses strategic research focused on improving reactor core economics and safety margins through the development of an advanced fuel cladding system. To achieve significant operating improvements while remaining within safety boundaries, significant steps beyond incremental improvements in the current generation of nuclear fuel are required. Fundamental improvements are required in the areas of nuclear fuel composition, cladding integrity, and the fuel/cladding interaction to allow power uprates and increased fuel burn-up allowance while potentially improving safety margin through the adoption of an “accident tolerant” fuel system that would offer improved coping time under accident scenarios. With a development time of about 20 – 25 years, advanced fuel designs must be started today and proven in current reactors if future reactor designs are to be able to use them with confidence.

  11. DOE Zero Energy Ready Home Case Study 2013: StreetScape Development...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... McLinden invited Susanka to participate in the development after reading her books. ... As the builder McLinden states: "So many people buy things, like electronic equipment with ...

  12. DOE Zero Energy Ready Home Case Study: StreetScape Development, LLC, Libertyville, Illinois

    SciTech Connect (OSTI)

    none,

    2013-09-01

    These single-family, HERS 45 homes incorporate 2×6 wood framed walls with R-20 open cell spray insulation and OSB. The builder, StreetScape Development, won a 2013 Housing Innovation Award in the custom builder category.

  13. Comparison of effectiveness of sub-slab ventilation systems for indoor radon mitigation: A numerical study; Comparaison a l`aide d`un outil numerique de l`efficacite des systemes de ventilation active du sol limitant la penetration du radon dans l`habitat

    SciTech Connect (OSTI)

    Bonnefous, Y.C. |; Gadgil, A.J.; Allard, F.

    1992-04-01

    The functioning of an active sub-slab ventilation system (SVS) has been studied successfully with the help of a previously evaluated numerical model. The parameters explored are the permeability of the sub-slab and the gravel placed beneath it, the amplitude of applied pressure at the installation point of the system and the functioning method: depressurization or pressurization. The mechanisms contributing to the success of the two systems are identified. This numerical study shows that the presence of a layer of gravel beneath the sub-slab considerably improves the performance of the SVS. Considered separately from the extremely permeable sub-slabs, the depressurization systems perform better than the pressurization systems. 17 refs. [Francais] Le fonctionnement des Systemes de Ventilation active du Sol (SVS) a ete etudie a l`aide d`un outil numerique precedemment evalue avec succes. Les parametres explores sont les permeabilites du sol et du gravier place sous plancher bas, l`amplitude de la pression appliquee au point d`installation du systeme, et le mode de fonctionnement: Depressurisation ou Pressurisation. Les mecanismes contribuant au succes des deux systemes sont identifies. Cette etude numerique montre que la presence d`une couche de gravier sous plancher bas ameliore de facon considerable les performances des SVS. Mis a part le cas des sols extremement permeables, les systemes de Depressurisation ont de meilleures performances que les systemes de Pressurisation. 17 refs.

  14. Vegetation component of geothermal EIS studies: Introduced plants, ecosystem stability, and geothermal development

    SciTech Connect (OSTI)

    1994-10-01

    This paper contributes new information about the impacts from introduced plant invasions on the native Hawaiian vegetation as consequences of land disturbance and geothermal development activities. In this regard, most geothermal development is expected to act as another recurring source of physical disturbance which favors the spread and maintenance of introduced organisms throughout the region. Where geothermal exploration and development activities extend beyond existing agricultural and residential development, they will become the initial or sole source of disturbance to the naturalized vegetation of the area. Kilauea has a unique ecosystem adapted to the dynamics of a volcanically active landscape. The characteristics of this ecosystem need to be realized in order to understand the major threats to the ecosystem and to evaluate the effects of and mitigation for geothermal development in Puna. The native Puna vegetation is well adapted to disturbances associated with volcanic eruption, but it is ill-adapted to compete with alien plant species in secondary disturbances produced by human activities. Introduced plant and animal species have become a major threat to the continued presence of the native biota in the Puna region of reference.

  15. On Numerical Considerations for Modeling Reactive Astrophysical Shocks

    SciTech Connect (OSTI)

    Papatheodore, Thomas L; Messer, Bronson

    2014-01-01

    Simulating detonations in astrophysical environments is often complicated by numerical approximations to shock structure. A common prescription to ensure correct detonation speeds (and associated quantities) is to prohibit burning inside the numerically broadened shock (Fryxell et al. 1989). We have performed a series of simulations to verify the efficacy of this approximation and to understand how resolution and dimensionality might affect its use. Our results show that, in one dimension, prohibiting burning in the shock is important wherever the carbon burning length is not resolved, in keeping with the results of Fryxell et al. (1989). In two dimensions, we find that the prohibition of shock burning effectively inhibits the development of cellular structure for all but the most highly-resolved cases. We discuss the possible impacts this outcome may have on sub-grid models and detonation propagation in Type Ia supernovae.

  16. Low-rank coal study: national needs for resource development. Volume 3. Technology evaluation

    SciTech Connect (OSTI)

    Not Available

    1980-11-01

    Technologies applicable to the development and use of low-rank coals are analyzed in order to identify specific needs for research, development, and demonstration (RD and D). Major sections of the report address the following technologies: extraction; transportation; preparation, handling and storage; conventional combustion and environmental control technology; gasification; liquefaction; and pyrolysis. Each of these sections contains an introduction and summary of the key issues with regard to subbituminous coal and lignite; description of all relevant technology, both existing and under development; a description of related environmental control technology; an evaluation of the effects of low-rank coal properties on the technology; and summaries of current commercial status of the technology and/or current RD and D projects relevant to low-rank coals.

  17. Low-rank coal study: national needs for resource development. Volume 6. Peat

    SciTech Connect (OSTI)

    Not Available

    1980-11-01

    The requirements and potential for development of US peat resources for energy use are reviewed. Factors analyzed include the occurrence and properties of major peat deposits; technologies for extraction, dewatering, preparation, combustion, and conversion of peat to solid, liquid, or gaseous fuels; environmental, regulatory, and market constraints; and research, development, and demonstration (RD and D) needs. Based on a review of existing research efforts, recommendations are made for a comprehensive national RD and D program to enhance the use of peat as an energy source.

  18. GIS solutions for ecosystem management in developing countries: A case study of Sao Tome and Principe

    SciTech Connect (OSTI)

    Barnes, L.; Barrasso, T.; Pinto da Costa, H.

    1995-12-01

    The purpose of this paper is to promote awareness of the application of the Geographic information system (GIS) technology to the management of ecosystems in developing countries. The adoptation of systematic environmental research and management techniques by national and local conservation programs helps ensure the sustainability of important biological resources.

  19. Winnebago Resource Study. Cooperative Research and Development Final Report, CRADA Number CRD-09-329

    SciTech Connect (OSTI)

    Jimenez, A.; Robichaud, R.

    2015-03-01

    Since 2005 the NREL Native American Tall Tower Loan program has assisted Native American tribes to assess their wind resource by lending tall (30m - 50m) anemometer. This program has allowed tribes a lower risk way to gather financeable wind data for potential utility scale wind energy projects. These projects offer Tribes a significant economic development opportunity.

  20. DOE Zero Energy Ready Home Case Study: Brookside Development — Singer Village, Derby, CT

    SciTech Connect (OSTI)

    none,

    2014-09-01

    This DOE Zero Energy Ready Home is one of a development of seven two-story homes that garnered a Production Builder award in the 2014 Housing Innovation Awards. Exceptional construction quality allowed the home to achieve a HERS score of 45 without photovoltaic, or HERS 26 with a 7-kW photovoltaic system included.

  1. FE-Funded Study Released on Key Factors Affecting China Shale Gas Development

    Broader source: Energy.gov [DOE]

    As many people know, over the past decade the United States has experienced a shale gas revolution that has beneficially transformed its energy landscape. In witnessing this transformation, other nations with significant shale resources are understandably interested in pursuing the responsible development of their domestic reserves, and achieving for their people accompanying economic, energy security and environmental benefits.

  2. SOLVENT-BASED ENHANCED OIL RECOVERY PROCESSES TO DEVELOP WEST...

    Office of Scientific and Technical Information (OSTI)

    The experimental study is designed to foster understanding of the processes governing ... Numerical simulation study of VAPEX was initiated during the first year. The numerical ...

  3. DOE Zero Energy Ready Home Case Study: Weiss Building & Development, Downers Grove, Illinois

    SciTech Connect (OSTI)

    none,

    2013-09-01

    This single-family home built in a peat bog has underground storage tanks and drainage tanks, blown fiberglass insulation, coated rigid polyisocyanurate, and flashing. The 3,600-square-foot custom home built by Weiss Building & Development LLC is the first home in Illinois certified to the DOE Challenge Home criteria, which requires that homes meet the EPA Indoor airPlus guidelines.The builder won a 2013 Housing Innovation Award in the custom builder category.

  4. Calendar Life Studies of Advanced Technology Development Program Gen 1 Lithium Ion Batteries

    SciTech Connect (OSTI)

    Wright, Randy Ben; Motloch, Chester George

    2001-03-01

    This report presents the test results of a special calendar-life test conducted on 18650-size, prototype, lithium-ion battery cells developed to establish a baseline chemistry and performance for the Advanced Technology Development Program. As part of electrical performance testing, a new calendar-life test protocol was used. The test consisted of a once-per-day discharge and charge pulse designed to have minimal impact on the cell yet establish the performance of the cell over a period of time such that the calendar life of the cell could be determined. The calendar life test matrix included two states of charge (i.e., 60 and 80%) and four temperatures (40, 50, 60, and 70°C). Discharge and regen resistances were calculated from the test data. Results indicate that both discharge and regen resistance increased nonlinearly as a function of the test time. The magnitude of the discharge and regen resistance depended on the temperature and state of charge at which the test was conducted. The calculated discharge and regen resistances were then used to develop empirical models that may be useful to predict the calendar life or the cells.

  5. Cycle Life Studies of Advanced Technology Development Program Gen 1 Lithium Ion Batteries

    SciTech Connect (OSTI)

    Wright, Randy Ben; Motloch, Chester George

    2001-03-01

    This report presents the test results of a special calendar-life test conducted on 18650-size, prototype, lithium-ion battery cells developed to establish a baseline chemistry and performance for the Advanced Technology Development Program. As part of electrical performance testing, a new calendar-life test protocol was used. The test consisted of a once-per-day discharge and charge pulse designed to have minimal impact on the cell yet establish the performance of the cell over a period of time such that the calendar life of the cell could be determined. The calendar life test matrix included two states of charge (i.e., 60 and 80%) and four temperatures (40, 50, 60, and 70°C). Discharge and regen resistances were calculated from the test data. Results indicate that both discharge and regen resistance increased nonlinearly as a function of the test time. The magnitude of the discharge and regen resistance depended on the temperature and state of charge at which the test was conducted. The calculated discharge and regen resistances were then used to develop empirical models that may be useful to predict the calendar life or the cells.

  6. Development and Applications of Photosensitive Device Systems to Studies of Biological and Organic Materials

    SciTech Connect (OSTI)

    Gruner, Sol M.

    2005-06-01

    R&D and application testing are proceeding on Pixel Array Detectors (PADs) for time-resolved and crystallographic applications at synchrotron radiation (SR) sources [1, 2, 4, 23, 24]. In conjunction with an NIH-funded SBIR grant, a novel mixed-mode analog/digital pixel design is being developed. Reports and publications on recent developments in the hybrid detector will be presented at the IEEE Nuclear Science Symposium in Rome in October, 2004 [21-23]. We've been invited to help prepare a special issue of Journal of Synchrotron Radiation on x-ray detectors; additionally, we will contribute an article on fast time-resolved PADs [24]. Application of a PAD developed under a DOE Facilities Initiative Grant, in collaboration with Dr. Jin Wang's group at the Advanced Photon Source, is being intensively used for microsecond time-resolved x-ray imaging of fuel injectors [3, 15]. This detector is the primary data acquisition device used by the Wang collaboration for work which was awarded the 2002 DOE Combustion and Emission Control R&D award.

  7. An integrated experimental and numerical study: Developing a reaction transport model that couples chemical reactions of mineral dissolution/precipitation with spatial and temporal flow variations in CO2/brine/rock systems

    Broader source: Energy.gov [DOE]

    Project objectives: Generate and characterize mineral dissolution/precipitation reactions in supercritical CO2/brine/rock systems under pressure-temperature-chemistry conditions resembling CO2injection into EGS. Characterize three-dimensional spatial and temporal distributions of rock structures subject to mineral dissolution/precipitation processes by X-ray tomography, SEM imaging, and Microprobe analysis.

  8. Numerical Modeling At Dixie Valley Geothermal Area (McKenna ...

    Open Energy Info (EERE)

    Numerical Modeling At Dixie Valley Geothermal Area (McKenna & Blackwell, 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Numerical Modeling...

  9. Numerical Verification of Bounce Harmonic Resonances in Neoclassical

    Office of Scientific and Technical Information (OSTI)

    for Tokamaks Kimin Kim, Jong-Kyu Park and Allen H. Boozer 70 PLASMA PHYSICS AND FUSION TECHNOLOGY Tokamaks, Numerical Verification Tokamaks, Numerical Verification This...

  10. Toward portable programming of numerical linear algebra on manycore...

    Office of Scientific and Technical Information (OSTI)

    Toward portable programming of numerical linear algebra on manycore nodes. Citation Details In-Document Search Title: Toward portable programming of numerical linear algebra on ...

  11. Numerical Simulation of Injectivity Effects of Mineral Scaling...

    Office of Scientific and Technical Information (OSTI)

    Numerical Simulation of Injectivity Effects of Mineral Scaling and Clay Swelling in a Fractured Geothermal Reservoir Citation Details In-Document Search Title: Numerical Simulation ...

  12. Sandia Energy - Numerical Simulations of Hydrokinetics in the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Numerical Simulations of Hydrokinetics in the Roza Canal, Yakima Washington Home Renewable Energy Energy Water Power Computational Modeling & Simulation Numerical Simulations of...

  13. Numerical modeling of water injection into vapor-dominatedgeothermal...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Numerical modeling of water injection into vapor-dominatedgeothermal reservoirs Citation Details In-Document Search Title: Numerical modeling of water injection ...

  14. ASSIMILATION OF DOPPLER RADAR DATA INTO NUMERICAL WEATHER MODELS

    SciTech Connect (OSTI)

    Chiswell, S.; Buckley, R.

    2009-01-15

    During the year 2008, the United States National Weather Service (NWS) completed an eight fold increase in sampling capability for weather radars to 250 m resolution. This increase is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current NWS operational model domains utilize grid spacing an order of magnitude larger than the radar data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of radar reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution was investigated under a Laboratory Directed Research and Development (LDRD) 'quick hit' grant to determine the impact of improved data resolution on model predictions with specific initial proof of concept application to daily Savannah River Site operations and emergency response. Development of software to process NWS radar reflectivity and radial velocity data was undertaken for assimilation of observations into numerical models. Data values within the radar data volume undergo automated quality control (QC) analysis routines developed in support of this project to eliminate empty/missing data points, decrease anomalous propagation values, and determine error thresholds by utilizing the calculated variances among data values. The Weather Research and Forecasting model (WRF) three dimensional variational data assimilation package (WRF-3DVAR) was used to incorporate the QC'ed radar data into input and boundary conditions. The lack of observational data in the vicinity of SRS available to NWS operational models signifies an important data void where radar observations can provide significant input. These observations greatly enhance the knowledge of storm structures and the environmental conditions which influence their development. As the increase in computational power and availability has made higher resolution real-time model simulations possible, the need to obtain observations to both initialize numerical models and verify their output has become increasingly important. The assimilation of high resolution radar observations therefore provides a vital component in the development and utility of numerical model forecasts for both weather forecasting and contaminant transport, including future opportunities to improve wet deposition computations explicitly.

  15. Numerical simulation of the hydrodynamical combustion to strange quark matter

    SciTech Connect (OSTI)

    Niebergal, Brian; Ouyed, Rachid; Jaikumar, Prashanth

    2010-12-15

    We present results from a numerical solution to the burning of neutron matter inside a cold neutron star into stable u,d,s quark matter. Our method solves hydrodynamical flow equations in one dimension with neutrino emission from weak equilibrating reactions, and strange quark diffusion across the burning front. We also include entropy change from heat released in forming the stable quark phase. Our numerical results suggest burning front laminar speeds of 0.002-0.04 times the speed of light, much faster than previous estimates derived using only a reactive-diffusive description. Analytic solutions to hydrodynamical jump conditions with a temperature-dependent equation of state agree very well with our numerical findings for fluid velocities. The most important effect of neutrino cooling is that the conversion front stalls at lower density (below {approx_equal}2 times saturation density). In a two-dimensional setting, such rapid speeds and neutrino cooling may allow for a flame wrinkle instability to develop, possibly leading to detonation.

  16. DOE Zero Energy Ready Home Case Study: Dwell Development, Seattle, Washington

    SciTech Connect (OSTI)

    none,

    2013-09-01

    This Challenge Home is one of 42 homes in a micro-community of ultra-modern, energy-efficient homes built by Dwell Development on an urban gray-field site in South Seattle. Every home will achieve a 5-Star Built Green rating from the regional master builders association and meet the criteria of the Northwest ENERGY STAR program, which is more strict than the national ENERGY STAR criteria. Also, the home won a 2013 Housing Innovation Award in the "systems builder" category.

  17. Liquid phase methanol LaPorte process development unit: Modification operation, and support studies

    SciTech Connect (OSTI)

    Not Available

    1991-01-28

    In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.

  18. DOE Zero Energy Ready Home Case Study: Weiss Building & Development LLC.,

    Energy Savers [EERE]

    Glendale, AZ | Department of Energy Vision Hill Lot 1, Glendale, AZ DOE Zero Energy Ready Home Case Study: Mandalay Homes, Vision Hill Lot 1, Glendale, AZ Case study of a DOE 2015 Housing Innovation Award winning production home in the hot-dry climate that got a HERS 52 without PV, or HERS -2 with PV, with 2x6 16" on center walls with R-14 ocsf plus R-4 rigid exterior; slab on grade with R-8 slab edge; sealed attic with R-31 ocsf under roof deck; 92 AFUE furnace, 15 SEER AC, 100% LED.

  19. Numerical Modeling Studies of The Dissolution-Diffusion-Convection...

    Office of Scientific and Technical Information (OSTI)

    Over time, an increasing fraction of CO2 may dissolve in the aqueous phase, and eventually some of the aqueous CO2 may react with rock minerals to form poorly soluble carbonates. ...

  20. Experimental and numerical study of the effective thermal conductivity...

    Office of Scientific and Technical Information (OSTI)

    The thermal interface resistance at the macro scale is mainly described by the physical gap between two interfaces and constriction resistance due to this gap. The small gaps ...

  1. 3-D seismic data for field development: Landslide field case study

    SciTech Connect (OSTI)

    Raeuchle, S.K.; Carr, T.R.; Tucker, R.D. )

    1990-05-01

    The Landslide field is located on the extreme southern flank of the San Joaquin basin, approximately 25 mi south of Bakersfield, California. The field, discovered in 1985, has produced in excess 9 million bbl of oil with an estimated ultimate recovery of more than 13 MMBO. The Miocene Stevens sands, which form the reservoir units at Landslide field, are interpreted as a series of constructional submarine fan deposits. Deposition of the fans was controlled by paleotopography with an abrupt updip pinch-out of the sands to the southwest. The three-dimensional seismic data over the field was used to locate the bottom hole of the landslide 22X-30 development well as close to this abrupt updip pinchout as possible in order to maximize oil recovery. A location was selected two traces (330 ft) from the updip pinch-out as mapped on the seismic data. The well was successfully drilled during 1989, encountering 150 ft of net sand with initial production in excess of 1,500 bbl of oil/day. A pressure buildup test indicates the presence of a boundary approximately 200 ft from the well bore. This boundary is interpreted as the updip pinchout of the Stevens sands against the paleohigh. Based on examination of changes in amplitude, the absence or presence of reservoir-quality sand can be mapped across the paleohighs. Application of three-dimensional seismic data, integration with well data, and in particular reconstruction cuts tied closely to existing wells can be used to map the ultimate extent of the field and contribute to efficient development.

  2. Puget Sound Dissolved Oxygen Modeling Study: Development of an Intermediate Scale Water Quality Model

    SciTech Connect (OSTI)

    Khangaonkar, Tarang; Sackmann, Brandon S.; Long, Wen; Mohamedali, Teizeen; Roberts, Mindy

    2012-10-01

    The Salish Sea, including Puget Sound, is a large estuarine system bounded by over seven thousand miles of complex shorelines, consists of several subbasins and many large inlets with distinct properties of their own. Pacific Ocean water enters Puget Sound through the Strait of Juan de Fuca at depth over the Admiralty Inlet sill. Ocean water mixed with freshwater discharges from runoff, rivers, and wastewater outfalls exits Puget Sound through the brackish surface outflow layer. Nutrient pollution is considered one of the largest threats to Puget Sound. There is considerable interest in understanding the effect of nutrient loads on the water quality and ecological health of Puget Sound in particular and the Salish Sea as a whole. The Washington State Department of Ecology (Ecology) contracted with Pacific Northwest National Laboratory (PNNL) to develop a coupled hydrodynamic and water quality model. The water quality model simulates algae growth, dissolved oxygen, (DO) and nutrient dynamics in Puget Sound to inform potential Puget Sound-wide nutrient management strategies. Specifically, the project is expected to help determine 1) if current and potential future nitrogen loadings from point and non-point sources are significantly impairing water quality at a large scale and 2) what level of nutrient reductions are necessary to reduce or control human impacts to DO levels in the sensitive areas. The project did not include any additional data collection but instead relied on currently available information. This report describes model development effort conducted during the period 2009 to 2012 under a U.S. Environmental Protection Agency (EPA) cooperative agreement with PNNL, Ecology, and the University of Washington awarded under the National Estuary Program

  3. Numerical routines for predicting ignition in pyrotechnic devices

    SciTech Connect (OSTI)

    Pierce, K.G.

    1986-06-01

    Two numerical models of the thermal processes leading to ignition in a pyrotechnic device have been developed. These models are based on finite difference approximations to the heat diffusion equation, with temperature-dependent thermal properties, in a single spatial coordinate. The derivation of the finite difference equations is discussed and the methods employed at boundaries and interfaces are given. The sources of the thermal-properties data are identified and how these data are used is explained. The program structure is explained and example runs of the programs are given.

  4. DOE ZERH Case Study: United Way of Long Island Housing Development Corporation, Patchogue, NY

    SciTech Connect (OSTI)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning affordable home in the mixed-humid climate that got HERS 40 without PV, -3 with PV, with 2x4 16: on center walls with R-13.5 dense packed cellulose and 1.5” polyiso rigid; basement with 2.5: polyiso on interior; unvented attic with R-48 ocsf under roof deck; ERV tied to wall hung boiler with hydro coil.

  5. Theoretical and Computational Studies of Rare Earth Substitutes: A Test-bed for Accelerated Materials Development

    SciTech Connect (OSTI)

    Benedict, Lorin X.

    2015-10-26

    Hard permanent magnets in wide use typically involve expensive Rare Earth elements. In this effort, we investigated candidate permanent magnet materials which contain no Rare Earths, while simultaneously exploring improvements in theoretical methodology which enable the better prediction of magnetic properties relevant for the future design and optimization of permanent magnets. This included a detailed study of magnetocrystalline anisotropy energies, and the use of advanced simulation tools to better describe magnetic properties at elevated temperatures.

  6. Numerical modeling of pulsed laser-material interaction and of laser plume dynamics

    SciTech Connect (OSTI)

    Zhao, Qiang; Shi, Yina

    2015-03-10

    We have developed two-dimensional Arbitrary Lagrangian Eulerian (ALE) code which is used to study the physical processes, the plasma absorption, the crater profile, and the temperature distribution on metallic target and below the surface. The ALE method overcomes problems with Lagrangian moving mesh distortion by mesh smoothing and conservative quantities remapping from Lagrangian mesh to smoothed one. A new second order accurate diffusion solver has been implemented for the thermal conduction and radiation transport on distorted mesh. The results of numerical simulation of pulsed laser ablation are presented. The influences of different processes, such as time evolution of the surface temperature, interspecies interactions (elastic collisions, recombination-dissociation reaction), interaction with an ambient gas are examined. The study presents particular interest for the analysis of experimental results obtained during pulsed laser ablation.

  7. Numerical analysis for finite-range multitype stochastic contact financial market dynamic systems

    SciTech Connect (OSTI)

    Yang, Ge; Wang, Jun; Fang, Wen

    2015-04-15

    In an attempt to reproduce and study the dynamics of financial markets, a random agent-based financial price model is developed and investigated by the finite-range multitype contact dynamic system, in which the interaction and dispersal of different types of investment attitudes in a stock market are imitated by viruses spreading. With different parameters of birth rates and finite-range, the normalized return series are simulated by Monte Carlo simulation method and numerical studied by power-law distribution analysis and autocorrelation analysis. To better understand the nonlinear dynamics of the return series, a q-order autocorrelation function and a multi-autocorrelation function are also defined in this work. The comparisons of statistical behaviors of return series from the agent-based model and the daily historical market returns of Shanghai Composite Index and Shenzhen Component Index indicate that the proposed model is a reasonable qualitative explanation for the price formation process of stock market systems.

  8. Characterize and explore potential sites and prepare research and development plan (site investigation study). Final draft. Task 2. Milestone report

    SciTech Connect (OSTI)

    1980-12-01

    A specific research and development plan to investigate the behavior and suitability of aquifers as compressed air energy storage (CAES) sites is presented. The proposed effort will evaluate present uncertainties in the performance of the underground energy storage subsystem and its impact on above ground plant design and cost. The project is planned to provide the utility industry with a quantitative basis for confidence that financial commitment to a demonstration plant and subsequent expansion is justified and poses acceptable risks. Activities in Phase II of a 5-phase overall CAES development program are reported. Information is included on the development of field testing specifications and schedules; selection of specific site for the conceptual design; development plan and schedule for the media site; development of analytical models of aquifer airflow; and well drilling requirements. As a result of these studies 14 sites in Illinois and Indiana were evaluated, 7 were ranked for suitability for CAES, and 4 were selected for possible use in the field testing program. Test procedures, the mathematical models and drilling requirments were developed. (LCL)

  9. Development of U-Frame Bending System for Studying the Vibration Integrity of Spent Nuclear Fuel

    SciTech Connect (OSTI)

    Wang, Hong; Wang, Jy-An John; Tan, Ting; Jiang, Hao; Cox, Thomas S; Howard, Rob L; Bevard, Bruce Balkcom; Flanagan, Michelle E

    2013-01-01

    A bending fatigue system developed to evaluate the response of spent nuclear fuel rods to vibration loads is presented. Design and analysis, fabrication, modification, calibration, and instrumentation are described. The system is composed of a U-frame testing setup for imposing bending loads on the spent fuel rod test specimen and a method for measuring the curvature of the rod during bending. The U-frame setup consists of two rigid arms, linking members, and linkages to a universal testing machine. The test specimen s curvature of bending is obtained through a three-point deflection measurement method consisting of three LVDTs mounted to the side connecting plates of the U-frame to capture the deformation of the test specimen. The system has some unique features: 1) The test specimen is installed by simple insertion using linear bearings incorporated with rigid sleeves. 2) Reverse cyclic bending tests can be carried out effectively and efficiently by push and pull at the loading point of the setup. Any test machine with a linear motion function can be used to drive the setup. 3) The embedded and preloaded linear roller bearings eliminate the backlash that exists in the conventional reverse bend tests. 4) The number of linkages between the U-frame and the universal machine is minimized. Namely, there are only two linkages needed at the two loading points of a U-frame setup, whereas a conventional four/three-point bend test frame requires four linkages. 5) The curvature measurement is immune to the effects arising from compliant layers and the rigid body motion of the machine. The compliant layers are used at the holding areas of the specimen to prevent contact damage. The tests using surrogate specimens composed of SS cladding/tube revealed several important phenomena that may cast light on the expected response of a spent fuel rod: 1) Cyclic quasi-static load (10 N/s under force control) in compressive mode (with respect to that at the loading point of the U-frame) produced increased irreversible or plastic curvature and also increased flexural rigidity of the surrogate rod. 2) Dynamic cyclic load (at least 1 Hz) in compressive mode resulted in increased flexural rigidity of the surrogate rod prior to SS cladding fracture. 3) Pellets and epoxy bonding exhibited various effects on the response of surrogate rods during the loading process as validated from static tests. 4) Dynamic cyclic load (2 Hz) in reverse mode demonstrated a substantial cyclic softening before the fracture of the surrogate rod. The degree of decrease in flexural rigidity was consistent in both measurement and on-line monitoring. The developed U-frame system is thus verified and demonstrated to be ready for further pursuit in hot-cell tests.

  10. Low-rank coal study : national needs for resource development. Volume 2. Resource characterization

    SciTech Connect (OSTI)

    Not Available

    1980-11-01

    Comprehensive data are presented on the quantity, quality, and distribution of low-rank coal (subbituminous and lignite) deposits in the United States. The major lignite-bearing areas are the Fort Union Region and the Gulf Lignite Region, with the predominant strippable reserves being in the states of North Dakota, Montana, and Texas. The largest subbituminous coal deposits are in the Powder River Region of Montana and Wyoming, The San Juan Basin of New Mexico, and in Northern Alaska. For each of the low-rank coal-bearing regions, descriptions are provided of the geology; strippable reserves; active and planned mines; classification of identified resources by depth, seam thickness, sulfur content, and ash content; overburden characteristics; aquifers; and coal properties and characteristics. Low-rank coals are distinguished from bituminous coals by unique chemical and physical properties that affect their behavior in extraction, utilization, or conversion processes. The most characteristic properties of the organic fraction of low-rank coals are the high inherent moisture and oxygen contents, and the correspondingly low heating value. Mineral matter (ash) contents and compositions of all coals are highly variable; however, low-rank coals tend to have a higher proportion of the alkali components CaO, MgO, and Na/sub 2/O. About 90% of the reserve base of US low-rank coal has less than one percent sulfur. Water resources in the major low-rank coal-bearing regions tend to have highly seasonal availabilities. Some areas appear to have ample water resources to support major new coal projects; in other areas such as Texas, water supplies may be constraining factor on development.

  11. Study of metal dusting phenomenon and development of materials resistant to metal dusting.

    SciTech Connect (OSTI)

    Natesan, K.

    2002-03-13

    The deposition of carbon from carbonaceous gaseous environments is prevalent in many chemical and petrochemical processes such as reforming systems, syngas production systems, iron reduction plants, and others. One of the major consequences of carbon deposition is the degradation of structural materials by a phenomenon known as metal dusting. There are two major issues of importance in metal dusting. First is formation of carbon and subsequent deposition of carbon on metallic materials. Second is the initiation of metal dusting degradation of the alloy. Details are presented on a research program that is underway at Argonne National Laboratory to study the metal dusting phenomenon from a fundamental scientific base involving laboratory research in simulated process conditions and field testing of materials in actual process environments. The project has participation from the US chemical industry, alloy manufacturers, and the Materials Technology Institute, which serves the chemical process industry.

  12. Numerical modeling of the SNS H{sup ?} ion source

    SciTech Connect (OSTI)

    Veitzer, Seth A.; Beckwith, Kristian R. C.; Kundrapu, Madhusudhan; Stoltz, Peter H.

    2015-04-08

    Ion source rf antennas that produce H- ions can fail when plasma heating causes ablation of the insulating coating due to small structural defects such as cracks. Reducing antenna failures that reduce the operating capabilities of the Spallation Neutron Source (SNS) accelerator is one of the top priorities of the SNS H- Source Program at ORNL. Numerical modeling of ion sources can provide techniques for optimizing design in order to reduce antenna failures. There are a number of difficulties in developing accurate models of rf inductive plasmas. First, a large range of spatial and temporal scales must be resolved in order to accurately capture the physics of plasma motion, including the Debye length, rf frequencies on the order of tens of MHz, simulation time scales of many hundreds of rf periods, large device sizes on tens of cm, and ion motions that are thousands of times slower than electrons. This results in large simulation domains with many computational cells for solving plasma and electromagnetic equations, short time steps, and long-duration simulations. In order to reduce the computational requirements, one can develop implicit models for both fields and particle motions (e.g. divergence-preserving ADI methods), various electrostatic models, or magnetohydrodynamic models. We have performed simulations using all three of these methods and have found that fluid models have the greatest potential for giving accurate solutions while still being fast enough to perform long timescale simulations in a reasonable amount of time. We have implemented a number of fluid models with electromagnetics using the simulation tool USim and applied them to modeling the SNS H- ion source. We found that a reduced, single-fluid MHD model with an imposed magnetic field due to the rf antenna current and the confining multi-cusp field generated increased bulk plasma velocities of > 200 m/s in the region of the antenna where ablation is often observed in the SNS source. We report here on comparisons of simulated plasma parameters and code performance using more accurate physical models, such as two-temperature extended MHD models, for both a related benchmark system describing a inductively coupled plasma reactor, and for the SNS ion source. We also present results from scaling studies for mesh generation and solvers in the USim simulation code.

  13. A Study on a Tritium Separation Process Using Self-Developing Gas Chromatography with Pd-Pt Alloy

    SciTech Connect (OSTI)

    Kojima, S.; Yokosawa, M.; Matsuyama, M.; Numata, M.; Kato, T.; Watanabe, K.

    2005-07-15

    To study the practical application of a tritium separation process using Self-Developing Gas Chromatography (SDGC) using a Pd-Pt alloy, intermediate scale-up experiments (22 mm ID x 2 m length column) and the development of a computational simulation method have been conducted. In addition, intermediate scale production of Pd-Pt powder has been developed for the scale-up experiments.The following results were obtained: (1) a 50-fold scale-up from 3 mm to 22 mm causes no significant impact on the SDGC process; (2) the Pd-Pt alloy powder is applicable to a large size SDGC process; and (3) the simulation enables preparation of a conceptual design of a SDGC process for tritium separation.

  14. Developing a master plan for hospital solid waste management: A case study

    SciTech Connect (OSTI)

    Karamouz, Mohammad Zahraie, Banafsheh Kerachian, Reza Jaafarzadeh, Nemat Mahjouri, Najmeh

    2007-07-01

    Disposal of about 1750 tons of solid wastes per day is the result of a rapid population growth in the province of Khuzestan in the south west of Iran. Most of these wastes, especially hospital solid wastes which have contributed to the pollution of the environment in the study area, are not properly managed considering environmental standards and regulations. In this paper, the framework of a master plan for managing hospital solid wastes is proposed considering different criteria which are usually used for evaluating the pollution of hospital solid waste loads. The effectiveness of the management schemes is also evaluated. In order to rank the hospitals and determine the share of each hospital in the total hospital solid waste pollution load, a multiple criteria decision making technique, namely analytical hierarchy process (AHP), is used. A set of projects are proposed for solid waste pollution control and reduction in the proposed framework. It is partially applied for hospital solid waste management in the province of Khuzestan, Iran. The results have shown that the hospitals located near the capital city of the province, Ahvaz, produce more than 43% of the total hospital solid waste pollution load of the province. The results have also shown the importance of improving management techniques rather than building new facilities. The proposed methodology is used to formulate a master plan for hospital solid waste management.

  15. Advanced Numerical Model for Irradiated Concrete

    SciTech Connect (OSTI)

    Giorla, Alain B.

    2015-03-01

    In this report, we establish a numerical model for concrete exposed to irradiation to address these three critical points. The model accounts for creep in the cement paste and its coupling with damage, temperature and relative humidity. The shift in failure mode with the loading rate is also properly represented. The numerical model for creep has been validated and calibrated against different experiments in the literature [Wittmann, 1970, Le Roy, 1995]. Results from a simplified model are shown to showcase the ability of numerical homogenization to simulate irradiation effects in concrete. In future works, the complete model will be applied to the analysis of the irradiation experiments of Elleuch et al. [1972] and Kelly et al. [1969]. This requires a careful examination of the experimental environmental conditions as in both cases certain critical information are missing, including the relative humidity history. A sensitivity analysis will be conducted to provide lower and upper bounds of the concrete expansion under irradiation, and check if the scatter in the simulated results matches the one found in experiments. The numerical and experimental results will be compared in terms of expansion and loss of mechanical stiffness and strength. Both effects should be captured accordingly by the model to validate it. Once the model has been validated on these two experiments, it can be applied to simulate concrete from nuclear power plants. To do so, the materials used in these concrete must be as well characterized as possible. The main parameters required are the mechanical properties of each constituent in the concrete (aggregates, cement paste), namely the elastic modulus, the creep properties, the tensile and compressive strength, the thermal expansion coefficient, and the drying shrinkage. These can be either measured experimentally, estimated from the initial composition in the case of cement paste, or back-calculated from mechanical tests on concrete. If some are unknown, a sensitivity analysis must be carried out to provide lower and upper bounds of the material behaviour. Finally, the model can be used as a basis to formulate a macroscopic material model for concrete subject to irradiation, which later can be used in structural analyses to estimate the structural impact of irradiation on nuclear power plants.

  16. Selection of a numerical unsaturated flow code for tilted capillary barrier performance evaluation

    SciTech Connect (OSTI)

    Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States). Geohydrology Dept.

    1996-09-01

    Capillary barriers consisting of tilted fine-over-coarse layers have been suggested as landfill covers as a means to divert water infiltration away from sensitive underground regions under unsaturated flow conditions, especially for arid and semi-arid regions. Typically, the HELP code is used to evaluate landfill cover performance and design. Unfortunately, due to its simplified treatment of unsaturated flow and its essentially one-dimensional nature, HELP is not adequate to treat the complex multidimensional unsaturated flow processes occurring in a tilted capillary barrier. In order to develop the necessary mechanistic code for the performance evaluation of tilted capillary barriers, an efficient and comprehensive unsaturated flow code needs to be selected for further use and modification. The present study evaluates a number of candidate mechanistic unsaturated flow codes for application to tilted capillary barriers. Factors considered included unsaturated flow modeling, inclusion of evapotranspiration, nodalization flexibility, ease of modification, and numerical efficiency. A number of unsaturated flow codes are available for use with different features and assumptions. The codes chosen for this evaluation are TOUGH2, FEHM, and SWMS{_}2D. All three codes chosen for this evaluation successfully simulated the capillary barrier problem chosen for the code comparison, although FEHM used a reduced grid. The numerical results are a strong function of the numerical weighting scheme. For the same weighting scheme, similar results were obtained from the various codes. Based on the CPU time of the various codes and the code capabilities, the TOUGH2 code has been selected as the appropriate code for tilted capillary barrier performance evaluation, possibly in conjunction with the infiltration, runoff, and evapotranspiration models of HELP. 44 refs.

  17. Numerical uncertainty in computational engineering and physics

    SciTech Connect (OSTI)

    Hemez, Francois M

    2009-01-01

    Obtaining a solution that approximates ordinary or partial differential equations on a computational mesh or grid does not necessarily mean that the solution is accurate or even 'correct'. Unfortunately assessing the quality of discrete solutions by questioning the role played by spatial and temporal discretizations generally comes as a distant third to test-analysis comparison and model calibration. This publication is contributed to raise awareness of the fact that discrete solutions introduce numerical uncertainty. This uncertainty may, in some cases, overwhelm in complexity and magnitude other sources of uncertainty that include experimental variability, parametric uncertainty and modeling assumptions. The concepts of consistency, convergence and truncation error are overviewed to explain the articulation between the exact solution of continuous equations, the solution of modified equations and discrete solutions computed by a code. The current state-of-the-practice of code and solution verification activities is discussed. An example in the discipline of hydro-dynamics illustrates the significant effect that meshing can have on the quality of code predictions. A simple method is proposed to derive bounds of solution uncertainty in cases where the exact solution of the continuous equations, or its modified equations, is unknown. It is argued that numerical uncertainty originating from mesh discretization should always be quantified and accounted for in the overall uncertainty 'budget' that supports decision-making for applications in computational physics and engineering.

  18. Benchmark of numerical tools simulating beam propagation and secondary particles in ITER NBI

    SciTech Connect (OSTI)

    Sartori, E. Veltri, P.; Serianni, G.; Dlougach, E.; Hemsworth, R.; Singh, M.

    2015-04-08

    Injection of high energy beams of neutral particles is a method for plasma heating in fusion devices. The ITER injector, and its prototype MITICA (Megavolt ITER Injector and Concept Advancement), are large extrapolations from existing devices: therefore numerical modeling is needed to set thermo-mechanical requirements for all beam-facing components. As the power and charge deposition originates from several sources (primary beam, co-accelerated electrons, and secondary production by beam-gas, beam-surface, and electron-surface interaction), the beam propagation along the beam line is simulated by comprehensive 3D models. This paper presents a comparative study between two codes: BTR has been used for several years in the design of the ITER HNB/DNB components; SAMANTHA code was independently developed and includes additional phenomena, such as secondary particles generated by collision of beam particles with the background gas. The code comparison is valuable in the perspective of the upcoming experimental operations, in order to prepare a reliable numerical support to the interpretation of experimental measurements in the beam test facilities. The power density map calculated on the Electrostatic Residual Ion Dump (ERID) is the chosen benchmark, as it depends on the electric and magnetic fields as well as on the evolution of the beam species via interaction with the gas. Finally the paper shows additional results provided by SAMANTHA, like the secondary electrons produced by volume processes accelerated by the ERID fringe-field towards the Cryopumps.

  19. Direct numerical simulation of shear localization and decomposition reactions in shock-loaded HMX crystal

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Austin, Ryan A.; Barton, Nathan R.; Reaugh, John E.; Fried, Laurence E.

    2015-05-14

    A numerical model is developed to study the shock wave ignition of HMX crystal. The model accounts for the coupling between crystal thermal/mechanical responses and chemical reactions that are driven by the temperature field. This allows for the direct numerical simulation of decomposition reactions in the hot spots formed by shock/impact loading. The model is used to simulate intragranular pore collapse under shock wave loading. In a reference case: (i) shear-enabled micro-jetting is responsible for a modest extent of reaction in the pore collapse region, and (ii) shear banding is found to be an important mode of localization. The shearmore » bands, which are filled with molten HMX, grow out of the pore collapse region and serve as potential ignition sites. The model predictions of shear banding and reactivity are found to be quite sensitive to the respective flow strengths of the solid and liquid phases. In this regard, it is shown that reasonable assumptions of liquid-HMX viscosity can lead to chemical reactions within the shear bands on a nanosecond time scale.« less

  20. The value of numerical modeling in understanding the complete load/deformation behavior of cohesive-frictional materials

    SciTech Connect (OSTI)

    Potyondy, D.O.; Fairhurst, C.E.

    1999-07-01

    The post-peak load/deformation behavior of cohesive-frictional materials is an integral part of the overall response of a specimen to compressive loading. A more comprehensive understanding of the pre- and post-peak behavior is necessary. Recent developments in numerical modeling that allow study of the overall response of a synthetic material containing discrete heterogeneities and discontinuities both at the micro (particle) scale and at the larger scale of jointed rock masses can greatly aid the interpretation and application of laboratory test results on these materials.

  1. A survey of numerical cubature over triangles

    SciTech Connect (OSTI)

    Lyness, J.N.; Cools, R.

    1993-12-31

    This survey collects together theoretical results in the area of numerical cubature over triangles and is a vehicle for a current bibliography. We treat first the theory relating to regular integrands and then the corresponding theory for singular integrands with emphasis on the ``full comer singularity.`` Within these two sections we treat successively approaches based on transforming the triangle into a square, formulas based on polynomial moment fitting, and extrapolation techniques. Within each category we quote key theoretical results without proof, and relate other results and references to these. Nearly all the references we have found may be readily placed in one of these categories. This survey is theoretical in character and does not include recent work in adaptive and automatic integration.

  2. Development of extreme ultraviolet and soft x-ray multilayer optics for scientific studies with femtosecond/attosecond sources

    SciTech Connect (OSTI)

    Aquila, Andrew Lee

    2009-05-21

    The development of multilayer optics for extreme ultraviolet (EUV) radiation has led to advancements in many areas of science and technology, including materials studies, EUV lithography, water window microscopy, plasma imaging, and orbiting solar physics imaging. Recent developments in femtosecond and attosecond EUV pulse generation from sources such as high harmonic generation lasers, combined with the elemental and chemical specificity provided by EUV radiation, are opening new opportunities to study fundamental dynamic processes in materials. Critical to these efforts is the design and fabrication of multilayer optics to transport, focus, shape and image these ultra-fast pulses This thesis describes the design, fabrication, characterization, and application of multilayer optics for EUV femtosecond and attosecond scientific studies. Multilayer mirrors for bandwidth control, pulse shaping and compression, tri-material multilayers, and multilayers for polarization control are described. Characterization of multilayer optics, including measurement of material optical constants, reflectivity of multilayer mirrors, and metrology of reflected phases of the multilayer, which is critical to maintaining pulse size and shape, were performed. Two applications of these multilayer mirrors are detailed in the thesis. In the first application, broad bandwidth multilayers were used to characterize and measure sub-100 attosecond pulses from a high harmonic generation source and was performed in collaboration with the Max-Planck institute for Quantum Optics and Ludwig- Maximilians University in Garching, Germany, with Professors Krausz and Kleineberg. In the second application, multilayer mirrors with polarization control are useful to study femtosecond spin dynamics in an ongoing collaboration with the T-REX group of Professor Parmigiani at Elettra in Trieste, Italy. As new ultrafast x-ray sources become available, for example free electron lasers, the multilayer designs described in this thesis can be extended to higher photon energies, and such designs can be used with those sources to enable new scientific studies, such as molecular bonding, phonon, and spin dynamics.

  3. An Updated Numerical Model Of The Larderello-Travale Geothermal...

    Open Energy Info (EERE)

    Numerical Model Of The Larderello-Travale Geothermal System, Italy Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: An Updated Numerical Model Of...

  4. Mathematical and Numerical Analyses of Peridynamics for Multiscale Materials Modeling

    SciTech Connect (OSTI)

    Du, Qiang

    2014-11-12

    The rational design of materials, the development of accurate and efficient material simulation algorithms, and the determination of the response of materials to environments and loads occurring in practice all require an understanding of mechanics at disparate spatial and temporal scales. The project addresses mathematical and numerical analyses for material problems for which relevant scales range from those usually treated by molecular dynamics all the way up to those most often treated by classical elasticity. The prevalent approach towards developing a multiscale material model couples two or more well known models, e.g., molecular dynamics and classical elasticity, each of which is useful at a different scale, creating a multiscale multi-model. However, the challenges behind such a coupling are formidable and largely arise because the atomistic and continuum models employ nonlocal and local models of force, respectively. The project focuses on a multiscale analysis of the peridynamics materials model. Peridynamics can be used as a transition between molecular dynamics and classical elasticity so that the difficulties encountered when directly coupling those two models are mitigated. In addition, in some situations, peridynamics can be used all by itself as a material model that accurately and efficiently captures the behavior of materials over a wide range of spatial and temporal scales. Peridynamics is well suited to these purposes because it employs a nonlocal model of force, analogous to that of molecular dynamics; furthermore, at sufficiently large length scales and assuming smooth deformation, peridynamics can be approximated by classical elasticity. The project will extend the emerging mathematical and numerical analysis of peridynamics. One goal is to develop a peridynamics-enabled multiscale multi-model that potentially provides a new and more extensive mathematical basis for coupling classical elasticity and molecular dynamics, thus enabling next generation atomistic-to-continuum multiscale simulations. In addition, a rigorous studyof nite element discretizations of peridynamics will be considered. Using the fact that peridynamics is spatially derivative free, we will also characterize the space of admissible peridynamic solutions and carry out systematic analyses of the models, in particular rigorously showing how peridynamics encompasses fracture and other failure phenomena. Additional aspects of the project include the mathematical and numerical analysis of peridynamics applied to stochastic peridynamics models. In summary, the project will make feasible mathematically consistent multiscale models for the analysis and design of advanced materials.

  5. Numerical analysis of the spatial range of the Kondo effect

    SciTech Connect (OSTI)

    Busser, C. A.; Martins, G. B.; Ribeiro, L. Costa; Vernek, E.; Anda, E. V.; Dagotto, Elbio R

    2010-01-01

    The spatial length of the Kondo screening is still a controversial issue related to Kondo physics. While renormalization-group and Bethe-Ansatz solutions have provided detailed information about the thermodynamics of magnetic impurities, they are insufficient to study the effect on the surrounding electrons, i.e., the spatial range of the correlations created by the Kondo effect between the localized magnetic moment and the conduction electrons. The objective of this work is to present a quantitative way of measuring the extension of these correlations by studying their effect directly on the local density of states (LDOS) at arbitrary distances from the impurity. The numerical techniques used, the embedded cluster approximation, the finite-U slave bosons, and numerical renormalization group, calculate the Green s functions in real space. With this information, one can calculate how the local density of states away from the impurity is modified by its presence, below and above the Kondo temperature, and then estimate the range of the disturbances in the noninteracting Fermi sea due to the Kondo effect, and how it changes with the Kondo temperature TK. The results obtained agree with results obtained through spin-spin correlations, showing that the LDOS captures the phenomenology of the Kondo cloud as well.

  6. Numerical Modeling Of Basin And Range Geothermal Systems | Open...

    Open Energy Info (EERE)

    for extensional geothermal systems that include structure, heat input, and permeability distribution have been established using numerical models. Extensional geothermal...

  7. RACORO continental boundary layer cloud investigations. Part I: Case study development and ensemble large-scale forcings

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Vogelmann, Andrew M.; Fridlind, Ann M.; Toto, Tami; Endo, Satoshi; Lin, Wuyin; Wang, Jian; Feng, Sha; Zhang, Yunyan; Turner, David D.; Liu, Yangang; et al

    2015-06-19

    Observation-based modeling case studies of continental boundary layer clouds have been developed to study cloudy boundary layers, aerosol influences upon them, and their representation in cloud- and global-scale models. Three 60-hour case study periods span the temporal evolution of cumulus, stratiform, and drizzling boundary layer cloud systems, representing mixed and transitional states rather than idealized or canonical cases. Based on in-situ measurements from the RACORO field campaign and remote-sensing observations, the cases are designed with a modular configuration to simplify use in large-eddy simulations (LES) and single-column models. Aircraft measurements of aerosol number size distribution are fit to lognormal functionsmore » for concise representation in models. Values of the aerosol hygroscopicity parameter, κ, are derived from observations to be ~0.10, which are lower than the 0.3 typical over continents and suggestive of a large aerosol organic fraction. Ensemble large-scale forcing datasets are derived from the ARM variational analysis, ECMWF forecasts, and a multi-scale data assimilation system. The forcings are assessed through comparison of measured bulk atmospheric and cloud properties to those computed in 'trial' large-eddy simulations, where more efficient run times are enabled through modest reductions in grid resolution and domain size compared to the full-sized LES grid. Simulations capture many of the general features observed, but the state-of-the-art forcings were limited at representing details of cloud onset, and tight gradients and high-resolution transients of importance. Methods for improving the initial conditions and forcings are discussed. The cases developed are available to the general modeling community for studying continental boundary clouds.« less

  8. RACORO continental boundary layer cloud investigations. Part I: Case study development and ensemble large-scale forcings

    SciTech Connect (OSTI)

    Vogelmann, Andrew M.; Fridlind, Ann M.; Toto, Tami; Endo, Satoshi; Lin, Wuyin; Wang, Jian; Feng, Sha; Zhang, Yunyan; Turner, David D.; Liu, Yangang; Li, Zhijin; Xie, Shaocheng; Ackerman, Andrew S.; Zhang, Minghua; Khairoutdinov, Marat

    2015-06-19

    Observation-based modeling case studies of continental boundary layer clouds have been developed to study cloudy boundary layers, aerosol influences upon them, and their representation in cloud- and global-scale models. Three 60-hour case study periods span the temporal evolution of cumulus, stratiform, and drizzling boundary layer cloud systems, representing mixed and transitional states rather than idealized or canonical cases. Based on in-situ measurements from the RACORO field campaign and remote-sensing observations, the cases are designed with a modular configuration to simplify use in large-eddy simulations (LES) and single-column models. Aircraft measurements of aerosol number size distribution are fit to lognormal functions for concise representation in models. Values of the aerosol hygroscopicity parameter, κ, are derived from observations to be ~0.10, which are lower than the 0.3 typical over continents and suggestive of a large aerosol organic fraction. Ensemble large-scale forcing datasets are derived from the ARM variational analysis, ECMWF forecasts, and a multi-scale data assimilation system. The forcings are assessed through comparison of measured bulk atmospheric and cloud properties to those computed in 'trial' large-eddy simulations, where more efficient run times are enabled through modest reductions in grid resolution and domain size compared to the full-sized LES grid. Simulations capture many of the general features observed, but the state-of-the-art forcings were limited at representing details of cloud onset, and tight gradients and high-resolution transients of importance. Methods for improving the initial conditions and forcings are discussed. The cases developed are available to the general modeling community for studying continental boundary clouds.

  9. Experimental And Numerical Investigation Of An Optimized Airfoil For Vertical Axis Wind Turbines

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and numerical investigation of an optimized airfoil for vertical axis wind turbines Daniele Ragni Delft University of Technology - DUWind Carlos Sim~ ao Ferreira Delft University of Technology - DUWind Matthew Barone Sandia National Laboratories ∗ The present study addresses the experimental and numerical verification of the per- formance of a new airfoil design for lift driven vertical-axis wind-turbines (VAWT). The airfoil is obtained by a genetic algorithm optimization of the objective

  10. A Numerical Comparison of Rule Ensemble Methods and Support Vector Machines

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect A Numerical Comparison of Rule Ensemble Methods and Support Vector Machines Citation Details In-Document Search Title: A Numerical Comparison of Rule Ensemble Methods and Support Vector Machines Machine or statistical learning is a growing field that encompasses many scientific problems including estimating parameters from data, identifying risk factors in health studies, image recognition, and finding clusters within datasets, to name just a few

  11. Numerical analysis of the spatial range of the Kondo effect (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Numerical analysis of the spatial range of the Kondo effect Citation Details In-Document Search Title: Numerical analysis of the spatial range of the Kondo effect The spatial length of the Kondo screening is still a controversial issue related to Kondo physics. While renormalization-group and Bethe-Ansatz solutions have provided detailed information about the thermodynamics of magnetic impurities, they are insufficient to study the effect on the surrounding

  12. Development of Alaskan gas hydrate resources

    SciTech Connect (OSTI)

    Kamath, V.A.; Sharma, G.D.; Patil, S.L.

    1991-06-01

    The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.

  13. Numerical thermalization in particle-in-cell simulations with Monte-Carlo collisions

    SciTech Connect (OSTI)

    Lai, P. Y.; Lin, T. Y.; Lin-Liu, Y. R.; Chen, S. H.

    2014-12-15

    Numerical thermalization in collisional one-dimensional (1D) electrostatic (ES) particle-in-cell (PIC) simulations was investigated. Two collision models, the pitch-angle scattering of electrons by the stationary ion background and large-angle collisions between the electrons and the neutral background, were included in the PIC simulation using Monte-Carlo methods. The numerical results show that the thermalization times in both models were considerably reduced by the additional Monte-Carlo collisions as demonstrated by comparisons with Turner's previous simulation results based on a head-on collision model [M. M. Turner, Phys. Plasmas 13, 033506 (2006)]. However, the breakdown of Dawson's scaling law in the collisional 1D ES PIC simulation is more complicated than that was observed by Turner, and the revised scaling law of the numerical thermalization time with numerical parameters are derived on the basis of the simulation results obtained in this study.

  14. The Development and Application of Reactive Transport Modeling Techniques to Study Radionuclide Migration at Yucca Mountain, NV

    SciTech Connect (OSTI)

    Viswanathan, Hari Selvi

    1999-09-01

    Yucca Mountain, Nevada has been chosen as a possible site for the first high level radioactive waste repository in the United States. As part of the site investigation studies, we need to make scientifically rigorous estimations of radionuclide migration in the event of a repository breach. Performance assessment models used to make these estimations are computationally intensive. We have developed two reactive transport modeling techniques to simulate radionuclide transport at Yucca Mountain: (1) the selective coupling approach applied to the convection-dispersion-reaction (CDR) model and (2) a reactive stream tube approach (RST). These models were designed to capture the important processes that influence radionuclide migration while being computationally efficient. The conventional method of modeling reactive transport models is to solve a coupled set of multi-dimensional partial differential equations for the relevant chemical components in the system. We have developed an iterative solution technique, denoted the selective coupling method, that represents a versatile alternative to traditional uncoupled iterative techniques and the filly coupled global implicit method. We show that selective coupling results in computational and memory savings relative to these approaches. We develop RST as an alternative to the CDR method for solving large two- or three-dimensional reactive transport simulations for cases in which one is interested in predicting the flux across a specific control plane. In the RST method, the multidimensional problem is reduced to a series of one-dimensional transport simulations along streamlines. The key assumption with RST is that mixing at the control plane approximates the transverse dispersion between streamlines. We compare the CDR and RST approaches for several scenarios that are relevant to the Yucca Mountain Project. For example, we apply the CDR and RST approaches to model an ongoing field experiment called the Unsaturated Zone Transport Test.

  15. National Geothermal Data System: Case Studies on Exploration and Development of Potential Geothermal Sites Through Distributed Data Sharing

    SciTech Connect (OSTI)

    Anderson, Arlene; Allison, Lee; Richard, Steve; Caudill-Daugherty, Christy; Patten, Kim

    2014-09-29

    The NGDS released version 1 of the system on April 30, 2014 using the US Geoscience Information Network (USGIN) as its data integration platform. NGDS supports the 2013 Open Data Policy, and as such, the launch was featured at the 2014 Energy Datapalooza. Currently, the NGDS features a comprehensive user interface for searching and accessing nearly 41,000 documents and more than 9 million data points shared by scores of data providers across the U.S. The NGDS supports distributed data sharing, permitting the data owners to maintain the raw data that is made available to the consumer. Researchers and industry have been utilizing the NGDS as a mechanism for promoting geothermal development across the country, from hydrothermal to ground source heat pump applications. Case studies in geothermal research and exploration from across the country are highlighted.

  16. Study to develop an inspection, maintenance, and repair plan for OTEC (Ocean Thermal Energy Conversion) modular experiment plants. Final report

    SciTech Connect (OSTI)

    Not Available

    1980-04-01

    The inspection, maintenance and repair (IM and R) of the Ocean Thermal Energy Conversion (OTEC) Modular Experiment Plant (Pilot Plant) have been studied in two phases: Task I and Task II. Task I phase developed IM and R identification forms, identified requirements for routine and post casualty IM and R, and categorized and outlined potential procedures to perform IM and R activities. The efforts of the Task II phase have been directed to meet the following objectives: to provide feedback to the OTEC marine systems designs to assure that such designs reflect appropriate consideration of IM and R methods and unit costs, resulting in designs with reduced life cycle costs; to include technical information concerning OTEC IM and R possibilities to NOAA/DOE; to outline a basis in which the anticipated IM and R contributions to life cycle costs can be developed for any specific OTEC plant design; to identify IM and R methods within the state-of-the-art in the offshore industry; to determine the application of potential IM and R procedures for the commercial operation of OTEC 10/40 Pilot Plant(s); and input into the US government formulation of statutory and regulatory IM and R requirements for OTEC plants.

  17. Mechanistic studies aimed at the development of single site metal alkoxide catalysts for the production of polyoxygenates from renewable resources.

    SciTech Connect (OSTI)

    Chisholm, Malcolm H.

    2015-12-15

    The work proposed herein follows on directly from the existing 3 year grant and the request for funding is for 12 months to allow completion of this work and graduation of current students supported by DOE. The three primary projects are as follows. 1.) A comparative study of the reactivity of LMg(OR) (solvent), where L= a β-diiminate or pyrromethene ligand, in the ring-opening of cyclic esters. 2.) The homopolymerization of expoxides, particularly propylene oxide and styrene oxide, and their copolymerizations with carbon dioxide or organic anhydrides to yield polycarbonates or polyesters, respectively. 3.) The development of well-defined bismuth (III) complexes for ring-opening polymerizations that are tolerant of both air and water. In each of these topics special emphasis is placed on developing a detailed mechanistic understanding of the ring-opening event and how this is modified by the employment of specific metal and ligand combinations. This document also provides a report on findings of the past grant period that are not yet in the public domain/published and shows how the proposed work will bring the original project to conclusion.

  18. EDS coal liquefaction process development. Phase V. EDS commercial plant study design update. Illinois coal. Volume 1. Main report

    SciTech Connect (OSTI)

    Epperly, W. R.

    1981-03-01

    The objectives of the Study Design Update (SDU) were to identify the technical issues facing a potential commercial-size EDS plant design; to provide a reliable basis for estimating the cost of EDS products; and to furnish research guidance to the EDS Project. The SDU consists of two distinct studies in which different processing schemes are used to produce the hydrogen and fuel gas required by the plant. These studies are referred to as the Base Case and the Market Flexibility Sensitivity Case. In the Base Case, hydrogen is generated by steam reforming of the light hydrocarbon gases produced in the plant. Fuel gas is generated by feeding the bottoms stream from the liquefaction section vacuum pipestill to a FLEXICOKING unit. In the FLEXICOKING unit reactor, the bottoms stream is converted to coke; additional liquid product is also recovered. The coke is converted to low-Btu fuel gas in the FLEXICOKING unit gasifier. In the Market Flexibility Sensitivity (MFS) Case, the bottoms stream from the vacuum pipestill is split, and about half is sent to the FLEXICOKING unit for recovery of additional liquid product and production of fuel gas. The remainder of the bottoms stream is converted to hydrogen in a Partial Oxidation Unit. Hence the MFS Case does not consume light hydrocarbon gases produced and they are available for sale. The study of these two cases has demonstrated the importance of bottoms process selection to the economics and thermal efficiency of an EDS plant. Volume 1 - Main Report has been developed to be a stand-alone document. Both the Base Case and Market Flexibility Sensitivity (MFS) Case are covered. This volume includes an overview and detailed case summaries. It also covers economics, product recovery factors, material and energy balances, cost estimates and enviromental considerations.

  19. Numerical and experimental investigation of melting with internal heat generation within cylindrical enclosures

    SciTech Connect (OSTI)

    Amber Shrivastava; Brian Williams; Ali S. Siahpush; Bruce Savage; John Crepeau

    2014-06-01

    There have been significant efforts by the heat transfer community to investigate the melting phenomenon of materials. These efforts have included the analytical development of equations to represent melting, numerical development of computer codes to assist in modeling the phenomena, and collection of experimental data. The understanding of the melting phenomenon has application in several areas of interest, for example, the melting of a Phase Change Material (PCM) used as a thermal storage medium as well as the melting of the fuel bundle in a nuclear power plant during an accident scenario. The objective of this research is two-fold. First a numerical investigation, using computational fluid dynamics (CFD), of melting with internal heat generation for a vertical cylindrical geometry is presented. Second, to the best of authors knowledge, there are very limited number of engineering experimental results available for the case of melting with Internal Heat Generation (IHG). An experiment was performed to produce such data using resistive, or Joule, heating as the IHG mechanism. The numerical results are compared against the experimental results and showed favorable correlation. Uncertainties in the numerical and experimental analysis are discussed. Based on the numerical and experimental analysis, recommendations are made for future work.

  20. Advanced turbine systems program conceptual design and product development task 5 -- market study of the gas fired ATS. Topical report

    SciTech Connect (OSTI)

    1995-05-01

    Solar Turbines Incorporated (Solar), in partnership with the Department of Energy, will develop a family of advanced gas turbine-based power systems (ATS) for widespread commercialization within the domestic and international industrial marketplace, and to the rapidly changing electric power generation industry. The objective of the jointly-funded Program is to introduce an ATS with high efficiency, and markedly reduced emissions levels, in high numbers as rapidly as possible following introduction. This Topical Report is submitted in response to the requirements outlined in Task 5 of the Department of Energy METC Contract on Advanced Combustion Systems, Contract No, DE AC21-93MC30246 (Contract), for a Market Study of the Gas Fired Advanced Turbine System. It presents a market study for the ATS proposed by Solar, and will examine both the economic and siting constraints of the ATS compared with competing systems in the various candidate markets. Also contained within this report is an examination and analysis of Solar`s ATS and its ability to compete in future utility and industrial markets, as well as factors affecting the marketability of the ATS.

  1. Force-controlled absorption in a fully-nonlinear numerical wave tank

    SciTech Connect (OSTI)

    Spinneken, Johannes Christou, Marios; Swan, Chris

    2014-09-01

    An active control methodology for the absorption of water waves in a numerical wave tank is introduced. This methodology is based upon a force-feedback technique which has previously been shown to be very effective in physical wave tanks. Unlike other methods, an a-priori knowledge of the wave conditions in the tank is not required; the absorption controller being designed to automatically respond to a wide range of wave conditions. In comparison to numerical sponge layers, effective wave absorption is achieved on the boundary, thereby minimising the spatial extent of the numerical wave tank. In contrast to the imposition of radiation conditions, the scheme is inherently capable of absorbing irregular waves. Most importantly, simultaneous generation and absorption can be achieved. This is an important advance when considering inclusion of reflective bodies within the numerical wave tank. In designing the absorption controller, an infinite impulse response filter is adopted, thereby eliminating the problem of non-causality in the controller optimisation. Two alternative controllers are considered, both implemented in a fully-nonlinear wave tank based on a multiple-flux boundary element scheme. To simplify the problem under consideration, the present analysis is limited to water waves propagating in a two-dimensional domain. The paper presents an extensive numerical validation which demonstrates the success of the method for a wide range of wave conditions including regular, focused and random waves. The numerical investigation also highlights some of the limitations of the method, particularly in simultaneously generating and absorbing large amplitude or highly-nonlinear waves. The findings of the present numerical study are directly applicable to related fields where optimum absorption is sought; these include physical wavemaking, wave power absorption and a wide range of numerical wave tank schemes.

  2. Numerical analysis and measurement in corner-fired furnace

    SciTech Connect (OSTI)

    Zhengjun, S.; Rongsheng, G.

    1999-07-01

    For several years, numerical analysis has been successfully used by Dongfang Boiler (Group) Co., Ltd. at a 200MW boiler, a 300MW boiler and so on, which were designed and made by DBC. The distribution of results is agreement each other between numerical analysis and measurement. In conclusion, it is considered that numerical analysis can be used as an important reference method in pulverized coal boiler design and test.

  3. Toward portable programming of numerical linear algebra on manycore nodes.

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Toward portable programming of numerical linear algebra on manycore nodes. Citation Details In-Document Search Title: Toward portable programming of numerical linear algebra on manycore nodes. Abstract not provided. Authors: Heroux, Michael Allen Publication Date: 2011-05-01 OSTI Identifier: 1109301 Report Number(s): SAND2011-3556C 471555 DOE Contract Number: AC04-94AL85000 Resource Type: Conference Resource Relation: Conference: Toward petaflop numerical

  4. Advanced Numerical Methods and Software Approaches for Semiconductor Device Simulation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Carey, Graham F.; Pardhanani, A. L.; Bova, S. W.

    2000-01-01

    In this article we concisely present several modern strategies that are applicable to driftdominated carrier transport in higher-order deterministic models such as the driftdiffusion, hydrodynamic, and quantum hydrodynamic systems. The approaches include extensions of “upwind” and artificial dissipation schemes, generalization of the traditional Scharfetter – Gummel approach, Petrov – Galerkin and streamline-upwind Petrov Galerkin (SUPG), “entropy” variables, transformations, least-squares mixed methods and other stabilized Galerkin schemes such as Galerkin least squares and discontinuous Galerkin schemes. The treatment is representative rather than an exhaustive review and several schemes are mentioned only briefly with appropriate reference to the literature. Some of themore » methods have been applied to the semiconductor device problem while others are still in the early stages of development for this class of applications. We have included numerical examples from our recent research tests with some of the methods. A second aspect of the work deals with algorithms that employ unstructured grids in conjunction with adaptive refinement strategies. The full benefits of such approaches have not yet been developed in this application area and we emphasize the need for further work on analysis, data structures and software to support adaptivity. Finally, we briefly consider some aspects of software frameworks. These include dial-an-operator approaches such as that used in the industrial simulator PROPHET, and object-oriented software support such as those in the SANDIA National Laboratory framework SIERRA.« less

  5. Numerical simulation of plasma heating of a composite powder particle

    SciTech Connect (OSTI)

    Demetriou, M.D.; Lavine, A.S.; Ghoniem, N.M.

    1999-07-01

    The use of fine composite powder particles (composed of a ceramic core and a metallic coating) in plasma spraying processes is desirable in developing thin film coatings that possess high abrasion as well as high fracture resistance. Quantitative knowledge of the thermal behavior of a composite particle in a plasma beam is essential in optimizing the process variables to achieve uniform melting of the coating material. In this work, a numerical model is developed to analyze the in-flight thermal behavior of a spherically symmetric WC-Co composite particle travelling in an argon arc-jet DC plasma under strongly unsteady plasma conditions. The model gives quantitative as well as qualitative information about the thermal response of the heated particle. The important features that are addressed are the temperature response of the particle; the history of the location of the melting and vaporization fronts; and the physical state of the particle at the end of its flight. For the conditions investigated, it was determined that the internal conduction resistance is negligible as compared to the net external resistance. However, the presence of the ceramic base was found to affect the transient heating process since its content in the particle composition determines the time constant of the process. Another interesting observation is that proper selection of the particle injection speed and injection location can be effective means for optimizing the heating process and achieving uniform melting of the coating material.

  6. Numerical simulation of the environmental impact of hydraulic...

    Office of Scientific and Technical Information (OSTI)

    Numerical simulation of the environmental impact of hydraulic fracturing of tightshale gas reservoirs on near-surface groundwater: Background, base cases, shallow reservoirs,...

  7. Numerical Modeling At Lightning Dock Geothermal Area (O'Brien...

    Open Energy Info (EERE)

    Basin Additional References Retrieved from "http:en.openei.orgwindex.php?titleNumericalModelingAtLightningDockGeothermalArea(O%27Brien,EtAl.,1984)&oldid762871...

  8. Info-Gap Analysis of Truncation Errors in Numerical Simulations...

    Office of Scientific and Technical Information (OSTI)

    Title: Info-Gap Analysis of Truncation Errors in Numerical Simulations. Authors: Kamm, James R. ; Witkowski, Walter R. ; Rider, William J. ; Trucano, Timothy Guy ; Ben-Haim, Yakov. ...

  9. Info-Gap Analysis of Numerical Truncation Errors. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Title: Info-Gap Analysis of Numerical Truncation Errors. Authors: Kamm, James R. ; Witkowski, Walter R. ; Rider, William J. ; Trucano, Timothy Guy ; Ben-Haim, Yakov. Publication ...

  10. History, Applications, Numerical Values and Problems with the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Numerical Values and Problems with the Calculation of EROI (Energy Return on Energy Investment) Professor Charles Hall State University of NY College of Environmental Science and...

  11. Numerical simulations for low energy nuclear reactions including...

    Office of Scientific and Technical Information (OSTI)

    Numerical simulations for low energy nuclear reactions including direct channels to ... Visit OSTI to utilize additional information resources in energy science and technology. A ...

  12. Numerical Modeling At Raft River Geothermal Area (1983) | Open...

    Open Energy Info (EERE)

    Raft River Geothermal Area (1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Numerical Modeling At Raft River Geothermal Area (1983)...

  13. Numerical simulations for low energy nuclear reactions including...

    Office of Scientific and Technical Information (OSTI)

    energy nuclear reactions including direct channels to validate statistical models Citation Details In-Document Search Title: Numerical simulations for low energy nuclear reactions ...

  14. An Iterated, Multipoint Differential Transform Method for Numerically...

    Office of Scientific and Technical Information (OSTI)

    ...Value Problems Citation Details In-Document Search Title: An Iterated, Multipoint Differential Transform Method for Numerically Evolving Partial Differential Equation Initial-Value ...

  15. Numerical Analysis of Fixed Point Algorithms in the Presence...

    Office of Scientific and Technical Information (OSTI)

    in the Presence of Hardware Faults Citation Details In-Document Search Title: Numerical Analysis of Fixed Point Algorithms in the Presence of Hardware Faults You are ...

  16. Numerical Modelling of Geothermal Systems a Short Introduction...

    Open Energy Info (EERE)

    Modelling of Geothermal Systems a Short Introduction Jump to: navigation, search OpenEI Reference LibraryAdd to library General: Numerical Modelling of Geothermal Systems a Short...

  17. Final Report on Experimental and Numerical Modeling Activities...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Final Report on Experimental and Numerical Modeling Activities for the Newark Basin Citation Details In-Document Search Title: Final Report on Experimental and ...

  18. A Numerical Evaluation Of Electromagnetic Methods In Geothermal...

    Open Energy Info (EERE)

    Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Numerical Evaluation Of Electromagnetic Methods In Geothermal Exploration - Discussion...

  19. Numerical Modeling At Coso Geothermal Area (1995) | Open Energy...

    Open Energy Info (EERE)

    transform is employed to characterize guided-wave's velocity-frequency dispersion, and numerical methods are used to simulate the guided-wave propagation. The modeling...

  20. Direct Numerical Simulations and Robust Predictions of Cloud...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cloud. Credit: Computational Science and Engineering Laboratory, ETH Zurich, Switzerland Direct Numerical Simulations and Robust Predictions of Cloud Cavitation Collapse PI Name:...

  1. A review of direct numerical simulations of astrophysical detonations and their implications

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Parete-Koon, Suzanne T.; Smith, Christopher R.; Papatheodore, Thomas L.; Bronson Messer, O. E.

    2013-04-11

    Multi-dimensional direct numerical simulations (DNS) of astrophysical detonations in degenerate matter have revealed that the nuclear burning is typically characterized by cellular structure caused by transverse instabilities in the detonation front. Type Ia supernova modelers often use one- dimensional DNS of detonations as inputs or constraints for their whole star simulations. While these one-dimensional studies are useful tools, the true nature of the detonation is multi-dimensional. The multi-dimensional structure of the burning influences the speed, stability, and the composition of the detonation and its burning products, and therefore, could have an impact on the spectra of Type Ia supernovae. Considerablemore » effort has been expended modeling Type Ia supernovae at densities above 1x107 g∙cm-3 where the complexities of turbulent burning dominate the flame propagation. However, most full star models turn the nuclear burning schemes off when the density falls below 1x107 g∙cm-3 and distributed burning begins. The deflagration to detonation transition (DDT) is believed to occur at just these densities and consequently they are the densities important for studying the properties of the subsequent detonation. In conclusion, this work reviews the status of DNS studies of detonations and their possible implications for Type Ia supernova models. It will cover the development of Detonation theory from the first simple Chapman-Jouguet (CJ) detonation models to the current models based on the time-dependent, compressible, reactive flow Euler equations of fluid dynamics.« less

  2. Numerical Cosmology: Building a Dynamical Universe

    SciTech Connect (OSTI)

    Garrison, David

    2010-10-11

    In this talk I discuss an often over-looked aspect of most cosmological models, dynamical interactions caused by gravitational waves. I begin by reviewing our current state of cosmological knowledge and gravitational waves. Then, I review work done to understand the nature of primordial magnetic fields. Finally, I combine the ideas of gravitational wave theory and plasma turbulence to develop a new theory of cosmic structure formation. Eventually, this work could help to explain the distribution of mass-energy in the observable universe as well as the anisotropies in the Cosmic Microwave Background without a heavy dependence on dark matter. This work seeks to explain how the dense, hot, turbulent plasma of protons, neutrons, electrons and neutrinos cooled in the presence of gravitational waves to form into structures and develop a statistical mechanics to describe this dynamical system.

  3. Development of the CD symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    SciTech Connect (OSTI)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Grim, G. P.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; Bleuel, D. L.; Bond, E. J.; Bradley, D. K.; Caggiano, J. A.; Callahan, D. A.; Cerjan, C. J.; Chen, K. C.; Edgell, D. H.; Edwards, M. J.; Fittinghoff, D.; Frenje, J. A.; Gatu-Johnson, M.; Glebov, V. Y.; Glenn, S.; Guler, N.; Haan, S. W.; Hamza, A.; Hatarik, R.; Herrmann, H. W.; Hoover, D.; Hsing, W. W.; Izumi, N.; Kervin, P.; Khan, S.; Kilkenny, J. D.; Kline, J.; Knauer, J.; Kyrala, G.; Landen, O. L.; Ma, T.; MacPhee, A. G.; McNaney, J. M.; Mintz, M.; Moore, A.; Nikroo, A.; Pak, A.; Parham, T.; Petrasso, R.; Rinderknecht, H. G.; Sayre, D. B.; Schneider, M.; Stoeffl, W.; Tommasini, R.; Town, R. P.; Widmann, K.; Wilson, D. C.; Yeamans, C. B.

    2014-09-09

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T₂-gas filled CH-shell implosions equipped with 4 μm thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within the CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8 μm have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly-radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.

  4. Development of the CD symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Grim, G. P.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; et al

    2014-09-09

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T₂-gas filled CH-shell implosions equipped with 4 μm thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within themore » CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8 μm have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly-radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.« less

  5. Development of the CD Symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    SciTech Connect (OSTI)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; Bleuel, D. L.; Bond, E. J.; Bradley, D. K.; Caggiano, J. A.; Callahan, D. A.; Cerjan, C. J.; Edwards, M. J.; Fittinghoff, D.; Glenn, S.; Haan, S. W.; Hamza, A.; and others

    2014-09-15

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T{sub 2}-gas filled CH-shell implosions equipped with 4 ?m thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within the CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8??m have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.

  6. Green River air quality model development: meteorological and tracer data, July/August 1982 field study in Brush Valley, Colorado

    SciTech Connect (OSTI)

    Whiteman, C.D.; Lee, R.N.; Orgill, M.M.; Zak, B.D.

    1984-06-01

    Meteorological and atmospheric tracer studies were conducted during a 3-week period in July and August of 1982 in the Brush Creek Valley of northwestern Colorado. The objective of the field experiments was to obtain data to evaluate a model, called VALMET, developed at PNL to predict dispersion of air pollutants released from an elevated stack located within a deep mountain valley in the post-sunrise temperature inversion breakup period. Three tracer experiments were conducted in the valley during the 2-week period. In these experiments, sulfur hexafluoride (SF/sub 6/) was released from a height of approximately 100 m, beginning before sunrise and continuing until the nocturnal down-valley winds reversed several hours after sunrise. Dispersion of the sulfur hexafluoride after release was evaluated by measuring SF/sub 6/ concentrations in ambient air samples taken from sampling devices operated within the valley up to about 8 km down valley from the source. An instrumented research aircraft was also used to measure concentrations in and above the valley. Tracer samples were collected using a network of radio-controlled bag sampling stations, two manually operated gas chromatographs, a continuous SF/sub 6/ monitor, and a vertical SF/sub 6/ profiler. In addition, basic meteorological data were collected during the tracer experiments. Frequent profiles of vertical wind and temperature structure were obtained with tethered balloons operated at the release site and at a site 7.7 km down the valley from the release site. 10 references, 63 figures, 50 tables.

  7. NUMERICAL VERIFICATION OF THE RELAP-7 CORE CHANNEL SINGLE-PHASE MODEL

    SciTech Connect (OSTI)

    Haihua Zhao; Ling Zou; Hongbin Zhang; Richard Martineau

    2014-06-01

    The RELAP-7 code is the next generation of nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). All the physics in RELAP-7 are fully coupled and the errors resulted from the traditional operator-splitting approach are eliminated. By using 2nd order methods in both time and space and eliminating operator-splitting errors, the numerical error of RELAP-7 can be minimized. Numerical verification is the process to verify the orders of numerical methods. It is an important part of modern verification and validation process. The core channel component in RELAP-7 is designed to simulate coolant flow as well as the conjugated heat transfer between coolant flow and the fuel rod. A special treatment at fuel centerline to avoid numerical singularity for the cylindrical heat conduction in the continuous finite element mesh is discussed. One steady state test case and one fast power up transient test case are utilized for the verification of the core channel model with single-phase flow. Analytical solution for the fuel pin temperature and figures of merit such as peak clad temperature and peak fuel temperature are used to define numerical errors. These cases prove that the mass and energy are well conserved and 2nd order convergence rates for both time and space are achieved in the core channel model.

  8. Numerical design of SiC bulk crystal growth for electronic applications

    SciTech Connect (OSTI)

    Wejrzanowski, T.; Grybczuk, M.; Kurzydlowski, K. J.; Tymicki, E.

    2014-10-06

    Presented study concerns numerical simulation of Physical Vapor Transport (PVT) growth of bulk Silicon Carbide (SiC) crystals. Silicon Carbide is a wide band gap semiconductor, with numerous applications due to its unique properties. Wider application of SiC is limited by high price and insufficient quality of the product. Those problems can be overcame by optimizing SiC production methods. Experimental optimization of SiC production is expensive because it is time consuming and requires large amounts of energy. Numerical modeling allows to learn more about conditions inside the reactor and helps to optimize the process at much lower cost. In this study several simulations of processes with different reactor geometries were presented along with discussion of reactor geometry influence on obtained monocrystal shape and size.

  9. Numerical approaches to combustion modeling. Progress in Astronautics and Aeronautics. Vol. 135

    SciTech Connect (OSTI)

    Oran, E.S.; Boris, J.P. )

    1991-01-01

    Various papers on numerical approaches to combustion modeling are presented. The topics addressed include; ab initio quantum chemistry for combustion; rate coefficient calculations for combustion modeling; numerical modeling of combustion of complex hydrocarbons; combustion kinetics and sensitivity analysis computations; reduction of chemical reaction models; length scales in laminar and turbulent flames; numerical modeling of laminar diffusion flames; laminar flames in premixed gases; spectral simulations of turbulent reacting flows; vortex simulation of reacting shear flow; combustion modeling using PDF methods. Also considered are: supersonic reacting internal flow fields; studies of detonation initiation, propagation, and quenching; numerical modeling of heterogeneous detonations, deflagration-to-detonation transition to reactive granular materials; toward a microscopic theory of detonations in energetic crystals; overview of spray modeling; liquid drop behavior in dense and dilute clusters; spray combustion in idealized configurations: parallel drop streams; comparisons of deterministic and stochastic computations of drop collisions in dense sprays; ignition and flame spread across solid fuels; numerical study of pulse combustor dynamics; mathematical modeling of enclosure fires; nuclear systems.

  10. Progress Letter Report on Bending Fatigue Test System Development for Spent Nuclear Fuel Vibration Integrity Study (Out-of-cell fatigue testing development - Task 2.4)

    SciTech Connect (OSTI)

    Wang, Jy-An John; Wang, Hong; Cox, Thomas S; Baldwin, Charles A; Bevard, Bruce Balkcom

    2013-08-01

    Vibration integrity of high burn-up spent nuclear fuel in transportation remains to be a critical component of US nuclear waste management system. The structural evaluation of package for spent fuel transportation eventually will need to see if the content or spent fuel is in a subcritical condition. However, a system for testing and characterizing such spent fuel is still lacking mainly due to the complication involved with dealing radioactive specimens in a hot cell environment. Apparently, the current state-of-the-art in spent fuel research and development is quite far away from the delivery of reliable mechanical property data for the assessment of spent fuels in the transport package evaluation. Under the sponsorship of US NRC, ORNL has taken the challenge in developing a robust testing system for spent fuel in hot cell. An extensive literature survey was carried out and unique requirements of such testing system were identified. The U-frame setup has come to the top among various designs examined for reverse bending fatigue test of spent fuel rod. The U-frame has many features that deserve mentioned here: Easy to install spent fuel rod in test; Less linkages than in conventional bending test setup such as three-point or four-point bending; Target the failure mode relevant to the fracture of spent fuel rod in transportation by focusing on pure bending; The continuous calibrations and modifications resulted in the third generation (3G) U-frame testing setup. Rigid arms are split along the LBB axis at rod sample ends. For each arm, this results in a large arm body and an end piece. Mating halves of bushings were modified into two V-shaped surfaces on which linear roller bearings (LRB) are embedded. The rod specimen is installed into the test fixture through opening and closing slide end-pieces. The 3G apparently has addressed major issues of setup identified in the previous stage and been proven to be eligible to be further pursued in this project. On the other hand, the purchase of universal testing machine or Bose dual LM2 TB was completed and the testing system was delivered to ORNL in August 2012. The preliminary confirmation of the system and on-site training were given by Bose field engineer and regional manager on 8/1-8/2/2012. The calibration of Bose testing system has been performed by ORNL because the integration of ORNL setup into the Bose TestBench occurred after the installation. Major challenge with this process arose from two aspects: 1) the load control involves two load cells, and 2) U-frame setup itself is a non-standard specimen. ORNL has been able to implement the load control through Cycle Indirect along with pinning the U-frame setup. Two meetings with ORNL hot-cell group (November 2012 and January 2013) were held to discuss the potential issues with both epoxy mounting of rigid sleeve and U-frame setup. Many suggestions were provided to make the procedure friendlier to the manipulator in hot cell. Addressing of these suggestions resulted in another cycle of modifications of both vise mold and setup. The initial meeting with ORNL I&C group occurred in November 2012 with regard to the Bose cable modification and design of central panel to integrate the cables and wires. The first round of cable modification and central panel fabrication was completed in February 2012. The testing with the modified cables exhibited substantial noises and the testing system was not shown to be stable. It was believed the cross talk was responsible to the noise, and a central panel with a better grounding and shielding was highly recommended. The central panel has been re-designed and fabricated in March 2013. In the subsequent period, the ORNL made substantial effort to debug the noises with the load cell channel, and to resolve the noises and nonlinearity with RDP LVDTs related to the integration of RDP LVDTs to Bose system. At the same time, ORNL has completed the verification tests of Bose test system, including cycle tests under reversal bending in load control, bending tests under monotonic load, and cycle tests under reversal bending in load control on MTS machine to verify the results of Bose machine. These results are shown to be consistent under equivalent loading conditions, especially for the cycle tests. Rad hardened LVDTs will be incorporated into the Bose system once received, and 10 Hz tests will be completed in the next step. The schedule for the final check of the Bose system is being finalized before the system delivered to the hot cell.

  11. Numerical Simulation of Combustion and Rotor-Stator Interaction in a Turbine Combustor

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Isvoranu, Dragos D.; Cizmas, Paul G. A.

    2003-01-01

    This article presents the development of a numerical algorithm for the computation of flow and combustion in a turbine combustor. The flow and combustion are modeled by the Reynolds-averaged Navier-Stokes equations coupled with the species-conservation equations. The chemistry model used herein is a two-step, global, finite-rate combustion model for methane and combustion gases. The governing equations are written in the strong conservation form and solved using a fully implicit, finite-difference approximation. The gas dynamics and chemistry equations are fully decoupled. A correction technique has been developed to enforce the conservation of mass fractions. The numerical algorithm developed herein has beenmore » used to investigate the flow and combustion in a one-stage turbine combustor.« less

  12. DRIVER TO SUPPORT USE OF NUMERICAL SIMULATION TOOLS

    Energy Science and Technology Software Center (OSTI)

    2001-02-13

    UNIPACK is a computer interface that simplifies and enhances the use of numerical simulation tools to design a primary geometry and/or a forming die for a powder compact and/or to design the pressing process used to shape a powder by compaction. More particularly, it is an interface that utilizes predefined generic geometric configurations to simplify the use of finite element method modeling software to simply and more efficiently design: (1) the shape and size amore » powder compact; (2) a forming die to shape a powder compact; and/or (3) the pressing process used to form a powder compact. UNIPACK is a user interface for a predictive model for powder compaction that incorporates unprecedented flexibility to design powder press tooling and powder pressing processes. UNIPACK works with the Sandia National Laboratories (SNL) Engineering Analysis Cide Access System (SEACAS) to generate a finite element (FE) mesh and automatically perform a FE analysis of powder compaction. UNIPACK was developed to allow a non-expert with minimal training to quickly and easily design/construct a variable dimension component or die in real time on a desktop or laptop personal computer.« less

  13. Comparison of numerical models of a pyrotechnic device

    SciTech Connect (OSTI)

    Pierce, K.G.

    1986-01-01

    The predictions of two numerical models of a hot-wire initiated pyrotechnic device are compared to each other and to experimental results. Both models employ finite difference approximations to the heat diffusion equation in cylindrical coordinates. The temperature dependence of the thermal properties of the pyrotechnic materials and of the bridgewire are modeled. An Arrhenius' model is used to describe the exothermic reaction in the powder. One model employs a single radial coordinate and predicts the radial temperature distribution in the bridgewire and surrounding powder mass. In addition to the radial coordinate, the other model also employs a longitudinal coordinate to predict the temperature distribution parallel to the axis of the bridgewire. The predictions of the two-dimensional model concerning the energy requirements for ignition and the energy losses from the ends of the bridgewire are presented. A comparison of the predictions of the two models and the development of thermal gradients are employed to define the regime where the assumption, in the one-dimensional model, of negligible heat transfer axial to the bridgewire does not lead to significant error. The general problems associated with predicting ignition from a diffusion model are also discussed.

  14. Advances in the numerical modeling of field-reversed configurations

    SciTech Connect (OSTI)

    Belova, Elena V.; Davidson, Ronald C.; Ji, Hantao; Yamada, Masaaki

    2006-05-15

    The field-reversed configuration (FRC) is a compact torus with little or no toroidal magnetic field. A theoretical understanding of the observed FRC equilibrium and stability properties presents significant challenges due to the high plasma beta, plasma flows, large ion gyroradius, and the stochasticity of the particle orbits. Advanced numerical simulations are generally required to describe and understand the detailed behavior of FRC plasmas. Results of such simulations are presented in this paper. It is shown that 3D nonlinear hybrid simulations using the HYM code [E. V. Belova et al., Phys. Plasmas 7, 4996 (2000)] reproduce all major experimentally observed stability properties of elongated (theta-pinch-formed) FRCs. Namely, the scaling of the growth rate of the n=1 tilt mode with the S*/E parameter (S* is the FRC kinetic parameter, E is elongation, and n is toroidal mode number), the nonlinear saturation of the tilt mode, ion toroidal spin-up, and the growth of the n=2 rotational mode have been demonstrated and studied in detail. The HYM code has also been used to study stability properties of FRCs formed by the counterhelicity spheromak merging method. A new stability regime has been found for FRCs with elongation E{approx}1, which requires a close-fitting conducting shell and energetic beam ion stabilization.

  15. Study of domestic social and economic impacts of ocean thermal energy conversion (OTEC) commercial development. Volume I. Economic impacts

    SciTech Connect (OSTI)

    1981-12-22

    This analysis identifies the economic impacts associated with OTEC development and quantifies them at the national, regional, and industry levels. It focuses on the effects on the United States' economy of the domestic development and utilization of twenty-five and fifty 400 MWe OTEC power plants by the year 2000. The methodology employed was characteristic of economic impact analysis. After conducting a literature review, a likely future OTEC scenario was developed on the basis of technological, siting, and materials requirements parameters. These parameters were used to identify the industries affected by OTEC development; an economic profile was constructed for each of these industries. These profiles established an industrial baseline from which the direct, indirect, and induced economic impacts of OTEC implementation could be estimated. Each stage of this analysis is summarized; and the economic impacts are addressed. The methodology employed in estimating the impacts is described.

  16. The development of a high-throughput gradient array apparatus for the study of porous polymer networks.

    SciTech Connect (OSTI)

    Majumdar, Partha; Lee, Elizabeth; Chisholm, Bret J.; Dirk, Shawn M.; Weisz, Michael; Bahr, James; Schiele, Kris

    2010-01-01

    A gradient array apparatus was constructed for the study of porous polymers produced using the process of chemically-induced phase separation (CIPS). The apparatus consisted of a 60 element, two-dimensional array in which a temperature gradient was placed in the y-direction and composition was varied in the x-direction. The apparatus allowed for changes in opacity of blends to be monitored as a function of temperature and cure time by taking images of the array with time. The apparatus was validated by dispense a single blend composition into all 60 wells of the array and curing them for 24 hours and doing the experiment in triplicate. Variations in micron scale phase separation were readily observed as a function of both curing time and temperature and there was very good well-to-well consistency as well as trial-to-trial consistency. Poragen of samples varying with respect to cure temperature was removed and SEM images were obtained. The results obtained showed that cure temperature had a dramatic affect on sample morphology, and combining data obtained from visual observations made during the curing process with SEM data can enable a much better understanding of the CIPS process and provide predictive capability through the relatively facile generation of composition-process-morphology relationships. Data quality could be greatly enhanced by making further improvements in the apparatus. The primary improvements contemplated include the use of a more uniform light source, an optical table, and a CCD camera with data analysis software. These improvements would enable quantification of the amount of scattered light generated from individual elements as a function of cure time. In addition to the gradient array development, porous composites were produced by incorporating metal particles into a blend of poragen, epoxy resin, and crosslinker. The variables involved in the experiment were metal particle composition, primary metal particle size, metal concentration, and poragen composition. A total of 16 different porous composites were produced and characterized using SEM. In general, the results showed that pore morphology and the distribution of metal particles was dependent on multiple factors. For example, the use of silver nanoparticles did not significantly affect pore morphology for composites derived from decanol as the poragen, but exceptionally large pores were obtained with the use of decane as the poragen. With regard to the effect of metal particle size, silver nanoparticles were essentially exclusively dispered in the polymer matrix while silver microparticles were found in pores. For nickel particles, both nanoparticles and microparticles were largely dispersed in the polymer matrix and not in the pores.

  17. Simple intrinsic defects in GaAs : numerical supplement.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2012-04-01

    This Report presents numerical tables summarizing properties of intrinsic defects in gallium arsenide, GaAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz and O.A. von Lilienfeld, 'Simple intrinsic defects in GaAs', Modelling Simul. Mater. Sci Eng., Vol. 17, 084007 (2009), and intended for use as reference tables for a defect physics package in device models. The numerical results for density functional theory calculations of properties of simple intrinsic defects in gallium arsenide are presented.

  18. Numerical and laboratory simulations of auroral acceleration

    SciTech Connect (OSTI)

    Gunell, H.; De Keyser, J.; Mann, I.

    2013-10-15

    The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

  19. Numerical simulation experiments on the long-term evolution of...

    Office of Scientific and Technical Information (OSTI)

    the long-term evolution of a CO2 plume under a sloping caprock Citation Details In-Document Search Title: Numerical simulation experiments on the long-term evolution of a CO2 plume ...

  20. A Numerical Evaluation Of Electromagnetic Methods In Geothermal...

    Open Energy Info (EERE)

    L Pellerin, J M Johnston & G W Hohmann, Geophysics, 61(1), 1996, Pp 121-130 Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Numerical...

  1. Use of ARM observations and numerical models to determine radiative...

    Office of Scientific and Technical Information (OSTI)

    We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the ...

  2. Kees Bol, a scientist on Project Matterhorn, PDX and numerous...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    a scientist on Project Matterhorn, PDX and numerous experiments, dies at 90 By Jeanne Jackson DeVoe August 25, 2015 Tweet Widget Google Plus One Share on Facebook Photo courtesy...

  3. Characterize and explore potential sites and prepare research and development plan (site investigation study). Final draft. Task 2. Milestone report

    SciTech Connect (OSTI)

    1980-12-01

    Phase II of a 5-phase overall compressed air energy storage (CAES) development program was performed to characterize and explore potential CAES sites and to prepare a research and development plan. This volume for Phase II activities contains an evaluation of the suitability of seven selected sites to undergo field drilling and air injection testing; a bibliography; results of a literature search on the effects of air injection of aquifer-caprock well systems; reservoir data for the sites; cost estimates; and predicted potential risks from a CAES plant. (LCL)

  4. Accurate Numerical Simulations Of Chemical Phenomena Involved in Energy

    Office of Scientific and Technical Information (OSTI)

    Production and Storage with MADNESS and MPQC: ALCF-2 Early Science Program Technical Report (Technical Report) | SciTech Connect Technical Report: Accurate Numerical Simulations Of Chemical Phenomena Involved in Energy Production and Storage with MADNESS and MPQC: ALCF-2 Early Science Program Technical Report Citation Details In-Document Search Title: Accurate Numerical Simulations Of Chemical Phenomena Involved in Energy Production and Storage with MADNESS and MPQC: ALCF-2 Early Science

  5. An Iterated, Multipoint Differential Transform Method for Numerically

    Office of Scientific and Technical Information (OSTI)

    Evolving Partial Differential Equation Initial-Value Problems (Journal Article) | SciTech Connect Journal Article: An Iterated, Multipoint Differential Transform Method for Numerically Evolving Partial Differential Equation Initial-Value Problems Citation Details In-Document Search Title: An Iterated, Multipoint Differential Transform Method for Numerically Evolving Partial Differential Equation Initial-Value Problems Authors: Finkel, H. J. [1] + Show Author Affiliations (LCF) Publication

  6. Direct Numerical Simulation of Compressible, Turbulent Flow | Argonne

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Leadership Computing Facility Sample slice of the instantaneous density field Sample slice of the instantaneous density field in a Mach 2.3 turbulent boundary layer computed with the HOPS code. The computational mesh for this direct numerical simulation was over 33 billion cells, and was run on up to 102,400 cores under a DoD HPCMP Frontier Project. Nicholas Bisek and Ryan Gosse, Air Force Research Laboratory; Jonathan Poggie, Purdue University Direct Numerical Simulation of Compressible,

  7. Numerical evaluation of effective unsaturated hydraulic properties for

    Office of Scientific and Technical Information (OSTI)

    fractured rocks (Journal Article) | SciTech Connect Journal Article: Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks Citation Details In-Document Search Title: Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service.

  8. Numerical simulation of phase transition problems with explicit interface

    Office of Scientific and Technical Information (OSTI)

    tracking (Journal Article) | SciTech Connect Numerical simulation of phase transition problems with explicit interface tracking Citation Details In-Document Search This content will become publicly available on March 18, 2017 Title: Numerical simulation of phase transition problems with explicit interface tracking Authors: Hu, Yijing ; Shi, Qiangqiang Search SciTech Connect for author "Shi, Qiangqiang" Search SciTech Connect for ORCID "0000000173177251" Search orcid.org

  9. Numerical simulations for low energy nuclear reactions including direct

    Office of Scientific and Technical Information (OSTI)

    channels to validate statistical models (Conference) | SciTech Connect Numerical simulations for low energy nuclear reactions including direct channels to validate statistical models Citation Details In-Document Search Title: Numerical simulations for low energy nuclear reactions including direct channels to validate statistical models Authors: Kawano, Toshihiko [1] + Show Author Affiliations Los Alamos National Laboratory [Los Alamos National Laboratory Publication Date: 2014-01-08 OSTI

  10. A review of recent advances of numerical simulations of microscale fuel processors for hydrogen production

    SciTech Connect (OSTI)

    Holladay, Jamelyn D.; Wang, Yong

    2015-05-01

    Microscale (<5W) reformers for hydrogen production have been investigated for over a decade. These devices are intended to provide hydrogen for small fuel cells. Due to the reformer’s small size, numerical simulations are critical to understand heat and mass transfer phenomena occurring in the systems. This paper reviews the development of the numerical codes and details the reaction equations used. The majority of the devices utilized methanol as the fuel due to methanol’s low reforming temperature and high conversion, although, there are several methane fueled systems. As computational power has decreased in cost and increased in availability, the codes increased in complexity and accuracy. Initial models focused on the reformer, while more recently, the simulations began including other unit operations such as vaporizers, inlet manifolds, and combustors. These codes are critical for developing the next generation systems. The systems reviewed included, plate reactors, microchannel reactors, annulus reactors, wash-coated, packed bed systems.

  11. On the physical and chemical details of alumina atomic layer deposition: A combined experimental and numerical approach

    SciTech Connect (OSTI)

    Pan, Dongqing; Ma, Lulu; Xie, Yuanyuan; Yuan, Chris; Jen, Tien Chien

    2015-03-15

    Alumina thin film is typically studied as a model atomic layer deposition (ALD) process due to its high dielectric constant, high thermal stability, and good adhesion on various wafer surfaces. Despite extensive applications of alumina ALD in microelectronics industries, details on the physical and chemical processes are not yet well understood. ALD experiments are not able to shed adequate light on the detailed information regarding the transient ALD process. Most of current numerical approaches lack detailed surface reaction mechanisms, and their results are not well correlated with experimental observations. In this paper, the authors present a combined experimental and numerical study on the details of flow and surface reactions in alumina ALD using trimethylaluminum and water as precursors. Results obtained from experiments and simulations are compared and correlated. By experiments, growth rate on five samples under different deposition conditions is characterized. The deposition rate from numerical simulation agrees well with the experimental results. Details of precursor distributions in a full cycle of ALD are studied numerically to bridge between experimental observations and simulations. The 3D transient numerical model adopts surface reaction kinetics and mechanisms based on atomic-level studies to investigate the surface deposition process. Surface deposition is shown as a strictly self-limited process in our numerical studies. ALD is a complex strong-coupled fluid, thermal and chemical process, which is not only heavily dependent on the chemical kinetics and surface conditions but also on the flow and material distributions.

  12. Numerical Modeling of Geomechanical Processes Related to CO{sub 2} Injection within Generic Reservoirs

    SciTech Connect (OSTI)

    Eckert, Andreas

    2013-05-31

    In this project generic anticline structures have been used for numerical modeling analyses to study the influence of geometrical parameters, fluid flow boundary conditions, in situ stress regime and inter-bedding friction coefficient on geomechanical risks such as fracture reactivation and fracture generation. The resulting stress states for these structures are also used to determine safe drilling directions and a methodology for wellbore trajection optimization is developed that is applicable for non-Andersonian stress states. The results of the fluid flow simulation show that the type of fluid flow boundary condition is of utmost importance and has significant impact on all injection related parameters. It is recommended that further research is conducted to establish a method to quantify the fluid flow boundary conditions for injection applications. The results of the geomechanical simulation show that in situ stress regime is a crucial, if not the most important, factor determining geomechanical risks. For extension and strike slip stress regimes anticline structures should be favored over horizontally layered basin as they feature higher ΔP{sub c} magnitudes. If sedimentary basins are tectonically relaxed and their state of stress is characterized by the uni-axial strain model the basin is in exact frictional equilibrium and fluids should not be injected. The results also show that low inter bedding friction coefficients effectively decouple layers resulting in lower ΔP{sub c} magnitudes, especially for the compressional stress regime.

  13. Automatic Parallelization of Numerical Python Applications using the Global Arrays Toolkit

    SciTech Connect (OSTI)

    Daily, Jeffrey A.; Lewis, Robert R.

    2011-11-30

    Global Arrays is a software system from Pacific Northwest National Laboratory that enables an efficient, portable, and parallel shared-memory programming interface to manipulate distributed dense arrays. The NumPy module is the de facto standard for numerical calculation in the Python programming language, a language whose use is growing rapidly in the scientific and engineering communities. NumPy provides a powerful N-dimensional array class as well as other scientific computing capabilities. However, like the majority of the core Python modules, NumPy is inherently serial. Using a combination of Global Arrays and NumPy, we have reimplemented NumPy as a distributed drop-in replacement called Global Arrays in NumPy (GAiN). Serial NumPy applications can become parallel, scalable GAiN applications with only minor source code changes. Scalability studies of several different GAiN applications will be presented showing the utility of developing serial NumPy codes which can later run on more capable clusters or supercomputers.

  14. The shallow water equations as a hybrid flow model for the numerical and experimental analysis of hydro power stations

    SciTech Connect (OSTI)

    Ostermann, Lars; Seidel, Christian

    2015-03-10

    The numerical analysis of hydro power stations is an important method of the hydraulic design and is used for the development and optimisation of hydro power stations in addition to the experiments with the physical submodel of a full model in the hydraulic laboratory. For the numerical analysis, 2D and 3D models are appropriate and commonly used.The 2D models refer mainly to the shallow water equations (SWE), since for this flow model a large experience on a wide field of applications for the flow analysis of numerous problems in hydraulic engineering already exists. Often, the flow model is verified by in situ measurements. In order to consider 3D flow phenomena close to singularities like weirs, hydro power stations etc. the development of a hybrid fluid model is advantageous to improve the quality and significance of the global model. Here, an extended hybrid flow model based on the principle of the SWE is presented. The hybrid flow model directly links the numerical model with the experimental data, which may originate from physical full models, physical submodels and in-situ measurements. Hence a wide field of application of the hybrid model emerges including the improvement of numerical models and the strong coupling of numerical and experimental analysis.

  15. Numerical errors in the presence of steep topography: analysis and alternatives

    SciTech Connect (OSTI)

    Lundquist, K A; Chow, F K; Lundquist, J K

    2010-04-15

    It is well known in computational fluid dynamics that grid quality affects the accuracy of numerical solutions. When assessing grid quality, properties such as aspect ratio, orthogonality of coordinate surfaces, and cell volume are considered. Mesoscale atmospheric models generally use terrain-following coordinates with large aspect ratios near the surface. As high resolution numerical simulations are increasingly used to study topographically forced flows, a high degree of non-orthogonality is introduced, especially in the vicinity of steep terrain slopes. Numerical errors associated with the use of terrainfollowing coordinates can adversely effect the accuracy of the solution in steep terrain. Inaccuracies from the coordinate transformation are present in each spatially discretized term of the Navier-Stokes equations, as well as in the conservation equations for scalars. In particular, errors in the computation of horizontal pressure gradients, diffusion, and horizontal advection terms have been noted in the presence of sloping coordinate surfaces and steep topography. In this work we study the effects of these spatial discretization errors on the flow solution for three canonical cases: scalar advection over a mountain, an atmosphere at rest over a hill, and forced advection over a hill. This study is completed using the Weather Research and Forecasting (WRF) model. Simulations with terrain-following coordinates are compared to those using a flat coordinate, where terrain is represented with the immersed boundary method. The immersed boundary method is used as a tool which allows us to eliminate the terrain-following coordinate transformation, and quantify numerical errors through a direct comparison of the two solutions. Additionally, the effects of related issues such as the steepness of terrain slope and grid aspect ratio are studied in an effort to gain an understanding of numerical domains where terrain-following coordinates can successfully be used and those domains where the solution would benefit from the use of the immersed boundary method.

  16. Numerical investigation of spontaneous flame propagation under RCCI conditions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bhagatwala, Ankit V; Sankaran, Ramanan; Kokjohn, Sage; Chen, Jacqueline H

    2015-06-30

    This paper presents results from one and two-dimensional direct numerical simulations under Reactivity Controlled Compression Ignition (RCCI) conditions of a primary reference fuel (PRF) mixture consisting of n-heptane and iso-octane. RCCI uses in-cylinder blending of two fuels with different autoignition characteristics to control combustion phasing and the rate of heat release. These simulations employ an improved model of compression heating through mass source/sink terms developed in a previous work by Bhagatwala et al. (2014), which incorporates feedback from the flow to follow a predetermined experimental pressure trace. Two-dimensional simulations explored parametric variations with respect to temperature stratification, pressure profiles andmore » n-heptane concentration. Furthermore, statistics derived from analysis of diffusion/reaction balances locally normal to the flame surface were used to elucidate combustion characteristics for the different cases. Both deflagration and spontaneous ignition fronts were observed to co-exist, however it was found that higher n-heptane concentration provided a greater degree of flame propagation, whereas lower n-heptane concentration (higher fraction of iso-octane) resulted in more spontaneous ignition fronts. A significant finding was that simulations initialized with a uniform initial temperature and a stratified n-heptane concentration field, resulted in a large fraction of combustion occurring through flame propagation. The proportion of spontaneous ignition fronts increased at higher pressures due to shorter ignition delay when other factors were held constant. For the same pressure and fuel concentration, the contribution of flame propagation to the overall combustion was found to depend on the level of thermal stratification, with higher initial temperature gradients resulting in more deflagration and lower gradients generating more ignition fronts. Statistics of ignition delay are computed to assess the Zel’dovich (1980) theory for the mode of combustion propagation based on ignition delay gradients.« less

  17. Numerical investigation of spontaneous flame propagation under RCCI conditions

    SciTech Connect (OSTI)

    Bhagatwala, Ankit V; Sankaran, Ramanan; Kokjohn, Sage; Chen, Jacqueline H

    2015-06-30

    This paper presents results from one and two-dimensional direct numerical simulations under Reactivity Controlled Compression Ignition (RCCI) conditions of a primary reference fuel (PRF) mixture consisting of n-heptane and iso-octane. RCCI uses in-cylinder blending of two fuels with different autoignition characteristics to control combustion phasing and the rate of heat release. These simulations employ an improved model of compression heating through mass source/sink terms developed in a previous work by Bhagatwala et al. (2014), which incorporates feedback from the flow to follow a predetermined experimental pressure trace. Two-dimensional simulations explored parametric variations with respect to temperature stratification, pressure profiles and n-heptane concentration. Furthermore, statistics derived from analysis of diffusion/reaction balances locally normal to the flame surface were used to elucidate combustion characteristics for the different cases. Both deflagration and spontaneous ignition fronts were observed to co-exist, however it was found that higher n-heptane concentration provided a greater degree of flame propagation, whereas lower n-heptane concentration (higher fraction of iso-octane) resulted in more spontaneous ignition fronts. A significant finding was that simulations initialized with a uniform initial temperature and a stratified n-heptane concentration field, resulted in a large fraction of combustion occurring through flame propagation. The proportion of spontaneous ignition fronts increased at higher pressures due to shorter ignition delay when other factors were held constant. For the same pressure and fuel concentration, the contribution of flame propagation to the overall combustion was found to depend on the level of thermal stratification, with higher initial temperature gradients resulting in more deflagration and lower gradients generating more ignition fronts. Statistics of ignition delay are computed to assess the Zel’dovich (1980) theory for the mode of combustion propagation based on ignition delay gradients.

  18. HIA 2015 DOE Zero Energy Ready Home Case Study: United Way of Long Island Housing Development Corporation, Patchogue, NY

    Energy Savers [EERE]

    Way of Long Island Housing Development Corporation Patchogue, NY DOE ZERO ENERGY READY HOME(tm) The U.S. Department of Energy invites home builders across the country to meet the extraordinary levels of excellence and quality specified in DOE's Zero Energy Ready Home program (formerly known as Challenge Home). Every DOE Zero Energy Ready Home starts with ENERGY STAR Certified Homes Version 3.0 for an energy-efficient home built on a solid foundation of building science research. Advanced

  19. Joint US/Russian study on the development of a decommissioning strategy plan for RBMK-1000 unit No. 1 at the Leningrad Nuclear Power Plant

    SciTech Connect (OSTI)

    1997-12-01

    The objective of this joint U.S./Russian study was to develop a safe, technically feasible, economically acceptable strategy for decommissioning Leningrad Nuclear Power Plant (LNPP) Unit No. 1 as a representative first-generation RBMK-1000 reactor. The ultimate goal in developing the decommissioning strategy was to select the most suitable decommissioning alternative and end state, taking into account the socioeconomic conditions, the regulatory environment, and decommissioning experience in Russia. This study was performed by a group of Russian and American experts led by Kurchatov Institute for the Russian efforts and by the Pacific Northwest National Laboratory for the U.S. efforts and for the overall project.

  20. Experimental Studies for CPF and SCR Model, Control System, and OBD Development for Engines Using Diesel and Biodiesel Fuels

    SciTech Connect (OSTI)

    Johnson, John; Naber, Jeffrey; Parker, Gordon; Yang, Song-Lin; Stevens, Andrews; Pihl, Josh

    2013-04-30

    The research carried out on this project developed experimentally validated Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), and Selective Catalytic Reduction (SCR) high‐fidelity models that served as the basis for the reduced order models used for internal state estimation. The high‐fidelity and reduced order/estimator codes were evaluated by the industrial partners with feedback to MTU that improved the codes. Ammonia, particulate matter (PM) mass retained, PM concentration, and NOX sensors were evaluated and used in conjunction with the estimator codes. The data collected from PM experiments were used to develop the PM kinetics using the high‐fidelity DPF code for both NO2 assisted oxidation and thermal oxidation for Ultra Low Sulfur Fuel (ULSF), and B10 and B20 biodiesel fuels. Nine SAE papers were presented and this technology transfer process should provide the basis for industry to improve the OBD and control of urea injection and fuel injection for active regeneration of the PM in the DPF using the computational techniques developed. This knowledge will provide industry the ability to reduce the emissions and fuel consumption from vehicles in the field. Four MS and three PhD Mechanical Engineering students were supported on this project and their thesis research provided them with expertise in experimental, modeling, and controls in aftertreatment systems.

  1. Development of Alaskan gas hydrate resources. Final report

    SciTech Connect (OSTI)

    Kamath, V.A.; Sharma, G.D.; Patil, S.L.

    1991-06-01

    The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.

  2. Developing grain boundary diagrams as a materials science tool: A case study of nickel-doped molybdenum

    SciTech Connect (OSTI)

    Shi Xiaomeng; Luo Jian

    2011-07-01

    Impurity-based, premelting-like, grain boundary (GB) ''phases'' (complexions) can form in alloys and influence sintering, creep, and microstructural development. Calculation of Phase Diagrams (CalPhaD) methods and Miedema-type statistical interfacial thermodynamic models are combined to forecast the formation and stability of subsolidus quasiliquid GB phases in binary alloys. This work supports a long-range scientific goal of developing ''GB (phase) diagrams'' as a new materials science tool to help controlling the materials fabrication processing and resultant materials properties. Using nickel-doped molybdenum as a model system, a type of GB diagram (called ''{lambda} diagram'') is computed to represent the temperature- and composition-dependent thermodynamic tendency for general GBs to disorder. Subsequently, controlled sintering experiments are conducted to estimate the GB diffusivity as a function of temperature and overall composition, and the experimental results correlate well with the computed GB diagram. Although they are not yet rigorous GB-phase diagrams with well-defined transition lines, the predictability and usefulness of such {lambda} diagrams are demonstrated. Related interfacial thermodynamic models and computational approaches are discussed.

  3. Mild gasification technology development process: Task 3, Bench-scale char upgrading study, February 1988--November 1990

    SciTech Connect (OSTI)

    Carty, R.H.; Onischak, M.; Babu, S.P.; Knight, R.A.; Wootten, J.M.; Duthie, R.G.

    1990-12-01

    The overall objective of this program is to develop mild gasification technology and co-product utilization. The objective of Task 3 was to investigate the necessary steps for upgrading the mild gasification char into potential high-market-value solid products. Recommendations of the Task 1 market survey section formed the basis for selecting three value-added solid products from mild gasification char: form coke, smokeless fuel, and activated adsorbent char. The formation and testing for the form coke co-product involved an evaluation of its briquette strength and reactivity. The measured tensile strength and reactivity of the form coke sample briquettes were in the range of commercial coke, and development tests on a larger scale are recommended. The reaction rate of the form coke carbon with carbon dioxide at 1825{degree}F was measured using a standard procedure. A smokeless fuel briquette with limestone added to control sulfur can be made from mild gasification char in a simple manner. Test results have shown that briquettes with limestone have a heating value comparable to other solid fuels and the limestone can retain up to 88% of the sulfur during combustion in a simple bench-scale combustion test, almost all of it as a stable calcium sulfate. Adsorbent chars were prepared with a standard steam activation procedure and tested for a variety of pertinent property and performance values. Such adsorbents may be better suited for use in some areas, such as the adsorption of low-molecular-weight substances, because of the smaller pore sizes measured in the char. 5 refs., 17 figs., 6 tabs.

  4. DOE Zero Energy Ready Home Case Study: United Way of Long Island Housing Development Corporation, Patchogue, NY

    Broader source: Energy.gov [DOE]

    Case study of a DOE 2015 Housing Innovation Award winning affordable home in the mixed-humid climate that got HERS 40 without PV, -3 with PV, with 2x4 16: on center walls with R-13.5 dense packed cellulose and 1.5” polyiso rigid; basement with 2.5: polyiso on interior; unvented attic with R-48 ocsf under roof deck; ERV tied to wall hung boiler with hydro coil.

  5. A numerical homogenization method for heterogeneous, anisotropic elastic media based on multiscale theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gao, Kai; Chung, Eric T.; Gibson, Richard L.; Fu, Shubin; Efendiev, Yalchin

    2015-06-05

    The development of reliable methods for upscaling fine scale models of elastic media has long been an important topic for rock physics and applied seismology. Several effective medium theories have been developed to provide elastic parameters for materials such as finely layered media or randomly oriented or aligned fractures. In such cases, the analytic solutions for upscaled properties can be used for accurate prediction of wave propagation. However, such theories cannot be applied directly to homogenize elastic media with more complex, arbitrary spatial heterogeneity. We therefore propose a numerical homogenization algorithm based on multiscale finite element methods for simulating elasticmore » wave propagation in heterogeneous, anisotropic elastic media. Specifically, our method used multiscale basis functions obtained from a local linear elasticity problem with appropriately defined boundary conditions. Homogenized, effective medium parameters were then computed using these basis functions, and the approach applied a numerical discretization that is similar to the rotated staggered-grid finite difference scheme. Comparisons of the results from our method and from conventional, analytical approaches for finely layered media showed that the homogenization reliably estimated elastic parameters for this simple geometry. Additional tests examined anisotropic models with arbitrary spatial heterogeneity where the average size of the heterogeneities ranged from several centimeters to several meters, and the ratio between the dominant wavelength and the average size of the arbitrary heterogeneities ranged from 10 to 100. Comparisons to finite-difference simulations proved that the numerical homogenization was equally accurate for these complex cases.« less

  6. A numerical homogenization method for heterogeneous, anisotropic elastic media based on multiscale theory

    SciTech Connect (OSTI)

    Gao, Kai; Chung, Eric T.; Gibson, Richard L.; Fu, Shubin; Efendiev, Yalchin

    2015-06-05

    The development of reliable methods for upscaling fine scale models of elastic media has long been an important topic for rock physics and applied seismology. Several effective medium theories have been developed to provide elastic parameters for materials such as finely layered media or randomly oriented or aligned fractures. In such cases, the analytic solutions for upscaled properties can be used for accurate prediction of wave propagation. However, such theories cannot be applied directly to homogenize elastic media with more complex, arbitrary spatial heterogeneity. We therefore propose a numerical homogenization algorithm based on multiscale finite element methods for simulating elastic wave propagation in heterogeneous, anisotropic elastic media. Specifically, our method used multiscale basis functions obtained from a local linear elasticity problem with appropriately defined boundary conditions. Homogenized, effective medium parameters were then computed using these basis functions, and the approach applied a numerical discretization that is similar to the rotated staggered-grid finite difference scheme. Comparisons of the results from our method and from conventional, analytical approaches for finely layered media showed that the homogenization reliably estimated elastic parameters for this simple geometry. Additional tests examined anisotropic models with arbitrary spatial heterogeneity where the average size of the heterogeneities ranged from several centimeters to several meters, and the ratio between the dominant wavelength and the average size of the arbitrary heterogeneities ranged from 10 to 100. Comparisons to finite-difference simulations proved that the numerical homogenization was equally accurate for these complex cases.

  7. Numerical analysis for high-efficiency GaAs solar cells fabricated on Si substrates

    SciTech Connect (OSTI)

    Yamaguchi, M.; Amano, C.; Itoh, Y.

    1989-07-15

    This paper describes some recent developments in GaAs thin-film solar cells fabricated on Si substrates by metalorganic chemical vapor deposition and numerically analyzes them.GaAs solar cells with efficiency of more than 18% are successfully fabricated on Si substrates by reducing the dislocation density. Photovoltaic properties of GaAs/Si cells are analyzed by considering the effect of nonuniform dislocation distribution on recombination properties of GaAs thin films on Si substrates. Numerical analysis shows that the effect of majority-carrier trapping must be considered. High efficiency GaAs solar cells with total-area efficiency of over 20% on Si substrates can be realized if dislocation density can be reduced to less than 5/times/10/sup 5/ cm/sup /minus/2/.

  8. Engineering development of advanced physical fine coal cleaning for premium fuel applications: Subtask 3.3 - dewatering studies

    SciTech Connect (OSTI)

    Yoon, R. H.; Phillips, D. I.; Sohn, S. M.; Luttrell, G. H.

    1996-10-01

    If successful, the novel Hydrophobic Dewatering (HD) process being developed in this project will be capable of efficiently removing moisture from fine coal without the expense and other related drawbacks associated with mechanical dewatering or thermal drying. In the HD process, a hydrophobic substance is added to a coal-water slurry to displace water from the surface of coal, while the spent hydrophobic substance is recovered for recycling. For this process to have commercialization potential, the amount of butane lost during the process must be small. Earlier testing revealed the ability of the hydrophobic dewatering process to reduce the moisture content of fine coal to a very low amount as well as the determination of potential butane losses by the adsorption of butane onto the coal surface. Work performed in this quarter showed that the state of oxidation affects the amount of butane adsorbed onto the surface of the coal and also affects the final moisture content. the remaining work will involve a preliminary flowsheet of a continuous bench-scale unit and a review of the economics of the system. 1 tab.

  9. An Analysis of Wind Power Development in the Town of Hull, MA, Appendix 2: LaCapra Financial Study

    SciTech Connect (OSTI)

    Adams, Christopher

    2013-06-30

    The financial analysis and summary results presented in this document represent a first cut at an economic assessment of the proposed Hull Offshore Wind Project. Wind turbine price increases have outpaced the materials and labor price pressures faced by nonrenewable power plant developers due to increased demands on a limited pool of turbine manufacturers and offshore installation companies. Moreover, given the size of the proposed offshore facility, it may be difficult to contract with turbine manufacturers and/or foundation companies given the size and scope of competing worldwide demand. The results described in this report assume that such conditions will not significantly impact the prices that will have to be received from the output of the project; rather, the project size may require as a prerequisite that Hull be able to piggyback on other offshore efforts. The financial estimates provided here necessarily feature a range due to uncertainty in a number of project assumptions as well as overall uncertainty in offshore wind costs. Nevertheless, taken together, the analysis provides a ballpark revenue requirement of approximately $157/MWh for the municipal financing option, with higher estimates possible assuming escalation in costs to levels higher than assumed here.

  10. Renewable energy and its potential for carbon emissions reductions in developing countries: Methodology for technology evaluation. Case study application to Mexico

    SciTech Connect (OSTI)

    Corbus, D.; Martinez, M.; Rodriguez, L.; Mark, J.

    1994-08-01

    Many projects have been proposed to promote and demonstrate renewable energy technologies (RETs) in developing countries on the basis of their potential to reduce carbon emissions. However, no uniform methodology has been developed for evaluating RETs in terms of their future carbon emissions reduction potential. This study outlines a methodology for identifying RETs that have the potential for achieving large carbon emissions reductions in the future, while also meeting key criteria for commercialization and acceptability in developing countries. In addition, this study evaluates the connection between technology identification and the selection of projects that are designed to demonstrate technologies with a propensity for carbon emission reductions (e.g., Global Environmental Facility projects). Although this report applies the methodology to Mexico in a case study format, the methodology is broad based and could be applied to any developing country, as well as to other technologies. The methodology used in this report is composed of four steps: technology screening, technology identification, technology deployment scenarios, and estimates of carbon emissions reductions. The four technologies with the highest ranking in the technology identification process for the on-grid category were geothermal, biomass cogeneration, wind, and micro-/mini-hydro. Compressed natural gas (CNG) was the alternative that received the highest ranking for the transportation category.

  11. Research and development of Proton-Exchange-Membrane (PEM) fuel cell system for transportation applications. Fuel cell infrastructure and commercialization study

    SciTech Connect (OSTI)

    1996-11-01

    This paper has been prepared in partial fulfillment of a subcontract from the Allison Division of General Motors under the terms of Allison`s contract with the U.S. Department of Energy (DE-AC02-90CH10435). The objective of this task (The Fuel Cell Infrastructure and Commercialization Study) is to describe and prepare preliminary evaluations of the processes which will be required to develop fuel cell engines for commercial and private vehicles. This report summarizes the work undertaken on this study. It addresses the availability of the infrastructure (services, energy supplies) and the benefits of creating public/private alliances to accelerate their commercialization. The Allison prime contract includes other tasks related to the research and development of advanced solid polymer fuel cell engines and preparation of a demonstration automotive vehicle. The commercialization process starts when there is sufficient understanding of a fuel cell engine`s technology and markets to initiate preparation of a business plan. The business plan will identify each major step in the design of fuel cell (or electrochemical) engines, evaluation of the markets, acquisition of manufacturing facilities, and the technical and financial resources which will be required. The process will end when one or more companies have successfully developed and produced fuel cell engines at a profit. This study addressed the status of the information which will be required to prepare business plans, develop the economic and market acceptance data, and to identify the mobility, energy and environment benefits of electrochemical or fuel cell engines. It provides the reader with information on the status of fuel cell or electrochemical engine development and their relative advantages over competitive propulsion systems. Recommendations and descriptions of additional technical and business evaluations that are to be developed in more detail in Phase II, are included.

  12. Picosecond dynamics of reactions in the liquid phase: studies of iodine photodissociation and development of new laser techniques

    SciTech Connect (OSTI)

    Berg, M.A.

    1985-09-01

    Iodine photodissociation and recombination was studied as a model for processes common to chemical reaction in the liquid phase. Picosecond transient absorption measurements from 1000 to 295 nm were used to monitor the dynamics in a variety of solvents. Most of the atoms which undergo geminate recombination were found to do so in less than or equal to 15 ps, in agreement with the results of existing molecular dynamics simulations. Vibrational relaxation times vary from approx.15 ps near the middle of the ground state well to approx.150 ps for complete relaxation to v = 0. The prediction of strong resonant vibrational energy transfer to chlorinated methane solvents was not supported, but some evidence for this mechanism was found for alkane solvents. Current theory is unable to explain the large variation (65 to 2700 ps) of the excited A'-state lifetime in various solvents. The 10-Hz amplified, synchronously-pumped dye laser which was used in these studies is described and characterized. SERS (Stimulated Electronic Raman Scattering) and difference frequency mixing were used in the generation of the infrared and far-infrared, respectively. 54 refs., 38 figs., 3 tabs. (WRF)

  13. Large Eddy Simulation of Wind Turbine Wakes. Detailed Comparisons of Two Codes Focusing on Effects of Numerics and Subgrid Modeling

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Martinez-Tossas, Luis A.; Churchfield, Matthew J.; Meneveau, Charles

    2015-06-18

    In this work we report on results from a detailed comparative numerical study from two Large Eddy Simulation (LES) codes using the Actuator Line Model (ALM). The study focuses on prediction of wind turbine wakes and their breakdown when subject to uniform inflow. Previous studies have shown relative insensitivity to subgrid modeling in the context of a finite-volume code. The present study uses the low dissipation pseudo-spectral LES code from Johns Hopkins University (LESGO) and the second-order, finite-volume OpenFOAMcode (SOWFA) from the National Renewable Energy Laboratory. When subject to uniform inflow, the loads on the blades are found to bemore » unaffected by subgrid models or numerics, as expected. The turbulence in the wake and the location of transition to a turbulent state are affected by the subgrid-scale model and the numerics.« less

  14. Development, analysis, and evaluation of a commercial software framework for the study of Extremely Low Probability of Rupture (xLPR) events at nuclear power plants.

    SciTech Connect (OSTI)

    Kalinich, Donald A.; Helton, Jon Craig; Sallaberry, Cedric M.; Mattie, Patrick D.

    2010-12-01

    Sandia National Laboratories (SNL) participated in a Pilot Study to examine the process and requirements to create a software system to assess the extremely low probability of pipe rupture (xLPR) in nuclear power plants. This project was tasked to develop a prototype xLPR model leveraging existing fracture mechanics models and codes coupled with a commercial software framework to determine the framework, model, and architecture requirements appropriate for building a modular-based code. The xLPR pilot study was conducted to demonstrate the feasibility of the proposed developmental process and framework for a probabilistic code to address degradation mechanisms in piping system safety assessments. The pilot study includes a demonstration problem to assess the probability of rupture of DM pressurizer surge nozzle welds degraded by primary water stress-corrosion cracking (PWSCC). The pilot study was designed to define and develop the framework and model; then construct a prototype software system based on the proposed model. The second phase of the project will be a longer term program and code development effort focusing on the generic, primary piping integrity issues (xLPR code). The results and recommendations presented in this report will be used to help the U.S. Nuclear Regulatory Commission (NRC) define the requirements for the longer term program.

  15. Translation and integration of numerical atomic orbitals in linear molecules

    SciTech Connect (OSTI)

    Heinsmki, Sami

    2014-02-14

    We present algorithms for translation and integration of atomic orbitals for LCAO calculations in linear molecules. The method applies to arbitrary radial functions given on a numerical mesh. The algorithms are based on pseudospectral differentiation matrices in two dimensions and the corresponding two-dimensional Gaussian quadratures. As a result, multicenter overlap and Coulomb integrals can be evaluated effectively.

  16. Simple intrinsic defects in InAs : numerical predictions.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2013-03-01

    This Report presents numerical tables summarizing properties of intrinsic defects in indium arsenide, InAs, as computed by density functional theory using semi-local density functionals, intended for use as reference tables for a defect physics package in device models.

  17. A three-dimensional numerical model of predevelopment conditions in the Death Valley regional ground-water flow system, Nevada and California

    SciTech Connect (OSTI)

    D'Agnese, F.A.; O'Brien, G.M.; Faunt, C.C.; Belcher, W.R.; San Juan, Carma

    2002-11-22

    In the early 1990's, two numerical models of the Death Valley regional ground-water flow system were developed by the U.S. Department of Energy. In general, the two models were based on the same basic hydrogeologic data set. In 1998, the U.S. Department of Energy requested that the U.S. Geological Survey develop and maintain a ground-water flow model of the Death Valley region in support of U.S. Department of Energy programs at the Nevada Test Site. The purpose of developing this ''second-generation'' regional model was to enhance the knowledge and understanding of the ground-water flow system as new information and tools are developed. The U.S. Geological Survey also was encouraged by the U.S. Department of Energy to cooperate to the fullest extent with other Federal, State, and local entities in the region to take advantage of the benefits of their knowledge and expertise. The short-term objective of the Death Valley regional ground-water flow system project was to develop a steady-stat e representation of the predevelopment conditions of the ground-water flow system utilizing the two geologic interpretations used to develop the previous numerical models. The long-term objective of this project was to construct and calibrate a transient model that simulates the ground-water conditions of the study area over the historical record that utilizes a newly interpreted hydrogeologic conceptual model. This report describes the result of the predevelopment steady-state model construction and calibration.

  18. A SCOPING STUDY: Development of Probabilistic Risk Assessment Models for Reactivity Insertion Accidents During Shutdown In U.S. Commercial Light Water Reactors

    SciTech Connect (OSTI)

    S. Khericha

    2011-06-01

    This report documents the scoping study of developing generic simplified fuel damage risk models for quantitative analysis from inadvertent reactivity insertion events during shutdown (SD) in light water pressurized and boiling water reactors. In the past, nuclear fuel reactivity accidents have been analyzed both mainly deterministically and probabilistically for at-power and SD operations of nuclear power plants (NPPs). Since then, many NPPs had power up-rates and longer refueling intervals, which resulted in fuel configurations that may potentially respond differently (in an undesirable way) to reactivity accidents. Also, as shown in a recent event, several inadvertent operator actions caused potential nuclear fuel reactivity insertion accident during SD operations. The set inadvertent operator actions are likely to be plant- and operation-state specific and could lead to accident sequences. This study is an outcome of the concern which arose after the inadvertent withdrawal of control rods at Dresden Unit 3 in 2008 due to operator actions in the plant inadvertently three control rods were withdrawn from the reactor without knowledge of the main control room operator. The purpose of this Standardized Plant Analysis Risk (SPAR) Model development project is to develop simplified SPAR Models that can be used by staff analysts to perform risk analyses of operating events and/or conditions occurring during SD operation. These types of accident scenarios are dominated by the operator actions, (e.g., misalignment of valves, failure to follow procedures and errors of commissions). Human error probabilities specific to this model were assessed using the methodology developed for SPAR model human error evaluations. The event trees, fault trees, basic event data and data sources for the model are provided in the report. The end state is defined as the reactor becomes critical. The scoping study includes a brief literature search/review of historical events, developments of a small set of comprehensive event trees and fault trees and recommendation for future work.

  19. Numerical solution of the time dependent Ginzburg-Landau equations for mixed (d + s)-wave superconductors

    SciTech Connect (OSTI)

    Gonalves, W. C.; Sardella, E.; UNESP-Universidade Estadual Paulista, IPMet-Instituto de Pesquisas Meteorolgicas, CEP 17048-699 Bauru, SP ; Becerra, V. F.; Miloevi?, M. V.; Peeters, F. M.; Departamento de Fsica, Universidade Federal do Cear, 60455-900 Fortaleza, Cear

    2014-04-15

    The time-dependent Ginzburg-Landau formalism for (d + s)-wave superconductors and their representation using auxiliary fields is investigated. By using the link variable method, we then develop suitable discretization of these equations. Numerical simulations are carried out for a mesoscopic superconductor in a homogeneous perpendicular magnetic field which revealed peculiar vortex states.

  20. Development of a high-density gas-jet target for nuclear astrophysics and reaction studies with rare isotope beams. Final Report

    SciTech Connect (OSTI)

    Uwe, Greife

    2014-08-12

    The purpose of this project was to develop a high-density gas jet target that will enable a new program of transfer reaction studies with rare isotope beams and targets of hydrogen and helium that is not currently possible and will have an important impact on our understanding of stellar explosions and of the evolution of nuclear shell structure away from stability. This is the final closeout report for the project.

  1. he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study

    SciTech Connect (OSTI)

    Keene, William C.; Long, Michael S.

    2013-05-20

    This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistry??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earth??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

  2. Numerical Modeling At Neal Hot Springs Geothermal Area (U.S....

    Open Energy Info (EERE)

    Area Exploration Technique Numerical Modeling Activity Date 2011 - 2011 Usefulness useful DOE-funding Unknown Exploration Basis A numerical reservoir model was created to...

  3. Studies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Studies of the Cosmic Ray Flux in MicroBooNE Katherine Woodruff with Vassili Papavassiliou (Prof.) Stephen Pate (Prof.) Tia Miceli (Postdoc) Alistair McLean (Undergraduate) for the MicroBooNE Collaboration APS April Meeting April 7, 2014 Katherine Woodruff, et al. New Mexico State University 1/14 MicroBooNE MicroBooNE is a liquid Argon time projection chamber (LArTPC) designed to detect neutrino interactions The liquid argon serves as a target for a neutrino beam 87 ton active volume (170 ton

  4. A 2-Stage Genome-Wide Association Study to Identify Single Nucleotide Polymorphisms Associated With Development of Erectile Dysfunction Following Radiation Therapy for Prostate Cancer

    SciTech Connect (OSTI)

    Kerns, Sarah L.; Departments of Pathology and Genetics, Albert Einstein College of Medicine, Bronx, New York ; Stock, Richard; Stone, Nelson; Department of Urology, Mount Sinai School of Medicine, New York, New York ; Buckstein, Michael; Shao, Yongzhao; Campbell, Christopher; Rath, Lynda; De Ruysscher, Dirk; Lammering, Guido; Hixson, Rosetta; Cesaretti, Jamie; Terk, Mitchell; Ostrer, Harry; Rosenstein, Barry S.

    2013-01-01

    Purpose: To identify single nucleotide polymorphisms (SNPs) associated with development of erectile dysfunction (ED) among prostate cancer patients treated with radiation therapy. Methods and Materials: A 2-stage genome-wide association study was performed. Patients were split randomly into a stage I discovery cohort (132 cases, 103 controls) and a stage II replication cohort (128 cases, 102 controls). The discovery cohort was genotyped using Affymetrix 6.0 genome-wide arrays. The 940 top ranking SNPs selected from the discovery cohort were genotyped in the replication cohort using Illumina iSelect custom SNP arrays. Results: Twelve SNPs identified in the discovery cohort and validated in the replication cohort were associated with development of ED following radiation therapy (Fisher combined P values 2.1 Multiplication-Sign 10{sup -5} to 6.2 Multiplication-Sign 10{sup -4}). Notably, these 12 SNPs lie in or near genes involved in erectile function or other normal cellular functions (adhesion and signaling) rather than DNA damage repair. In a multivariable model including nongenetic risk factors, the odds ratios for these SNPs ranged from 1.6 to 5.6 in the pooled cohort. There was a striking relationship between the cumulative number of SNP risk alleles an individual possessed and ED status (Sommers' D P value = 1.7 Multiplication-Sign 10{sup -29}). A 1-allele increase in cumulative SNP score increased the odds for developing ED by a factor of 2.2 (P value = 2.1 Multiplication-Sign 10{sup -19}). The cumulative SNP score model had a sensitivity of 84% and specificity of 75% for prediction of developing ED at the radiation therapy planning stage. Conclusions: This genome-wide association study identified a set of SNPs that are associated with development of ED following radiation therapy. These candidate genetic predictors warrant more definitive validation in an independent cohort.

  5. Experimental and numerical analysis of metal leaching from fly ash-amended highway bases

    SciTech Connect (OSTI)

    Cetin, Bora; Aydilek, Ahmet H.; Li, Lin

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer This study is the evaluation of leaching potential of fly ash-lime mixed soils. Black-Right-Pointing-Pointer This objective is met with experimental and numerical analysis. Black-Right-Pointing-Pointer Zn leaching decreases with increase in fly ash content while Ba, B, Cu increases. Black-Right-Pointing-Pointer Decrease in lime content promoted leaching of Ba, B and Cu while Zn increases. Black-Right-Pointing-Pointer Numerical analysis predicted lower field metal concentrations. - Abstract: A study was conducted to evaluate the leaching potential of unpaved road materials (URM) mixed with lime activated high carbon fly ashes and to evaluate groundwater impacts of barium, boron, copper, and zinc leaching. This objective was met by a combination of batch water leach tests, column leach tests, and computer modeling. The laboratory tests were conducted on soil alone, fly ash alone, and URM-fly ash-lime kiln dust mixtures. The results indicated that an increase in fly ash and lime content has significant effects on leaching behavior of heavy metals from URM-fly ash mixture. An increase in fly ash content and a decrease in lime content promoted leaching of Ba, B and Cu whereas Zn leaching was primarily affected by the fly ash content. Numerically predicted field metal concentrations were significantly lower than the peak metal concentrations obtained in laboratory column leach tests, and field concentrations decreased with time and distance due to dispersion in soil vadose zone.

  6. Recent numerical and algorithmic advances within the volume tracking framework for modeling interfacial flows

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    François, Marianne M.

    2015-05-28

    A review of recent advances made in numerical methods and algorithms within the volume tracking framework is presented. The volume tracking method, also known as the volume-of-fluid method has become an established numerical approach to model and simulate interfacial flows. Its advantage is its strict mass conservation. However, because the interface is not explicitly tracked but captured via the material volume fraction on a fixed mesh, accurate estimation of the interface position, its geometric properties and modeling of interfacial physics in the volume tracking framework remain difficult. Several improvements have been made over the last decade to address these challenges.more » In this study, the multimaterial interface reconstruction method via power diagram, curvature estimation via heights and mean values and the balanced-force algorithm for surface tension are highlighted.« less

  7. Numerical method for shear bands in ductile metal with inclusions

    SciTech Connect (OSTI)

    Plohr, Jee Yeon N [Los Alamos National Laboratory; Plohr, Bradley J [Los Alamos National Laboratory

    2010-01-01

    A numerical method for mesoscale simulation of high strain-rate loading of ductile metal containing inclusions is described. Because of small-scale inhomogeneities, such a composite material is prone to localized shear deformation (adiabatic shear bands). The modeling framework is the Generalized Method of Cells of Paley and Aboudi [Mech. Materials, vol. 14, pp. /27-139, 1992], which ensures that the micromechanical response of the material is reflected in the behavior of the composite at the mesoscale. To calculate the effective plastic strain rate when shear bands are present, the analytic and numerical analysis of shear bands by Glimm, Plohr, and Sharp [Mech. Materials, vol. 24, pp. 31-41, 1996] is adapted and extended.

  8. Tropical anvil cirrus evolution from observations and numerical simulations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tropical anvil cirrus evolution from observations and numerical simulations Deng, Min University of Utah Mace, Gerald University of Utah Category: Modeling The tropical anvil cirrus formation and maintenance mechanism evolves during the life cycle of the mesoscale complexes. The large heating-rate gradients within the cloud may induce dynamical responses which would tend to lift and spread the anvils (Ackerman, 1988). The radiation heating can act as sources of turbulence and affect the anvil

  9. Direct Numerical Simulations and Robust Predictions of Cloud Cavitation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Collapse | Argonne Leadership Computing Facility Initiation of cloud cavitation collapse for 50,000 bubbles Initiation of cloud cavitation collapse for 50,000 bubbles. Jonas Sukys, ETH Zurich Direct Numerical Simulations and Robust Predictions of Cloud Cavitation Collapse PI Name: Petros Koumoutsakos PI Email: petros@ethz.ch Institution: ETH Zurich Allocation Program: INCITE Allocation Hours at ALCF: 72 Million Year: 2016 Research Domain: Engineering Cloud cavitation collapse-the evolution

  10. Numerical Simulation of Ni Grain Growth in a Thermal Gradient

    Office of Scientific and Technical Information (OSTI)

    665C Numerical Simulation of Ni Grain Growth in a Thermal Gradient Sandia National Laboratories John A. Mitchell and Veena Tikare Sandia National Laboratories, Albuquerque New Mexico 87185 Towards Grain Size Predictions for Heat Treatment^ Processes Strength, toughness & crack growth resistance in nickel alloys is enhanced by control over microstructure through multiple stages of wrought processing Heat treatments stimulate grain growth and evolution In this work, a Potts model is used to

  11. COLLOQUIUM: History, Applications, Numerical Values and Problems with the

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Calculation of EROI - Energy Return on (Energy) Investment | Princeton Plasma Physics Lab March 2, 2016, 4:15pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: History, Applications, Numerical Values and Problems with the Calculation of EROI - Energy Return on (Energy) Investment Professor Charles Hall State University of NY College of Environmental Science and Forestry Plants and animals are subjected to fierce selective pressure to do the "right thing" energetically, that is to

  12. Numerical simulations of the decay of primordial magnetic turbulence

    SciTech Connect (OSTI)

    Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON P3E 2C (Canada); Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Brandenburg, Axel [Nordita, AlbaNova University Center, Roslagstullsbacken 23, 10691 Stockholm (Sweden); Department of Astronomy, Stockholm University, SE 10691 Stockholm (Sweden); Tevzadze, Alexander G. [Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Faculty of Exact and Natural Sciences, Tbilisi State University, 1 Chavchavadze Avenue Tbilisi, GE-0128 (Georgia); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)

    2010-06-15

    We perform direct numerical simulations of forced and freely decaying 3D magnetohydrodynamic turbulence in order to model magnetic field evolution during cosmological phase transitions in the early Universe. Our approach assumes the existence of a magnetic field generated either by a process during inflation or shortly thereafter, or by bubble collisions during a phase transition. We show that the final configuration of the magnetic field depends on the initial conditions, while the velocity field is nearly independent of initial conditions.

  13. Los Alamos National Laboratory communicators capture numerous awards from

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Society for Technical Communication Society for Technical Communication Awards Los Alamos National Laboratory communicators capture numerous awards from Society for Technical Communication Three Los Alamos entries garnered Distinguished Technical Communication awards, the competition's highest award category. April 15, 2010 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering

  14. Direct numerical simulations of fluid flow, heat transfer and phase changes

    SciTech Connect (OSTI)

    Juric, D.; Tryggvason, G.; Han, J.

    1997-04-01

    Direct numerical simulations of fluid flow, heat transfer, and phase changes are presented. The simulations are made possible by a recently developed finite difference/front tracking method based on the one-field formulation of the governing equations where a single set of conservation equations is written for all the phases involved. The conservation equations are solved on a fixed rectangular grid, but the phase boundaries are kept sharp by tracking them explicitly by a moving grid of lower dimension. The method is discussed and applications to boiling heat transfer and the solidification of drops colliding with a wall are shown.

  15. Numerical solutions of magnetohydrodynamic stability of axisymmetric toroidal plasmas using cubic B-spline finite element method

    SciTech Connect (OSTI)

    Cheng, C.Z.

    1988-12-01

    A nonvariational ideal MHD stability code (NOVA) has been developed. In a general flux coordinate (/psi/, theta, /zeta/) system with an arbitrary Jacobian, the NOVA code employs Fourier expansions in the generalized poloidal angle theta and generalized toroidal angle /zeta/ directions, and cubic-B spline finite elements in the radial /psi/ direction. Extensive comparisons with these variational ideal MHD codes show that the NOVA code converges faster and gives more accurate results. An extended version of NOVA is developed to integrate non-Hermitian eigenmode equations due to energetic particles. The set of non-Hermitian integro-differential eigenmode equations is numerically solved by the NOVA-K code. We have studied the problems of the stabilization of ideal MHD internal kink modes by hot particle pressure and the excitation of ''fishbone'' internal kink modes by resonating with the energetic particle magnetic drift frequency. Comparisons with analytical solutions show that the values of the critical ..beta../sub h/ from the analytical theory can be an order of magnitude different from those computed by the NOVA-K code. 24 refs., 11 figs., 1 tab.

  16. Transient productivity index for numerical well test simulations

    SciTech Connect (OSTI)

    Blanc, G.; Ding, D.Y.; Ene, A.

    1997-08-01

    The most difficult aspect of numerical simulation of well tests is the treatment of the Bottom Hole Flowing (BHF) Pressure. In full field simulations, this pressure is derived from the Well-block Pressure (WBP) using a numerical productivity index which accounts for the grid size and permeability, and for the well completion. This productivity index is calculated assuming a pseudo-steady state flow regime in the vicinity of the well and is therefore constant during the well production period. Such a pseudo-steady state assumption is no longer valid for the early time of a well test simulation as long as the pressure perturbation has not reached several grid-blocks around the well. This paper offers two different solutions to this problem: (1) The first one is based on the derivation of a Numerical Transient Productivity Index (NTPI) to be applied to Cartesian grids; (2) The second one is based on the use of a Corrected Transmissibility and Accumulation Term (CTAT) in the flow equation. The representation of the pressure behavior given by both solutions is far more accurate than the conventional one as shown by several validation examples which are presented in the following pages.

  17. A Numerical Model Without Truncation Error for a Steady-State Analysis of a Once-Through Steam Generator

    SciTech Connect (OSTI)

    Sim, Yoon Sub; Kim, Eui Kwang; Eoh, Jae Hyuk [Korea Atomic Energy Research Institute (Korea, Republic of)

    2005-06-15

    To overcome the drawbacks of conventional schemes for a numerical analysis of a steam generator (SG), an efficient numerical model has been developed to analyze the steady state of a once-through-type SG where the feedwater is heated to superheated steam. In the developed model, the temperature and enthalpy are defined at the boundary of a calculation cell, and the exact solutions for the temperature distribution in a calculation cell are utilized. This feature of the developed model frees calculation from the undesirable effects of numerical diffusion, and only a small number of nodes are required. Also, the developed model removes the ambiguity from the parameter values at the inlet and exit of a calculation.The BoSupSG-SS computer code was developed by using the analysis model, and it performed well with only three calculation nodes to analyze a superheated SG. The developed model can be effectively used for the cases where a fast one-dimensional calculation is required such as an SG or system design analysis.

  18. Dynamic density functional theory with hydrodynamic interactions: Theoretical development and application in the study of phase separation in gas-liquid systems

    SciTech Connect (OSTI)

    Kikkinides, E. S.; Monson, P. A.

    2015-03-07

    Building on recent developments in dynamic density functional theory, we have developed a version of the theory that includes hydrodynamic interactions. This is achieved by combining the continuity and momentum equations eliminating velocity fields, so the resulting model equation contains only terms related to the fluid density and its time and spatial derivatives. The new model satisfies simultaneously continuity and momentum equations under the assumptions of constant dynamic or kinematic viscosity and small velocities and/or density gradients. We present applications of the theory to spinodal decomposition of subcritical temperatures for one-dimensional and three-dimensional density perturbations for both a van der Waals fluid and for a lattice gas model in mean field theory. In the latter case, the theory provides a hydrodynamic extension to the recently studied dynamic mean field theory. We find that the theory correctly describes the transition from diffusive phase separation at short times to hydrodynamic behaviour at long times.

  19. Correction of steel casing effect for density log using numerical and experimental methods in the slim borehole

    SciTech Connect (OSTI)

    Hwang, Seho; Shin, Jehyun; Kim, Jongman; Won, Byeongho

    2015-03-10

    Density log is widely applied for a variety of fields such as the petroleum exploration, mineral exploration, and geotechnical survey. The logging condition of density log is normally open holes but there are frequently cased boreholes. The primary calibration curve by slim hole logging manufacturer is normally the calibration curves for the variation of borehole diameter. In this study, we have performed the correction of steel casing effects using numerical and experimental methods. We have performed numerical modeling using the Monte Carlo N-Particle (MCNP) code based on Monte Carlo method, and field experimental method from open and cased hole log. In this study, we used the FDGS (Formation Density Gamma Sonde) for slim borehole with a 100 mCi 137Cs source, three inch borehole and steel casing. The casing effect between numerical and experimental method is well matched.

  20. Environmental and economic development consequences of forest and agricultural sector policies in Latin America (a synthesis of case studies of Costa Rica, Ecuador, and Bolivia)

    SciTech Connect (OSTI)

    Stewart, R.; Gibson, D.

    1994-04-15

    This paper draws heavily on the results of case studies in Bolivia, Costa Rica, and Ecuador to explain how sectoral policies have tilted land use decisions against forestry and in favor of agriculture, and to present estimates of the economic development effects of those decisions. The paper summarizes information on forests and forest industries of the three countries, and it describes the framework within which policies are designed. It presents the effects of sectoral policies on land use and forest management, and then quantifies and discusses economic costs of relevant sectoral policies. Conclusions and recommendations for policy reform are offered.

  1. Experimental and Numerical Examination of the Thermal Transmittance of High Performance Window Frames

    SciTech Connect (OSTI)

    Gustavsen Ph.D., Arild; Goudey, Howdy; Kohler, Christian; Arasteh P.E., Dariush; Uvslokk, Sivert; Talev, Goce; Petter Jelle Ph.D., Bjorn

    2010-06-17

    While window frames typically represent 20-30percent of the overall window area, their impact on the total window heat transfer rates may be much larger. This effect is even greater in low-conductance (highly insulating) windows which incorporate very low conductance glazings. Developing low-conductance window frames requires accurate simulation tools for product research and development. The Passivhaus Institute in Germany states that windows (glazing and frames, combined) should have U-values not exceeding 0.80 W/(m??K). This has created a niche market for highly insulating frames, with frame U-values typically around 0.7-1.0 W/(m2 cdot K). The U-values reported are often based on numerical simulations according to international simulation standards. It is prudent to check the accuracy of these calculation standards, especially for high performance products before more manufacturers begin to use them to improve other product offerings. In this paper the thermal transmittance of five highly insulating window frames (three wooden frames, one aluminum frame and one PVC frame), found from numerical simulations and experiments, are compared. Hot box calorimeter results are compared with numerical simulations according to ISO 10077-2 and ISO 15099. In addition CFD simulations have been carried out, in order to use the most accurate tool available to investigate the convection and radiation effects inside the frame cavities. Our results show that available tools commonly used to evaluate window performance, based on ISO standards, give good overall agreement, but specific areas need improvement.

  2. Numerical simulations of impulsively generated Alfvn waves in solar magnetic arcades

    SciTech Connect (OSTI)

    Chmielewski, P.; Murawski, K.; Musielak, Z. E.; Srivastava, A. K.

    2014-09-20

    We perform numerical simulations of impulsively generated Alfvn waves in an isolated solar arcade, which is gravitationally stratified and magnetically confined. We study numerically the propagation of Alfvn waves along the magnetic structure that extends from the lower chromosphere, where the waves are generated, to the solar corona, and analyze the influence of the arcade size and the width of the initial pulses on the wave propagation and reflection. Our model of the solar atmosphere is constructed by adopting the temperature distribution based on the semi-empirical VAL-C model and specifying the curved magnetic field lines that constitute the asymmetric magnetic arcade. The propagation and reflection of Alfvn waves in this arcade is described by 2.5-dimensional magnetohydrodynamic equations that are numerically solved by the FLASH code. Our numerical simulations reveal that the Alfvn wave amplitude decreases as a result of a partial reflection of Alfvn waves in the solar transition region, and that the waves that are not reflected leak through the transition region and reach the solar corona. We also find the decrement of the attenuation time of Alfvn waves for wider initial pulses. Moreover, our results show that the propagation of Alfvn waves in the arcade is affected by the spatial dependence of the Alfvn speed, which leads to phase mixing that is stronger for more curved and larger magnetic arcades. We discuss the processes that affect the Alfvn wave propagation in an asymmetric solar arcade and conclude that besides phase mixing in the magnetic field configuration, the plasma properties of the arcade, the size of the initial pulse, and the structure of the solar transition region all play a vital role in the Alfvn wave propagation.

  3. Improving the quality of numerical software through user-centered design

    SciTech Connect (OSTI)

    Pancake, C. M., Oregon State University

    1998-06-01

    The software interface - whether graphical, command-oriented, menu-driven, or in the form of subroutine calls - shapes the user`s perception of what software can do. It also establishes upper bounds on software usability. Numerical software interfaces typically are based on the designer`s understanding of how the software should be used. That is a poor foundation for usability, since the features that are ``instinctively right`` from the developer`s perspective are often the very ones that technical programmers find most objectionable or most difficult to learn. This paper discusses how numerical software interfaces can be improved by involving users more actively in design, a process known as user-centered design (UCD). While UCD requires extra organization and effort, it results in much higher levels of usability and can actually reduce software costs. This is true not just for graphical user interfaces, but for all software interfaces. Examples show how UCD improved the usability of a subroutine library, a command language, and an invocation interface.

  4. Case studies of the legal and institutional obstacles and incentives to the development of small-scale hydroelectric power: South Columbia Basin Irrigation District, Pasco, Washington

    SciTech Connect (OSTI)

    Schwartz, L.

    1980-05-01

    The case study concerns two modern human uses of the Columbia River - irrigation aimed at agricultural land reclamation and hydroelectric power. The Grand Coulee Dam has become synonomous with large-scale generation of hydroelectric power providing the Pacific Northwest with some of the least-expensive electricity in the United States. The Columbia Basin Project has created a half-million acres of farmland in Washington out of a spectacular and vast desert. The South Columbia River Basin Irrigation District is seeking to harness the energy present in the water which already runs through its canals, drains, and wasteways. The South District's development strategy is aimed toward reducing the costs its farmers pay for irrigation and raising the capital required to serve the remaining 550,000 acres originally planned as part of the Columbia Basin Project. The economic, institutional, and regulatory problems of harnessing the energy at site PEC 22.7, one of six sites proposed for development, are examined in this case study.

  5. Studies of adsorption characteristics of activated carbons down to 4.5 K for the development of cryosorption pumps for fusion systems

    SciTech Connect (OSTI)

    Kasthurirengan, S.; Behera, U.; Vivek, G. A.; Krishnamoorthy, V.; Gangradey, R.; Udgata, S. S.; Tripati, V. S.

    2014-01-29

    Cryosorption pump is the only possible device to pump helium, hydrogen and its isotopes in fusion environment, such as high magnetic field and high plasma temperatures. Activated carbons are known to be the most suitable adsorbent in the development of cryosorption pumps. For this purpose, the data of adsorption characteristics of activated carbons in the temperature range 4.5 K to 77 K are needed, but are not available in the literature. For obtaining the above data, a commercial micro pore analyzer operating at 77 K has been integrated with a two stage GM cryocooler, which enables the cooling of the sample temperature down to 4.5 K. A heat switch mounted between the second stage cold head and the sample chamber helps to raise the sample chamber temperature to 77 K without affecting the performance of the cryocooler. The detailed description of this system is presented elsewhere. This paper presents the results of experimental studies of adsorption isotherms measured on different types of activated carbons in the form of granules, globules, flake knitted and non-woven types in the temperature range 4.5 K to 10 K using Helium gas as the adsorbate. The above results are analyzed to obtain the pore size distributions and surface areas of the activated carbons. The effect of adhesive used for bonding the activated carbons to the panels is also studied. These results will be useful to arrive at the right choice of activated carbon to be used for the development of cryosorption pumps.

  6. Numerical simulation of carbon arc discharge for nanoparticle synthesis

    SciTech Connect (OSTI)

    Kundrapu, M.; Keidar, M.

    2012-07-15

    Arc discharge with catalyst-filled carbon anode in helium background was used for the synthesis of carbon nanoparticles. In this paper, we present the results of numerical simulation of carbon arc discharges with arc current varying from 10 A to 100 A in a background gas pressure of 68 kPa. Anode sublimation rate and current voltage characteristics are compared with experiments. Distribution of temperature and species density, which is important for the estimation of the growth of nanoparticles, is obtained. The probable location of nanoparticle growth region is identified based on the temperature range for the formation of catalyst clusters.

  7. High numerical aperture projection system for extreme ultraviolet projection lithography

    DOE Patents [OSTI]

    Hudyma, Russell M. (San Ramon, CA)

    2000-01-01

    An optical system is described that is compatible with extreme ultraviolet radiation and comprises five reflective elements for projecting a mask image onto a substrate. The five optical elements are characterized in order from object to image as concave, convex, concave, convex, and concave mirrors. The optical system is particularly suited for ring field, step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width which effectively minimizes dynamic distortion. The present invention allows for higher device density because the optical system has improved resolution that results from the high numerical aperture, which is at least 0.14.

  8. Numerical Modeling of WECS at Ecole Centrale de Nantes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    LHEEA CNRS UMR 6598 Laboratoire de recherche en Hydrodynamique Énergétique et Environnement Atmosphérique Numerical modelling of Wave Energy Converters at LHEEA Lab Ecole Centrale de Nantes (France) Alain H. CLEMENT Senior researcher Ocean Energy and Ocean Waves Group NREL MHK Workshop - Broomfield (CO) - 9-10 July 2012 LHEEA CNRS UMR 6598 Laboratoire de recherche en Hydrodynamique Énergétique et Environnement Atmosphérique NREL MHK Workshop - Broomfield (CO) - 9-10 July 2012 The Ocean

  9. Numerical calculation of the ion polarization in MEIC

    SciTech Connect (OSTI)

    Derbenev, Yaroslav; Lin, Fanglei; Morozov, Vasiliy; Zhang, Yuhong; Kondratenko, Anatoliy; Kondratenko, M A; Filatov, Yury

    2015-09-01

    Ion polarization in the Medium-energy Electron-Ion Collider (MEIC) is controlled by means of universal 3D spin rotators designed on the basis of "weak" solenoids. We use numerical calculations to demonstrate that the 3D rotators have negligible effect on the orbital properties of the ring. We present calculations of the polarization dynamics along the collider's orbit for both longitudinal and transverse polarization directions at a beam interaction point. We calculate the degree of depolarization due to the longitudinal and transverse beam emittances in case when the zero-integer spin resonance is compensated.

  10. Advanced numerical methods in mesh generation and mesh adaptation

    SciTech Connect (OSTI)

    Lipnikov, Konstantine; Danilov, A; Vassilevski, Y; Agonzal, A

    2010-01-01

    Numerical solution of partial differential equations requires appropriate meshes, efficient solvers and robust and reliable error estimates. Generation of high-quality meshes for complex engineering models is a non-trivial task. This task is made more difficult when the mesh has to be adapted to a problem solution. This article is focused on a synergistic approach to the mesh generation and mesh adaptation, where best properties of various mesh generation methods are combined to build efficiently simplicial meshes. First, the advancing front technique (AFT) is combined with the incremental Delaunay triangulation (DT) to build an initial mesh. Second, the metric-based mesh adaptation (MBA) method is employed to improve quality of the generated mesh and/or to adapt it to a problem solution. We demonstrate with numerical experiments that combination of all three methods is required for robust meshing of complex engineering models. The key to successful mesh generation is the high-quality of the triangles in the initial front. We use a black-box technique to improve surface meshes exported from an unattainable CAD system. The initial surface mesh is refined into a shape-regular triangulation which approximates the boundary with the same accuracy as the CAD mesh. The DT method adds robustness to the AFT. The resulting mesh is topologically correct but may contain a few slivers. The MBA uses seven local operations to modify the mesh topology. It improves significantly the mesh quality. The MBA method is also used to adapt the mesh to a problem solution to minimize computational resources required for solving the problem. The MBA has a solid theoretical background. In the first two experiments, we consider the convection-diffusion and elasticity problems. We demonstrate the optimal reduction rate of the discretization error on a sequence of adaptive strongly anisotropic meshes. The key element of the MBA method is construction of a tensor metric from hierarchical edge-based error estimates. We conclude that the quasi-optimal mesh must be quasi-uniform in this metric. All numerical experiments are based on the publicly available Ani3D package, the collection of advanced numerical instruments.

  11. Numerical simulation model for vertical flow in geothermal wells

    SciTech Connect (OSTI)

    Tachimori, M.

    1982-01-01

    A numerical simulation model for vertical flow in geothermal wells is presented. The model consists of equations for the conservation of mass, momentum, and energy, for thermodynamic state of water, for friction losses, for slip velocity relations, and of the criteria for various flow regimes. A new set of correlations and criteria is presented for two-phase flow to improve the accuracy of predictions; bubbly flow - Griffith and Wallis correlation, slug flow - Nicklin et al. one, annular-mist flow - Inoue and Aoki and modified by the author. The simulation method was verified by data from actual wells.

  12. Numerical modeling of an all vanadium redox flow battery.

    SciTech Connect (OSTI)

    Clausen, Jonathan R.; Brunini, Victor E.; Moffat, Harry K.; Martinez, Mario J.

    2014-01-01

    We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.

  13. Use of genomic data in risk assessment case study: I. Evaluation of the dibutyl phthalate male reproductive development toxicity data set

    SciTech Connect (OSTI)

    Makris, Susan L.; Euling, Susan Y.; Gray, L. Earl; Benson, Robert; Foster, Paul M.D.

    2013-09-15

    A case study was conducted, using dibutyl phthalate (DBP), to explore an approach to using toxicogenomic data in risk assessment. The toxicity and toxicogenomic data sets relative to DBP-related male reproductive developmental outcomes were considered conjointly to derive information about mode and mechanism of action. In this manuscript, we describe the case study evaluation of the toxicological database for DBP, focusing on identifying the full spectrum of male reproductive developmental effects. The data were assessed to 1) evaluate low dose and low incidence findings and 2) identify male reproductive toxicity endpoints without well-established modes of action (MOAs). These efforts led to the characterization of data gaps and research needs for the toxicity and toxicogenomic studies in a risk assessment context. Further, the identification of endpoints with unexplained MOAs in the toxicity data set was useful in the subsequent evaluation of the mechanistic information that the toxicogenomic data set evaluation could provide. The extensive analysis of the toxicology data set within the MOA context provided a resource of information for DBP in attempts to hypothesize MOAs (for endpoints without a well-established MOA) and to phenotypically anchor toxicogenomic and other mechanistic data both to toxicity endpoints and to available toxicogenomic data. This case study serves as an example of the steps that can be taken to develop a toxicological data source for a risk assessment, both in general and especially for risk assessments that include toxicogenomic data.

  14. SEQUESTRATION OF METALS IN ACTIVE CAP MATERIALS: A LABORATORY AND NUMERICAL EVALUATION

    SciTech Connect (OSTI)

    Dixon, K.; Knox, A.

    2012-02-13

    Active capping involves the use of capping materials that react with sediment contaminants to reduce their toxicity or bioavailability. Although several amendments have been proposed for use in active capping systems, little is known about their long-term ability to sequester metals. Recent research has shown that the active amendment apatite has potential application for metals contaminated sediments. The focus of this study was to evaluate the effectiveness of apatite in the sequestration of metal contaminants through the use of short-term laboratory column studies in conjunction with predictive, numerical modeling. A breakthrough column study was conducted using North Carolina apatite as the active amendment. Under saturated conditions, a spike solution containing elemental As, Cd, Co, Se, Pb, Zn, and a non-reactive tracer was injected into the column. A sand column was tested under similar conditions as a control. Effluent water samples were periodically collected from each column for chemical analysis. Relative to the non-reactive tracer, the breakthrough of each metal was substantially delayed by the apatite. Furthermore, breakthrough of each metal was substantially delayed by the apatite compared to the sand column. Finally, a simple 1-D, numerical model was created to qualitatively predict the long-term performance of apatite based on the findings from the column study. The results of the modeling showed that apatite could delay the breakthrough of some metals for hundreds of years under typical groundwater flow velocities.

  15. Numerical approach for the voloxidation process of an advanced spent fuel conditioning process (ACP)

    SciTech Connect (OSTI)

    Park, Byung Heung; Jeong, Sang Mun; Seo, Chung-Seok

    2007-07-01

    A voloxidation process is adopted as the first step of an advanced spent fuel conditioning process in order to prepare the SF oxide to be reduced in the following electrolytic reduction process. A semi-batch type voloxidizer was devised to transform a SF pellet into powder. In this work, a simple reactor model was developed for the purpose of correlating a gas phase flow rate with an operation time as a numerical approach. With an assumption that a solid phase and a gas phase are homogeneous in a reactor, a reaction rate for an oxidation was introduced into a mass balance equation. The developed equation can describe a change of an outlet's oxygen concentration including such a case that a gas flow is not sufficient enough to continue a reaction at its maximum reaction rate. (authors)

  16. Numerical simulation of fracture rocks and wave propagation by means of fractal theory

    SciTech Connect (OSTI)

    Valle G., R. del

    1994-12-31

    A numerical approach was developed for the dynamic simulation of fracture rocks and wave propagation. Based on some ideas of percolation theory and fractal growth, a network of particles and strings represent the rock model. To simulate an inhomogeneous medium, the particles and springs have random distributed elastic parameters and are implemented in the dynamic Navier equation. Some of the springs snap with criteria based on the confined stress applied, therefore creating a fractured rock consistent with the physical environment. The basic purpose of this research was to provide a method to construct a fractured rock with confined stress conditions as well as the wave propagation imposed in the model. Such models provide a better understanding of the behavior of wave propagation in fractured media. The synthetic seismic data obtained henceforth, can be used as a tool to develop methods for characterizing fractured rocks by means of geophysical inference.

  17. Development of a fast cyclotron gas stopper for intense rare isotope beams from projectile fragmentation: Study of ion extraction with a radiofrequency carpet

    SciTech Connect (OSTI)

    Bollen, Georg; Morrissey, David

    2011-01-16

    Research and development has been performed in support of the design of a future rare isotope beam facility in the US. An important aspect of plans for earlier RIA (Rare Isotope Accelerator) and a requirement of FRIB (Facility of Rare Isotope Beams) to be built at Michigan State University are the availability of so-called stopped beams for research that contributes to answering questions like how elements in the universe are created and to provide better insight into the nature of Fundamental Interactions. In order to create stopped beams techniques are required that transform fast rare isotopes beams as they are available directly after addresses questions like the origin of that will allow and High priority is given to the evaluation of intensity limitations and the efficiency of stopping of fast fragment beams in gas cells and to the exploration of options to increase the efficiency and the reduction of space charge effects. Systematic studies performed at MSU as part of the RIA R&D with a linear gas cell under conditions close to those expected at RIA and related simulations confirm that the efficiency of stopping and extracting ions decreases with increasing beam intensity. Similar results have also been observed at RIKEN in Japan. These results indicate the concepts presently under study will not be able to cover the full range of intensities of fast beams expected at RIA without major losses. The development of a more robust concept is therefore critical to the RIA concept. Recent new beam simulation studies performed at the NSCL show that the stopping of heavy ions in a weakly focusing gas-filled magnetic field can overcome the intensity limitation of present systems while simultaneously providing a much faster ion extraction. We propose to design and build such a cyclotron gas stopper and to test it at the NSCL under conditions as close as possible to those found at RIA.

  18. Numerical Simulations of Leakage from Underground LPG Storage Caverns

    SciTech Connect (OSTI)

    Yamamoto, Hajime; Pruess, Karsten

    2004-09-01

    To secure a stable supply of petroleum gas, underground storage caverns for liquified petroleum gas (LPG) are commonly used in many countries worldwide. Storing LPG in underground caverns requires that the surrounding rock mass remain saturated with groundwater and that the water pressure be higher than the liquid pressure inside the cavern. In previous studies, gas containment criteria for underground gas storage based on hydraulic gradient and pressure have been discussed, but these studies do not consider the physicochemical characteristics and behavior of LPG such as vaporization and dissolution in groundwater. Therefore, while these studies are very useful for designing storage caverns, they do not provide better understanding of the either the environmental effects of gas contamination or the behavior of vaporized LPG. In this study, we have performed three-phase fluid flow simulations of gas leakage from underground LPG storage caverns, using the multiphase multicomponent nonisothermal simulator TMVOC (Pruess and Battistelli, 2002), which is capable of solving the three-phase nonisothermal flow of water, gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. A two-dimensional cross-sectional model resembling an actual underground LPG facility in Japan was developed, and gas leakage phenomena were simulated for three different permeability models: (1) a homogeneous model, (2) a single-fault model, and (3) a heterogeneous model. In addition, the behavior of stored LPG was studied for the special case of a water curtain suddenly losing its function because of operational problems, or because of long-term effects such as clogging of boreholes. The results of the study indicate the following: (1) The water curtain system is a very powerful means for preventing gas leakage from underground storage facilities. By operating with appropriate pressure and layout, gas containment can be ensured. (2) However , in highly heterogeneous media such as fractured rock and fault zones, local flow paths within which the gas containment criterion is not satisfied could be formed. To eliminate such zones, treatments such as pre/post grouting or an additional installment of water-curtain boreholes are essential. (3) Along highly conductive features such as faults, even partially saturated zones possess certain effects that can retard or prevent gas leakage, while a fully unsaturated fault connected to the storage cavern can quickly cause a gas blowout. This possibility strongly suggests that ensuring water saturation of the rock surrounding the cavern is a very important requirement. (4) Even if an accident should suddenly impair the water curtain, the gas plume does not quickly penetrate the ground surface. In these simulations, the plume takes several months to reach the ground surface.

  19. A hybrid numerical fluid dynamics code for resistive magnetohydrodynamics

    SciTech Connect (OSTI)

    2006-04-01

    Spasmos is a computational fluid dynamics code that uses two numerical methods to solve the equations of resistive magnetohydrodynamic (MHD) flows in compressible, inviscid, conducting media[1]. The code is implemented as a set of libraries for the Python programming language[2]. It represents conducting and non-conducting gases and materials with uncomplicated (analytic) equations of state. It supports calculations in 1D, 2D, and 3D geometry, though only the 1D configuation has received significant testing to date. Because it uses the Python interpreter as a front end, users can easily write test programs to model systems with a variety of different numerical and physical parameters. Currently, the code includes 1D test programs for hydrodynamics (linear acoustic waves, the Sod weak shock[3], the Noh strong shock[4], the Sedov explosion[5], magnetic diffusion (decay of a magnetic pulse[6], a driven oscillatory "wine-cellar" problem[7], magnetic equilibrium), and magnetohydrodynamics (an advected magnetic pulse[8], linear MHD waves, a magnetized shock tube[9]). Spasmos current runs only in a serial configuration. In the future, it will use MPI for parallel computation.

  20. Numerical Model for Conduction-Cooled Current Lead Heat Loads

    SciTech Connect (OSTI)

    White, M.J.; Wang, X.L.; Brueck, H.D.; /DESY

    2011-06-10

    Current leads are utilized to deliver electrical power from a room temperature junction mounted on the vacuum vessel to a superconducting magnet located within the vacuum space of a cryostat. There are many types of current leads used at laboratories throughout the world; however, conduction-cooled current leads are often chosen for their simplicity and reliability. Conduction-cooled leads have the advantage of using common materials, have no superconducting/normal state transition, and have no boil-off vapor to collect. This paper presents a numerical model for conduction-cooled current lead heat loads. This model takes into account varying material and fluid thermal properties, varying thicknesses along the length of the lead, heat transfer in the circumferential and longitudinal directions, electrical power dissipation, and the effect of thermal intercepts. The model is validated by comparing the numerical model results to ideal cases where analytical equations are valid. In addition, the XFEL (X-Ray Free Electron Laser) prototype current leads are modeled and compared to the experimental results from testing at DESY's XFEL Magnet Test Stand (XMTS) and Cryomodule Test Bench (CMTB).

  1. A hybrid numerical fluid dynamics code for resistive magnetohydrodynamics

    Energy Science and Technology Software Center (OSTI)

    2006-04-01

    Spasmos is a computational fluid dynamics code that uses two numerical methods to solve the equations of resistive magnetohydrodynamic (MHD) flows in compressible, inviscid, conducting media[1]. The code is implemented as a set of libraries for the Python programming language[2]. It represents conducting and non-conducting gases and materials with uncomplicated (analytic) equations of state. It supports calculations in 1D, 2D, and 3D geometry, though only the 1D configuation has received significant testing to date. Becausemore » it uses the Python interpreter as a front end, users can easily write test programs to model systems with a variety of different numerical and physical parameters. Currently, the code includes 1D test programs for hydrodynamics (linear acoustic waves, the Sod weak shock[3], the Noh strong shock[4], the Sedov explosion[5], magnetic diffusion (decay of a magnetic pulse[6], a driven oscillatory "wine-cellar" problem[7], magnetic equilibrium), and magnetohydrodynamics (an advected magnetic pulse[8], linear MHD waves, a magnetized shock tube[9]). Spasmos current runs only in a serial configuration. In the future, it will use MPI for parallel computation.« less

  2. Numerical simulation of multi-layered textile composite reinforcement forming

    SciTech Connect (OSTI)

    Wang, P.; Hamila, N.; Boisse, P.

    2011-05-04

    One important perspective in aeronautics is to produce large, thick or/and complex structural composite parts. The forming stage presents an important role during the whole manufacturing process, especially for LCM processes (Liquid Composites Moulding) or CFRTP (Continuous Fibre Reinforcements and Thermoplastic resin). Numerical simulations corresponding to multi-layered composite forming allow the prediction for a successful process to produce the thick parts, and importantly, the positions of the fibres after forming to be known. This paper details a set of simulation examples carried out by using a semi-discrete shell finite element made up of unit woven cells. The internal virtual work is applied on all woven cells of the element taking into account tensions, in-plane shear and bending effects. As one key problem, the contact behaviours of tool/ply and ply/ply are described in the numerical model. The simulation results not only improve our understanding of the multi-layered composite forming process but also point out the importance of the fibre orientation and inter-ply friction during formability.

  3. On the numerical treatment of problems in atmospheric chemistry

    SciTech Connect (OSTI)

    Aro, C.J.

    1995-09-01

    Atmospheric chemical-radiative-transport (CRT) models are vital in performing research on atmospheric chemical change. Even with the enormous computing capability delivered by massively parallel systems, extended three dimensional CRT simulations are still not computationally feasible. The major obstacle in a CRT model is the nonlinear ODE system describing the chemical kinetics in the model. These ODE systems are usually very stiff and account for anywhere from 75% to 90% of the CPU time required to run a CRT model. In this study, a simple explicit class of time stepping method is developed and demonstrated to be useful in treating chemical ODE systems without the use of a Jacobian matrix. These methods, called preconditioned time differencing methods, are tested on small mathematically idealized problems, box model problems, and full 2-D and 3-D CRT models. The methods are found to be both fast and memory efficient. Studies are performed on both vector and parallel systems. The preconditioned time differencing methods are established as a viable alternative to the more common backward differentiation formulas in terms of CPU speed across architectural platforms.

  4. Numerical analysis of thermally assisted spin-transfer torque magnetization reversal in synthetic ferrimagnetic free layers

    SciTech Connect (OSTI)

    Shen, J.; Shi, M.; Tanaka, T. Matsuyama, K.

    2015-05-07

    The spin transfer torque magnetization reversal of synthetic ferrimagnetic free layers under pulsed temperature rise was numerically studied by solving the LandauLifshitzGilbert equation, taking into account the stochastic random fields, the temperature dependence of magnetic parameters, and the spin torque terms. The anti-parallel magnetization configuration was retained at the elevated temperature, due to interlayer dipole coupling. A significant thermal assistance effect, resulting in a 40% reduction in the switching current, was demonstrated during a nanosecond pulsed temperature rise up to 77% of the Curie temperature.

  5. Experimental Observations and Numerical Prediction of Induction Heating in a Graphite Test Article

    SciTech Connect (OSTI)

    Jankowski, Todd A [Los Alamos National Laboratory; Johnson, Debra P [Los Alamos National Laboratory; Jurney, James D [Los Alamos National Laboratory; Freer, Jerry E [Los Alamos National Laboratory; Dougherty, Lisa M [Los Alamos National Laboratory; Stout, Stephen A [Los Alamos National Laboratory

    2009-01-01

    The induction heating coils used in the plutonium casting furnaces at the Los Alamos National Laboratory are studied here. A cylindrical graphite test article has been built, instrumented with thermocouples, and heated in the induction coil that is normally used to preheat the molds during casting operations. Preliminary results of experiments aimed at understanding the induction heating process in the mold portion of the furnaces are reported. The experiments have been modeled in COMSOL Multiphysics and the numerical and experimental results are compared to one another. These comparisons provide insight into the heating process and provide a benchmark for COMSOL calculations of induction heating in the mold portion of the plutonium casting furnaces.

  6. The Ohio River Valley CO2 Storage Project AEP Mountaineer Plant, West Virginia Numerical Simulation and Risk Assessment Report

    SciTech Connect (OSTI)

    Neeraj Gupta

    2008-03-31

    A series of numerical simulations of carbon dioxide (CO{sub 2}) injection were conducted as part of a program to assess the potential for geologic sequestration in deep geologic reservoirs (the Rose Run and Copper Ridge formations), at the American Electric Power (AEP) Mountaineer Power Plant outside of New Haven, West Virginia. The simulations were executed using the H{sub 2}O-CO{sub 2}-NaCl operational mode of the Subsurface Transport Over Multiple Phases (STOMP) simulator (White and Oostrom, 2006). The objective of the Rose Run formation modeling was to predict CO{sub 2} injection rates using data from the core analysis conducted on the samples. A systematic screening procedure was applied to the Ohio River Valley CO{sub 2} storage site utilizing the Features, Elements, and Processes (FEP) database for geological storage of CO{sub 2} (Savage et al., 2004). The objective of the screening was to identify potential risk categories for the long-term geological storage of CO{sub 2} at the Mountaineer Power Plant in New Haven, West Virginia. Over 130 FEPs in seven main classes were assessed for the project based on site characterization information gathered in a geological background study, testing in a deep well drilled on the site, and general site conditions. In evaluating the database, it was apparent that many of the items were not applicable to the Mountaineer site based its geologic framework and environmental setting. Nine FEPs were identified for further consideration for the site. These FEPs generally fell into categories related to variations in subsurface geology, well completion materials, and the behavior of CO{sub 2} in the subsurface. Results from the screening were used to provide guidance on injection system design, developing a monitoring program, performing reservoir simulations, and other risk assessment efforts. Initial work indicates that the significant FEPs may be accounted for by focusing the storage program on these potential issues. The screening method was also useful in identifying unnecessary items that were not significant given the site-specific geology and proposed scale of the Ohio River Valley CO{sub 2} Storage Project. Overall, the FEP database approach provides a comprehensive methodology for assessing potential risk for a practical CO{sub 2} storage application. An integrated numerical fate and transport model was developed to enable risk and consequence assessment at field scale. Results show that such an integrated modeling effort would be helpful in meeting the project objectives (such as site characterization, engineering, permitting, monitoring and closure) during different stages. A reservoir-scale numerical model was extended further to develop an integrated assessment framework which can address the risk and consequence assessment, monitoring network design and permitting guidance needs. The method was used to simulate sequestration of CO{sub 2} in moderate quantities at the Mountaineer Power Plant. Results indicate that at the relatively low injection volumes planned for pilot scale demonstration at this site, the risks involved are minor to negligible, owing to a thick, low permeability caprock and overburden zones. Such integrated modeling approaches coupled with risk and consequence assessment modeling are valuable to project implementation, permitting, monitoring as well as site closure.

  7. Process Development and Basic Studies of Electrochemically Deposited CdTe-Based Solar Cells: Final Technical Report, 15 May 1998 - 17 August 2001

    SciTech Connect (OSTI)

    Kaydanov, V. I.; Ohno, T. R.

    2002-03-01

    This report describes the long-term research and development issues related to polycrystalline thin-film solar cells. Our general research approach is based on combining activities aimed at improvement of cell performance and stability with activities aimed at increasing our fundamental understanding of the properties of materials making up the cells: CdTe, CdS, multi-layer back-contact, and transparent conducting oxide (TCO) front-contact. We emphasize the relation between structural and electronic material properties and various processing procedures, as well as the microscopic mechanisms responsible for the cell performance and its degradation. There is a lack of knowledge and understanding of basic issues behind the CdTe/CdS cell performance and stability, such as the nature and electronic properties of impurities and defects that control the majority-carrier concentration, mechanisms of the dopant compensation, recombination centers, their nature and properties, diffusion, electro migration and transformation of defects under various processing, stress, and operating conditions. We believe that better basic understanding of the specific influence of polycrystallinity, especially for fine-grain materials characteristic of CdTe-based cells, is now one of the most important issues we must address. We need to clarify the role of grain boundaries in forming the film electronic properties, as well as those of the p-n junction. It is important to study and understand the influence of the grain boundaries on the spatial distribution and migration of impurities and electrically active defects. To fulfill these tasks, one needs to develop new methods and techniques (or adjust existing ones) for material characterization, as well as develop more sophisticated approaches to data analysis and modeling.

  8. Has anyone developed apps for the Green Button Initiative? |...

    Open Energy Info (EERE)

    > Groups > Developer Submitted by Ecpratt on 25 March, 2014 - 07:01 1 answer Points: 0 Hello- Yes There are numerous apps developed for use with the Green Button Initiative, you...

  9. A survey of numerical methods for shock physics applications

    SciTech Connect (OSTI)

    Hertel, E.S. Jr.

    1997-10-01

    Hydrocodes or more accurately, shock physics analysis packages, have been widely used in the US Department of Energy (DOE) laboratories and elsewhere around the world for over 30 years. Initial applications included weapons effects studies where the pressure levels were high enough to disregard the material strength, hence the term hydrocode. Over the last 30 years, Sandia has worked extensively to develop and apply advanced hydrocodes to armor/anti-armor interactions, warhead design, high explosive initiation, and nuclear weapon safety issues. The needs of the DOE have changed over the last 30 years, especially over the last decade. A much stronger emphasis is currently placed on the details of material deformation and high explosive initiation phenomena. The hydrocodes of 30 years ago have now evolved into sophisticated analysis tools that can replace testing in some situations and complement it in all situations. A brief history of the development of hydrocodes in the US will be given. The author also discusses and compares the four principal methods in use today for the solution of the conservation equations of mass, momentum, and energy for shock physics applications. The techniques discussed are the Eulerian methods currently employed by the Sandia multi-dimensional shock physics analysis package known as CTH; the element based Lagrangian method currently used by codes like DYNA; the element free Lagrangian method (also known as smooth particle hydrodynamics) used by codes like the Los Alamos code SPHINX; and the Arbitrary Lagrangian Eulerian methods used by codes like the Lawrence Livermore code CALE or the Sandia code ALEGRA.

  10. Numerical Modeling of Impact Initiation of High Explosives

    SciTech Connect (OSTI)

    Wu, C J; Piggott, T; Yoh, J; Reaugh, J

    2006-05-31

    We performed continuum mechanics simulations to examine the behavior of energetic materials in Ballistic Chamber Impact (BIC) experiments, using an Arbitrary Lagrangian-Eulerian code (ALE3D). Our simulations revealed that interface friction plays an important role in inducing the formation of shear bands, which result in 'hot spots' for ignition. The temperature localization during BIC impact was found to be significant in materials with high yield strength. In those materials, there are multiple locations inside shear bands can achieve temperatures exceeding the threshold temperature for reaction. In addition, we investigated the relevant parameters influencing the pressure profile of a BIC test by numerical analysis from a simple phenomenological model. To our surprise, we found that the peaks of BIC pressure profiles not only can be a result of multi-center chemical reactions, but can also arise from factors associated apparatus configuration.

  11. Three dimensional numerical simulations of the UPS-292-SC engine

    SciTech Connect (OSTI)

    O'Rourke, P.J.; Amsden, A.A.

    1987-01-01

    We present and analyze three-dimensional calculations of the spray, mixing and combustion in the UPS-292 stratified charge engine for three different operating conditions, corresponding to overall air-fuel ratios between 22.4 and 61.0. The numerical calculations are performed with KIVA, a multidimensional arbitrary-mesh, finite-difference hydrodynamics program for internal combustion engine applications. The calculations use a mesh of 10,000 computational cells, which conform to the shape of the piston bowl and cylinder and move to follow piston motion. Each operating condition is calculated from intake valve closure at 118/sup 0/ BTDC to 90/sup 0/ ATDC and requires approximately three hours of CRAY-XMP computer time.

  12. Numerical investigation of the double-arcing phenomenon in a cutting arc torch

    SciTech Connect (OSTI)

    Mancinelli, B. R.; Minotti, F. O.; Kelly, H.; Prevosto, L.

    2014-07-14

    A numerical investigation of the double-arcing phenomenon in a cutting arc torch is reported. The dynamics of the double-arcing were simulated by using a two-dimensional model of the gas breakdown development in the space-charge layer contiguous to the nozzle of a cutting arc torch operated with oxygen. The kinetic scheme includes ionization of heavy particles by electron impact, electron attachment, electron detachment, electronion recombination, and ionion recombination. Complementary measurements during double-arcing phenomena were also conducted. A marked rise of the nozzle voltage was found. The numerical results showed that the dynamics of a cathode spot at the exit of the nozzle inner surface play a key role in the raising of the nozzle voltage, which in turn allows more electrons to return to the wall at the nozzle inlet. The return flow of electrons thus closes the current loop of the double-arcing. The increase in the (floating) nozzle voltage is due to the fact that the increased electron emission at the spot is mainly compensated by the displacement current (the ions do not play a relevant role due to its low-mobility) until that the stationary state is achieved and the electron return flow fully-compensates the electron emission at the spot. A fairly good agreement was found between the model and the experiment for a spot emission current growth rate of the order of 7??10{sup 4}?A/s.

  13. An Implicit Algorithm for the Numerical Simulation of Shape-Memory Alloys

    SciTech Connect (OSTI)

    Becker, R; Stolken, J; Jannetti, C; Bassani, J

    2003-10-16

    Shape-memory alloys (SMA) have the potential to be used in a variety of interesting applications due to their unique properties of pseudoelasticity and the shape-memory effect. However, in order to design SMA devices efficiently, a physics-based constitutive model is required to accurately simulate the behavior of shape-memory alloys. The scope of this work is to extend the numerical capabilities of the SMA constitutive model developed by Jannetti et. al. (2003), to handle large-scale polycrystalline simulations. The constitutive model is implemented within the finite-element software ABAQUS/Standard using a user defined material subroutine, or UMAT. To improve the efficiency of the numerical simulations, so that polycrystalline specimens of shape-memory alloys can be modeled, a fully implicit algorithm has been implemented to integrate the constitutive equations. Using an implicit integration scheme increases the efficiency of the UMAT over the previously implemented explicit integration method by a factor of more than 100 for single crystal simulations.

  14. Developing Continuous SCM/CRM Forcing Using NWP Products Constrained...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    University of New York Stony Brook, New York Introduction This study examines the feasibility of using numerical weather prediction (NWP) model products to replace radiosondes...

  15. Transuranic decontamination of nitric acid solutions by the TRUEX solvent extraction process: preliminary development studies. [Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide

    SciTech Connect (OSTI)

    Vandegrift, G.F.; Leonard, R.A.; Steindler, M.J.; Horwitz, E.P.; Basile, L.J.; Diamond, H.; Kalina, D.G.; Kaplan, L.

    1984-07-01

    This report summarizes the work that has been performed to date at Argonne National Laboratory on the development of the TRUEX process, a solvent extraction process employing a bifunctional organophosphorous reagent in a PUREX process solvent (tributyl phosphate-normal paraffinic hydrocarbons). The purpose of this extraction process is to separate and concentrate transuranic (TRU) elements from nuclear waste. Assessments were made of the use of two TRUEX solvents: one incorporating the well-studied dihexyl-N,N-diethylcarbamoylmethylphosphonate (DHDECMP) and a second incorporating an extractant with superior properties for a 1M HNO/sub 3/ acid feed, octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (O/sub phi/D(IB)CMPO). In this report, conceptual flowsheets for the removal of soluble TRUs from high-level nuclear wastes using these two TRUEX proces solvents are presented, and flowsheet features are discussed in detail. The conceptual flowsheet for TRU-element removal from a PUREX waste by the O/sub phi/D(IB)CMPO-TRUEX process solvent was tested in a bench-scale countercurrent experiment, and results of that experiment are presented and discussed. The conclusion of this study is that the TRUEX process is able to separate TRUs from high-level wastes so that the major portion of the solid waste (approx. 99%) can be classified as non-TRU. Areas where more experimentation is needed are listed at the end of the report. 45 references, 17 figures, 56 tables.

  16. A neural approach for the numerical modeling of two-dimensional magnetic

    Office of Scientific and Technical Information (OSTI)

    hysteresis (Journal Article) | SciTech Connect A neural approach for the numerical modeling of two-dimensional magnetic hysteresis Citation Details In-Document Search Title: A neural approach for the numerical modeling of two-dimensional magnetic hysteresis This paper deals with a neural network approach to model magnetic hysteresis at macro-magnetic scale. Such approach to the problem seems promising in order to couple the numerical treatment of magnetic hysteresis to FEM numerical solvers

  17. NUMERICAL SIMULATIONS OF CHROMOSPHERIC ANEMONE JETS ASSOCIATED WITH MOVING MAGNETIC FEATURES

    SciTech Connect (OSTI)

    Yang, Liping; He, Jiansen; Tu, Chuanyi; Zhang, Lei; Peter, Hardi; Feng, Xueshang; Zhang, Shaohua

    2013-11-01

    Observations with the space-based solar observatory Hinode show that small-scale magnetic structures in the photosphere are found to be associated with a particular class of jets of plasma in the chromosphere called anemone jets. The goal of our study is to conduct a numerical experiment of such chromospheric anemone jets related to the moving magnetic features (MMFs). We construct a 2.5 dimensional numerical MHD model to describe the process of magnetic reconnection between the MMFs and the pre-existing ambient magnetic field, which is driven by the horizontal motion of the magnetic structure in the photosphere. We include thermal conduction parallel to the magnetic field and optically thin radiative losses in the corona to account for a self-consistent description of the evaporation process during the heating of the plasma due to the reconnection process. The motion of the MMFs leads to the expected jet and our numerical results can reproduce many observed characteristics of chromospheric anemone jets, topologically and quantitatively. As a result of the tearing instability, plasmoids are generated in the reconnection process that are consistent with the observed bright moving blobs in the anemone jets. An increase in the thermal pressure at the base of the jet is also driven by the reconnection, which induces a train of slow-mode shocks propagating upward. These shocks are a secondary effect, and only modulate the outflow of the anemone jet. The jet itself is driven by the energy input due to the reconnection of the MMFs and the ambient magnetic field.

  18. Final Technical Report: Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    SciTech Connect (OSTI)

    Schuster, Eugenio

    2014-05-02

    The strong coupling between the different physical variables involved in the plasma transport phenomenon and the high complexity of its dynamics call for a model-based, multivariable approach to profile control where those predictive models could be exploited. The overall objective of this project has been to extend the existing body of work by investigating numerically and experimentally active control of unstable fluctuations, including fully developed turbulence and the associated cross-field particle transport, via manipulation of flow profiles in a magnetized laboratory plasma device. Fluctuations and particle transport can be monitored by an array of electrostatic probes, and Ex#2;B flow profiles can be controlled via a set of biased concentric ring electrodes that terminate the plasma column. The goals of the proposed research have been threefold: i- to develop a predictive code to simulate plasma transport in the linear HELCAT (HELicon-CAThode) plasma device at the University of New Mexico (UNM), where the experimental component of the proposed research has been carried out; ii- to establish the feasibility of using advanced model-based control algorithms to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles, iii- to investigate the fundamental nonlinear dynamics of turbulence and transport physics. Lehigh University (LU), including Prof. Eugenio Schuster and one full-time graduate student, has been primarily responsible for control-oriented modeling and model-based control design. Undergraduate students have also participated in this project through the National Science Foundation Research Experience for Undergraduate (REU) program. The main goal of the LU Plasma Control Group has been to study the feasibility of controlling turbulence-driven transport by shaping the radial poloidal flow profile (i.e., by controlling flow shear) via biased concentric ring electrodes.

  19. Numerical Modeling At Coso Geothermal Area (2010) | Open Energy...

    Open Energy Info (EERE)

    model was developed using Poly3D to simulate the distribution and magnitude of stress concentration in the vicinity of the borehole floor, and determine the conditions...

  20. Analytical and numerical solution of one- and two-dimensional steady heat transfer in a coldplate

    SciTech Connect (OSTI)

    Jones, G.F.; Bennett, G.A.; Bultman, D.H.

    1987-01-01

    We develop analytical models for steady-state, one- and two-dimensional heat transfer in a single-material, flat-plate coldplate. Discrete heat sources are mounted on one side of the plate and heat transfer to a flowing fluid occurs on the other. The models are validated numerically using finite differences. We propose a simple procedure for estimating maximum coldplate temperature at the location of each heat source which includes thermal interaction among the sources. Results from one model are compared with data obtained for a composite coldplate operated in the laboratory. We demonstrate the utility of the models as diagnostic tools to be used for predicting the existence and extent of void volumes and delaminations in the composite material that can occur with coldplates of this type. Based on our findings, recommendations for effective coldplate design are given.

  1. Direct numerical simulation of turbulent flow in a rotating square duct

    SciTech Connect (OSTI)

    Dai, Yi-Jun; Huang, Wei-Xi Xu, Chun-Xiao; Cui, Gui-Xiang

    2015-06-15

    A fully developed turbulent flow in a rotating straight square duct is simulated by direct numerical simulations at Re{sub ?} = 300 and 0 ? Ro{sub ?} ? 40. The rotating axis is parallel to two opposite walls of the duct and normal to the main flow. Variations of the turbulence statistics with the rotation rate are presented, and a comparison with the rotating turbulent channel flow is discussed. Rich secondary flow patterns in the cross section are observed by varying the rotation rate. The appearance of a pair of additional vortices above the pressure wall is carefully examined, and the underlying mechanism is explained according to the budget analysis of the mean momentum equations.

  2. Numerical simulation of a thermoacoustic refrigerator. 2: Stratified flow around the stack

    SciTech Connect (OSTI)

    Worlikar, A.S.; Knio, O.M.; Klein, R.

    1998-08-10

    The unsteady, two-dimensional, thermally stratified flow in the neighborhood of an idealized thermoacoustic stack is analyzed using a low-Mach-number model that extends the adiabatic flow scheme developed in part 1 (Journal of Computational Physics 127, 424 (1996)). The extension consists of incorporation of numerical solvers for the energy equations in the fluid and the stack plates, and construction and implementation of fast Poisson solver for the velocity potential based on a domain decomposition/boundary Green`s function technique. The unsteady computations are used to predict the steady-state, acoustically generated temperature gradient across a two-dimensional couple and to analyze its dependence on the amplitude of the prevailing resonant wave. Computed results are compared to theoretical predictions and experimental data.

  3. NOx Sensor Development

    SciTech Connect (OSTI)

    Woo, L Y; Glass, R S

    2010-11-01

    NO{sub x} compounds, specifically NO and NO{sub 2}, are pollutants and potent greenhouse gases. Compact and inexpensive NO{sub x} sensors are necessary in the next generation of diesel (CIDI) automobiles to meet government emission requirements and enable the more rapid introduction of more efficient, higher fuel economy CIDI vehicles. Because the need for a NO{sub x} sensor is recent and the performance requirements are extremely challenging, most are still in the development phase. Currently, there is only one type of NO{sub x} sensor that is sold commercially, and it seems unlikely to meet more stringent future emission requirements. Automotive exhaust sensor development has focused on solid-state electrochemical technology, which has proven to be robust for in-situ operation in harsh, high-temperature environments (e.g., the oxygen stoichiometric sensor). Solid-state sensors typically rely on yttria-stabilized zirconia (YSZ) as the oxygen-ion conducting electrolyte and then target different types of metal or metal-oxide electrodes to optimize the response. Electrochemical sensors can be operated in different modes, including amperometric (a current is measured) and potentiometric (a voltage is measured), both of which employ direct current (dc) measurements. Amperometric operation is costly due to the electronics necessary to measure the small sensor signal (nanoampere current at ppm NO{sub x} levels), and cannot be easily improved to meet the future technical performance requirements. Potentiometric operation has not demonstrated enough promise in meeting long-term stability requirements, where the voltage signal drift is thought to be due to aging effects associated with electrically driven changes, both morphological and compositional, in the sensor. Our approach involves impedancemetric operation, which uses alternating current (ac) measurements at a specified frequency. The approach is described in detail in previous reports and several publications. Briefly, impedancemetric operation has shown the potential to overcome the drawbacks of other approaches, including higher sensitivity towards NO{sub x}, better long-term stability, potential for subtracting out background interferences, total NO{sub x} measurement, and lower cost materials and operation. Past LLNL research and development efforts have focused on characterizing different sensor materials and understanding complex sensing mechanisms. Continued effort has led to improved prototypes with better performance, including increased sensitivity (to less than 5 ppm) and long-term stability, with more appropriate designs for mass fabrication, including incorporation of an alumina substrate with an imbedded heater. Efforts in the last year to further improve sensor robustness have led to successful engine dynamometer testing with prototypes mounted directly in the engine manifold. Previous attempts had required exhaust gases to be routed into a separate furnace for testing due to mechanical failure of the sensor from engine vibrations. A more extensive cross-sensitivity study was also undertaken this last year to examine major noise factors including fluctuations in water, oxygen, and temperature. The quantitative data were then used to develop a strategy using numerical algorithms to improve sensor accuracy. The ultimate goal is the transfer of this technology to a supplier for commercialization. Due to the recent economic downturn, suppliers are demanding more comprehensive data and increased performance analysis before committing their resources to take the technology to market. Therefore, our NO{sub x} sensor work requires a level of technology development more thorough and extensive than ever before. The objectives are: (1) Develop an inexpensive, rapid-response, high-sensitivity and selective electrochemical sensor for oxides of nitrogen (NO{sub x}) for compression-ignition, direct-injection (CIDI) exhaust gas monitoring; (2) Explore and characterize novel, effective sensing methodologies based on impedance measurements and designs and manufacturing metho

  4. A 50-month gasifier mechanistic study and downstream unit process development program for the pressurized ash-agglomerating fluidized-bed gasification system

    SciTech Connect (OSTI)

    Haldipur, G.B.; Schmidt, D.K.; Smith, K.J.

    1989-03-01

    This technology development program scope included studies of those processes and components necessary to convert coal, oxidant and steam into a clean fuel gas. The configuration of the processes and components constitutes a Gasifier Island which is a key concept in the application of the KRW gasification and cleanup technologies. This Gasifier Island typically consists of process units that perform the following functions: feedstock preparation, gasification, desulfurization, heat recovery, particulate removal, and solid waste treatment. The processing has been conducted in a variety of gasifier operating modes including air-blown and oxygen-blown, both with and without in-bed desulfurization which includes injection of limestone or dolomite sorbent. Process configurations downstream of the gasifier have included recycle and non-recycle cyclones, sintered filters, and zinc ferrite fixed beds. Because of the developmental nature of the KRW technology program and the flexibility of the pilot plant itself, a wide range of gasifier-cleanup process configurations has been investigated. The KRW pilot plant program evaluated a system comprised of the following major process elements: gasifier and in-bed desulfurizer, particulate cleanup train, external sulfur polishing bed, and solid waste disposal system.

  5. Real time control and numerical simulation of pipeline subjected to landslide

    SciTech Connect (OSTI)

    Cuscuna, S.; Giusti, G.; Gramola, C.

    1984-06-01

    This paper describes SNAM research activity in the study of behaviour and real-time control of pipelines in landslide areas. The subject can be delt considering three different aspects: 1. Geotechnical characterization of unstable soils. The mechanical parameters of soil and the landslide types are defined; 2. Structural analysis of pipe-soil system. By means of a finite element program it's possible to study the pipe-soil interaction; in this numerical code the soil parameters attend by the non-linear elastic behaviour of pipe restraints. The results of this analysis are the location of the expected most stressed sections of pipe and the global behaviour of pipe inside the soil. 3. Instrumental control. The adoption of a suitable appliance of vibrating wire strain gauges allows the strain control of pipe in time. The aim is to make possible timely interventions in order to guarantee the installation safety.

  6. Numerical simulation of linear fiction welding (LFW) processes

    SciTech Connect (OSTI)

    Fratini, L.; La Spisa, D. [University of Palermo-Dept. of Industrial engineering (Italy)

    2011-05-04

    Solid state welding processes are becoming increasingly important due to a large number of advantages related to joining ''unweldable'' materials and in particular light weight alloys. Linear friction welding (LFW) has been used successfully to bond non-axisymmetric components of a range of materials including titanium alloys, steels, aluminum alloys, nickel, copper, and also dissimilar material combinations. The technique is useful in the research of quality of the joints and in reducing costs of components and parts of the aeronautic and automotive industries.LFW involves parts to be welded through the relative reciprocating motion of two components under an axial force. In such process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and proper bonding conditions due to both the temperature increase and the local pressure of the two edges to be welded. This paper is a comparative test between the numerical model in two dimensions, i.e. in plane strain conditions, and in three dimensions of a LFW process of AISI1045 steel specimens. It must be observed that the 3D model assures a faithful simulation of the actual threedimensional material flow, even if the two-dimensional simulation computational times are very short, a few hours instead of several ones as the 3D model. The obtained results were compared with experimental values found out in the scientific literature.

  7. Numeric spectral radiation hydrodynamic calculations of supernova shock breakouts

    SciTech Connect (OSTI)

    Sapir, Nir; Halbertal, Dorri

    2014-12-01

    We present here an efficient numerical scheme for solving the non-relativistic one-dimensional radiation-hydrodynamics equations including inelastic Compton scattering, which is not included in most codes and is crucial for solving problems such as shock breakout. The devised code is applied to the problems of a steady-state planar radiation mediated shock (RMS) and RMS breakout from a stellar envelope. The results are in agreement with those of a previous work on shock breakout, in which Compton equilibrium between matter and radiation was assumed and the 'effective photon' approximation was used to describe the radiation spectrum. In particular, we show that the luminosity and its temporal dependence, the peak temperature at breakout, and the universal shape of the spectral fluence derived in this earlier work are all accurate. Although there is a discrepancy between the spectral calculations and the effective photon approximation due to the inaccuracy of the effective photon approximation estimate of the effective photon production rate, which grows with lower densities and higher velocities, the difference in peak temperature reaches only 30% for the most discrepant cases of fast shocks in blue supergiants. The presented model is exemplified by calculations for supernova 1987A, showing the detailed evolution of the burst spectrum. The incompatibility of the stellar envelope shock breakout model results with observed properties of X-ray flashes (XRFs) and the discrepancy between the predicted and observed rates of XRFs remain unexplained.

  8. Process development of thin strip steel casting

    SciTech Connect (OSTI)

    Sussman, R.C.; Williams, R.S.

    1990-12-01

    An important new frontier is being opened in steel processing with the emergence of thin strip casting. Casting steel directly to thin strip has enormous benefits in energy savings by potentially eliminating the need for hot reduction in a hot strip mill. This has been the driving force for numerous current research efforts into the direct strip casting of steel. The US Department of Energy initiated a program to evaluate the development of thin strip casting in the steel industry. In earlier phases of this program, planar flow casting on an experimental caster was studied by a team of engineers from Westinghouse Electric corporation and Armco Inc. A subsequent research program was designed as a fundamental and developmental study of both planar and melt overflow casting processes. This study was arranged as several separate and distinct tasks which were often completed by different teams of researchers. An early task was to design and build a water model to study fluid flow through different designs of planar flow casting nozzles. Another important task was mathematically modeling of melt overflow casting process. A mathematical solidification model for the formation of the strip in the melt overflow process was written. A study of the material and conditioning of casting substrates was made on the small wheel caster using the melt overflow casting process. This report discusses work on the development of thin steel casting.

  9. A numerical investigation of transonic axial compressor rotor flow using a low-Reynolds-number {kappa}-{epsilon} turbulence model

    SciTech Connect (OSTI)

    Arima, T.; Sonoda, T.; Shirotori, M.; Tamura, A.; Kikuchi, K.

    1999-01-01

    The authors have developed a computer simulation code for three-dimensional viscous flow in turbomachinery based on the time-averaged compressible Navier-Stokes equations and a low-Reynolds-number {kappa}-{epsilon} turbulence model. It is described in detail in this paper. The code is used to compute the flow fields for two types of rotor (a transonic fan NASA Rotor 67 and a transonic axial compressor NASA rotor 37), and numerical results are compared to experimental data based on aerodynamic probe and laser anemometer measurements. In the case of Rotor 67, calculated and experimental results are compared under the design speed to validate the code. The calculated results show good agreement with the experimental data, such as the rotor performance map and the spanwise distribution of total pressure, total temperature, and flow angle downstream of the rotor. In the case of Rotor 37, detailed comparisons between the numerical results and the experimental data are made under the design speed condition to assess the overall quality of the numerical solution. Furthermore, comparisons under the part-speed condition are used to investigate a flow field without passage shock. The results are well predicted qualitatively. However, considerable quantitative discrepancies remain in predicting the flow near the tip. In order to assess the predictive capabilities of the developed code, computed flow structures are presented with the experimental data for each rotor and the cause of the discrepancies is discussed.

  10. Direct Numerical Simulations of Autoignition in Stratified Dimethyl-ether (DME)/Air Turbulent Mixtures

    SciTech Connect (OSTI)

    Bansal, Gaurav; Mascarenhas, Ajith; Chen, Jacqueline H.

    2014-10-01

    In our paper, two- and three-dimensional direct numerical simulations (DNS) of autoignition phenomena in stratified dimethyl-ether (DME)/air turbulent mixtures are performed. A reduced DME oxidation mechanism, which was obtained using rigorous mathematical reduction and stiffness removal procedure from a detailed DME mechanism with 55 species, is used in the present DNS. The reduced DME mechanism consists of 30 chemical species. This study investigates the fundamental aspects of turbulence-mixing-autoignition interaction occurring in homogeneous charge compression ignition (HCCI) engine environments. A homogeneous isotropic turbulence spectrum is used to initialize the velocity field in the domain. Moreover, the computational configuration corresponds to a constant volume combustion vessel with inert mass source terms added to the governing equations to mimic the pressure rise due to piston motion, as present in practical engines. DME autoignition is found to be a complex three-staged process; each stage corresponds to a distinct chemical kinetic pathway. The distinct role of turbulence and reaction in generating scalar gradients and hence promoting molecular transport processes are investigated. Then, by applying numerical diagnostic techniques, the different heat release modes present in the igniting mixture are identified. In particular, the contribution of homogeneous autoignition, spontaneous ignition front propagation, and premixed deflagration towards the total heat release are quantified.

  11. Sensitivity of injection costs to input petrophysical parameters in numerical geologic carbon sequestration models

    SciTech Connect (OSTI)

    Cheng, C. L.; Gragg, M. J.; Perfect, E.; White, Mark D.; Lemiszki, P. J.; McKay, L. D.

    2013-08-24

    Numerical simulations are widely used in feasibility studies for geologic carbon sequestration. Accurate estimates of petrophysical parameters are needed as inputs for these simulations. However, relatively few experimental values are available for CO2-brine systems. Hence, a sensitivity analysis was performed using the STOMP numerical code for supercritical CO2 injected into a model confined deep saline aquifer. The intrinsic permeability, porosity, pore compressibility, and capillary pressure-saturation/relative permeability parameters (residual liquid saturation, residual gas saturation, and van Genuchten alpha and m values) were varied independently. Their influence on CO2 injection rates and costs were determined and the parameters were ranked based on normalized coefficients of variation. The simulations resulted in differences of up to tens of millions of dollars over the life of the project (i.e., the time taken to inject 10.8 million metric tons of CO2). The two most influential parameters were the intrinsic permeability and the van Genuchten m value. Two other parameters, the residual gas saturation and the residual liquid saturation, ranked above the porosity. These results highlight the need for accurate estimates of capillary pressure-saturation/relative permeability parameters for geologic carbon sequestration simulations in addition to measurements of porosity and intrinsic permeability.

  12. Direct Numerical Simulations of Autoignition in Stratified Dimethyl-ether (DME)/Air Turbulent Mixtures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bansal, Gaurav; Mascarenhas, Ajith; Chen, Jacqueline H.

    2014-10-01

    In our paper, two- and three-dimensional direct numerical simulations (DNS) of autoignition phenomena in stratified dimethyl-ether (DME)/air turbulent mixtures are performed. A reduced DME oxidation mechanism, which was obtained using rigorous mathematical reduction and stiffness removal procedure from a detailed DME mechanism with 55 species, is used in the present DNS. The reduced DME mechanism consists of 30 chemical species. This study investigates the fundamental aspects of turbulence-mixing-autoignition interaction occurring in homogeneous charge compression ignition (HCCI) engine environments. A homogeneous isotropic turbulence spectrum is used to initialize the velocity field in the domain. Moreover, the computational configuration corresponds to amore » constant volume combustion vessel with inert mass source terms added to the governing equations to mimic the pressure rise due to piston motion, as present in practical engines. DME autoignition is found to be a complex three-staged process; each stage corresponds to a distinct chemical kinetic pathway. The distinct role of turbulence and reaction in generating scalar gradients and hence promoting molecular transport processes are investigated. Then, by applying numerical diagnostic techniques, the different heat release modes present in the igniting mixture are identified. In particular, the contribution of homogeneous autoignition, spontaneous ignition front propagation, and premixed deflagration towards the total heat release are quantified.« less

  13. Numerical studies of fluid-rock interactions in EnhancedGeothermal...

    Office of Scientific and Technical Information (OSTI)

    rates of heat extraction, and can offer geologic storage of carbon as an ancillary benefit. Fluid-rock interactions ... reservoir zone with anhydrous supercritical COsub 2. ...

  14. A numerical study on bow shocks around the lightning return stroke channel

    SciTech Connect (OSTI)

    Chen, Qiang Chen, Bin Yi, Yun; Chen, P. F.; Mao, Yunfei; Xiong, Run

    2015-03-15

    Bow shock structures are important to various hydrodynamics and magnetohydrodynamics (MHD) phenomena in geophysics and astrophysics. The formation and propagation of bow shocks around the lightning return stroke channel are investigated based on the self-similar motion theory and simulated with a two-dimensional Eulerian finite volume resistive radiation MHD code. In this framework, as verification of theoretical models, the evolving structures of many quantities, such as the plasma density, temperature, pressure, shock velocity, and magnetic field, can be obtained, which present all the characteristics of bow shocks in the lightning return stroke processes. The evolution characteristics and the configuration of the curved return stroke channels, e.g., the non-ideal effects and the scaling laws, are discussed in detail. The results may have applications for some observed features of the return stroke channels and other phenomena in the lightning discharge plasmas.

  15. Studies of the steam generator degraded tubes behavior on BRUTUS test loop

    SciTech Connect (OSTI)

    Chedeau, C.; Rassineux, B.

    1997-04-01

    Studies for the evaluation of steam generator tube bundle cracks in PWR power plants are described. Global tests of crack leak rates and numerical calculations of crack opening area are discussed in some detail. A brief overview of thermohydraulic studies and the development of a mechanical probabilistic design code is also given. The COMPROMIS computer code was used in the studies to quantify the influence of in-service inspections and maintenance work on the risk of a steam generator tube rupture.

  16. Numerical techniques for steady two-dimensional transcritical stratified flow problems, with an application to the intermediate field dynamics of Ocean Thermal Energy Conversion plants

    SciTech Connect (OSTI)

    Jones, J.M.; Jirka, G.H.; Caughey, D.A.

    1985-01-01

    The development of predictive techniques for the predominantly horizontal, layered fluid motions that result when a continuous buoyant source is discharged into an ambient fluid at a bounding surface, interface or equilibrium level is studied. Although the numerical techniques developed are applicable to general discharge configurations, the model development is focused on the particular case of a radial source of buoyancy and momentum discharged into a uniform ambient crossflow. The resulting density current is analyzed by application of the depth-integrated hydrodynamic equations. The density current dynamics are shown to vary with the relative intermediate- to near-field strengths, as characterized by the ratio of their respective length scales. The complete range of this interaction, from small near-field effects to large near-field effects, is investigated. Results are presented as the depth integrated velocity and current thickness distributions for different field strength values. The model predictions are compared to two sets of laboratory data and to limited field information, involving a river discharge and a submerged outfall into the ocean. Good agreement is obtained in all cases. Finally, the model results are applied to the prediction of a river plume into a coastal ocean current and to the continuous discharge from an OTEC plant operating in the stratified ocean. In both cases, the results indicate the significant horizontal extent (order of several kilometers) of the resulting current, together with their limited vertical extent (order of several meters). Their strong sensitivity to ambient current magnitude and stratification strength is demonstrated.

  17. Numerical Modeling At Dixie Valley Geothermal Area (Benoit, 1999...

    Open Energy Info (EERE)

    large geothermal flow test was performed where there was 6 geothermal wells flowing at once and 8 idle wells being monitored. The conceptual model developed from this flow test...

  18. Numerical Modeling of the Nucleation Conditions of Petal-Centerline...

    Open Energy Info (EERE)

    model using Poly3D has been developed to investigate the conditions in which the stress concentration below the floor of a borehole can cause tensile stress necessary to...

  19. Assembly of 500,000 inter-specific catfish expressed sequence tags and large scale gene-associated marker development for whole genome association studies

    SciTech Connect (OSTI)

    Catfish Genome Consortium; Wang, Shaolin; Peatman, Eric; Abernathy, Jason; Waldbieser, Geoff; Lindquist, Erika; Richardson, Paul; Lucas, Susan; Wang, Mei; Li, Ping; Thimmapuram, Jyothi; Liu, Lei; Vullaganti, Deepika; Kucuktas, Huseyin; Murdock, Christopher; Small, Brian C; Wilson, Melanie; Liu, Hong; Jiang, Yanliang; Lee, Yoona; Chen, Fei; Lu, Jianguo; Wang, Wenqi; Xu, Peng; Somridhivej, Benjaporn; Baoprasertkul, Puttharat; Quilang, Jonas; Sha, Zhenxia; Bao, Baolong; Wang, Yaping; Wang, Qun; Takano, Tomokazu; Nandi, Samiran; Liu, Shikai; Wong, Lilian; Kaltenboeck, Ludmilla; Quiniou, Sylvie; Bengten, Eva; Miller, Norman; Trant, John; Rokhsar, Daniel; Liu, Zhanjiang

    2010-03-23

    Background-Through the Community Sequencing Program, a catfish EST sequencing project was carried out through a collaboration between the catfish research community and the Department of Energy's Joint Genome Institute. Prior to this project, only a limited EST resource from catfish was available for the purpose of SNP identification. Results-A total of 438,321 quality ESTs were generated from 8 channel catfish (Ictalurus punctatus) and 4 blue catfish (Ictalurus furcatus) libraries, bringing the number of catfish ESTs to nearly 500,000. Assembly of all catfish ESTs resulted in 45,306 contigs and 66,272 singletons. Over 35percent of the unique sequences had significant similarities to known genes, allowing the identification of 14,776 unique genes in catfish. Over 300,000 putative SNPs have been identified, of which approximately 48,000 are high-quality SNPs identified from contigs with at least four sequences and the minor allele presence of at least two sequences in the contig. The EST resource should be valuable for identification of microsatellites, genome annotation, large-scale expression analysis, and comparative genome analysis. Conclusions-This project generated a large EST resource for catfish that captured the majority of the catfish transcriptome. The parallel analysis of ESTs from two closely related Ictalurid catfishes should also provide powerful means for the evaluation of ancient and recent gene duplications, and for the development of high-density microarrays in catfish. The inter- and intra-specific SNPs identified from all catfish EST dataset assembly will greatly benefit the catfish introgression breeding program and whole genome association studies.

  20. Development of high-spatial and high-mass resolution mass spectrometric imaging (MSI) and its application to the study of small metabolites and endogenous molecules of plants

    SciTech Connect (OSTI)

    Jun, Ji Hyun

    2011-11-30

    High-spatial and high-mass resolution laser desorption ionization (LDI) mass spectrometric (MS) imaging technology was developed for the attainment of MS images of higher quality containing more information on the relevant cellular and molecular biology in unprecedented depth. The distribution of plant metabolites is asymmetric throughout the cells and tissues, and therefore the increase in the spatial resolution was pursued to reveal the localization of plant metabolites at the cellular level by MS imaging. For achieving high-spatial resolution, the laser beam size was reduced by utilizing an optical fiber with small core diameter (25 μm) in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer. Matrix application was greatly improved using oscillating capillary nebulizer. As a result, single cell level spatial resolution of ~ 12 μm was achieved. MS imaging at this high spatial resolution was directly applied to a whole Arabidopsis flower and the substructures of an anther and single pollen grains at the stigma and anther were successfully visualized. MS imaging of high spatial resolution was also demonstrated to the secondary roots of Arabidopsis thaliana and a high degree of localization of detected metabolites was successfully unveiled. This was the first MS imaging on the root for molecular species. MS imaging with high mass resolution was also achieved by utilizing the LTQ-Orbitrap mass spectrometer for the direct identification of the surface metabolites on the Arabidopsis stem and root and differentiation of isobaric ions having the same nominal mass with no need of tandem mass spectrometry (MS/MS). MS imaging at high-spatial and high-mass resolution was also applied to cer1 mutant of the model system Arabidopsis thaliana to demonstrate its usefulness in biological studies and reveal associated metabolite changes in terms of spatial distribution and/or abundances compared to those of wild-type. The spatial distribution of targeted metabolites, mainly waxes and flavonoids, was systematically explored on various organs, including flowers, leaves, stems, and roots at high spatial resolution of ~ 12-50 μm and the changes in the abundance level of these metabolites were monitored on the cer1 mutant with respect to the wild-type. This study revealed the metabolic biology of CER1 gene on each individual organ level with very detailed high spatial resolution. The separate MS images of isobaric metabolites, i.e. C29 alkane vs. C28 aldehyde could be constructed on both genotypes from MS imaging at high mass resolution. This allows tracking of abundance changes for those compounds along with the genetic mutation, which is not achievable with low mass resolution mass spectrometry. This study supported previous hypothesis of molecular function of CER1 gene as aldehyde decarbonylase, especially by displaying hyper accumulation of aldehydes and C30 fatty acid and decrease in abundance of alkanes and ketones in several plant organs of cer1 mutant. The scope of analytes was further directed toward internal cell metabolites from the surface metabolites of the plant. MS profiling and imaging of internal cell metabolites were performed on the vibratome section of Arabidopsis leaf. Vibratome sectioning of the leaf was first conducted to remove the surface cuticle layer and it was followed by enzymatic treatment of the section to induce the digestion of primary cell walls, middle lamella, and expose the internal cells underneath to the surface for detection with the laser by LDI-MS. The subsequent MS imaging onto the enzymatically treated vibratome section allowed us to map the distribution of the metabolites in the internal cell layers, linolenic acid (C18:3 FA) and linoleic acid (C18:2 FA). The development of an assay for relative quantification of analytes at the single subcellular/organelle level by LDI-MS imaging was attempted and both plausibility and significant obstacles were seen. As a test system, native plant organelle, chloroplasts isolated from the spinach leaves were used and the localization of isolated chloroplasts dispersed on the target plate in low density was monitored by detecting the ion signal of chlorophyll a (Chl a) degradation products such as pheophytin a and pheophobide a by LDI-MS imaging in combination with fluorescence microscopy. The number of chloroplasts and their localization visualized in the MS image exactly matched those in the fluorescence image especially at low density, which first shows the plausibility of single-organelle level quantification of analytes by LDI-MS. The accumulation level of Chl a within a single chloroplast detected by LDI-MS was compared to the fluorescence signal on a pixel-to-pixel basis to further confirm the correlations of the accumulation levels measured by two methods. The proportional correlation was observed only for the chloroplasts which do not show the significant leakage of chlorophyll indicated by MS ion signal of Chl a degradation products and fluorescence signal, which was presumably caused by the prior fluorescence measurement before MS imaging. Further investigation is necessary to make this method more complete and develop LDI-MS imaging as an effective analytical tool to evaluate a relative accumulation of analytes of interest at the single subcellular/organelle level.

  1. A STUDY ON GEOTHERMAL RESERVOIR ENGlNEERING APPROACH COMBINED WITH GEOLOGICAL INFORMATIONS

    SciTech Connect (OSTI)

    Hirakawa, S.; Yamaguchi, S.; Yoshinobu, F.

    1985-01-22

    This paper presents the combined approaches of reservoir geology and engineering to a geothermal field where geological characteristics are highly complex and heterogeneous.Especially,the concrete approaches are discussed for the case of geothermal reservoir performance studies with a developed numerical model, by showing example cases accompanied with reinjection of produced disposal hot water into underground in an object geothermal reservoir. This combined approach will be a great help in solving complicated problems encountered during the development of a geothermal field.

  2. Validation of Numerical Two-Fluid and Kinetic Plasma Models

    SciTech Connect (OSTI)

    Daniel Barnes

    2011-03-25

    This was a four year grant commencing October 1, 2003 and finishing September 30, 2007. The funding was primarily used to support the work of the Principal Investigator, who collaborated with Profs. Scott Parker and John Cary at U. Colorado, and with two students, N. Xiang and J. Cheng also of U. Colorado. The technical accomplishments of this grant can be found in the publications listed in the final Section here. The main accomplishments of the grant work were: (1) Development and implementation of time-implicit two-fluid simulation methods in collaboration with the NIMROD team; and (2) Development and testing of a new time-implicit delta-f, energy-conserving method The basic two-fluid method, with many improvements is used in present NIMROD calculations. The energy-conserving delta-f method is under continuing development under contract between Coronado Consulting, a New Mexico sole proprietorship and the Oak Ridge National Laboratory.

  3. Experimental and numerical investigation of hydrogen combustion in a supersonic flow

    SciTech Connect (OSTI)

    Segal, C.

    1991-01-01

    Supersonic combustion ramjet, or SCRAMJET, engines are currently being evaluated for the propulsion of hypersonic vehicles. A unique supersonic wind tunnel facility has been built at the Aerospace Research Laboratory to simulate the operation of a SCRAMJET over a range of Mach numbers of 5 to 6.5 and altitudes of 40,000 to 150,000 ft. The tunnel provides high stagnation temperature, clean air in a continuous Mach 2 flow to the combustor where hydrogen is injected and burned. One of the major parameters in the design of the engine is the combustion efficiency, a quantity which is extremely difficult to evaluate directly. Wall pressure and temperature measurements were made on a model combustor in the ARL facility and a one-dimensional, chemical equilibrium, finite difference model was used to infer combustion efficiency. The initial stagnation temperature was maintained around or below 850 K and an inlet static pressure of 1/2 atm, or less. At these relative low temperatures, thermal choking occurred for relatively low equivalence ratios, limiting this parameter to a maximum of 0.1, depending on the injection configuration. A detailed validation of the analytical model requires extensive knowledge of the physical properties of the flowfield. Since reliable, non-intrusive measurements methods are still under development, the results of the combustion efficiency evaluation were compared with a detailed numerical simulation of the flowfield of interest. The numerical simulation used a 3-D full Navier-Stokes program, which includes a finite rate chemistry model to duplicate one of the experimental cases. The calculations were performed on a CRAY - 2S supercomputer at the National Supercomputer Applications Center at NASA Langley. The solution required 35 CPU hours.

  4. Ocean current wave interaction study

    SciTech Connect (OSTI)

    Hayes, J.G.

    1980-09-20

    A numerical model has been developed to incorporate refraction of ocean surface gravity waves by major ocean currents. The model is initialized with directional wave spectra and verified with aircraft synthetic aperture radar X band spectra, laser profilometer spectra, and pitch and roll buoy data. Data collected during the Marineland test experiment are used as surface truth observations for the wave-current study. Evidence of Gulf Stream refraction and trapping of surface waves as well as caustics in the current is shown and modeled assuming a nonuniform Gulf Stream distribution. Frequency and directional resolution of the wave spectral distribution and the current refraction patterns illustrates the need for further study of ocean current-wave interaction in wave refraction studies.

  5. Numerical simulation of jet mixing concepts in Tank 241-SY-101

    SciTech Connect (OSTI)

    Trent, D.S.; Michener, T.E.

    1993-03-01

    The episodic gas release events (GRES) that have characterized the behavior of Tank 241-SY-101 for the past several years are thought to result from gases generated by the waste material in it that become trapped in the layer of settled solids at the bottom of the tank. Several concepts for mitigating the GREs have been proposed. One concept involves mobilizing the solid particles with mixing jets. The rationale behind this idea is to prevent formation of a consolidated layer of settled solids at the bottom of the tank, thus inhibiting the accumulation of gas bubbles in this layer. Numerical simulations were conducted using the TEMPEST computer code to assess the viability and effectiveness of the proposed jet discharge concepts and operating parameters. Before these parametric studies were commenced, a series of turbulent jet studies were conducted that established the adequacy of the TEMPEST code for this application. Configurations studied for Tank 241-SY-101 include centrally located downward discharging jets, draft tubes, and horizontal jets that are either stationary or rotating. Parameter studies included varying the jet discharge velocity, jet diameter, discharge elevation, and material properties. A total of 18 simulations were conducted and are reported in this document. The effect of gas bubbles on the mixing dynamics was not included within the scope of this study.

  6. Numerical Optimization Algorithms and Software for Systems Biology

    SciTech Connect (OSTI)

    Saunders, Michael

    2013-02-02

    The basic aims of this work are: to develop reliable algorithms for solving optimization problems involving large stoi- chiometric matrices; to investigate cyclic dependency between metabolic and macromolecular biosynthetic networks; and to quantify the significance of thermodynamic constraints on prokaryotic metabolism.

  7. Numerical method to test a theoretical model of the quantum interferen...

    Office of Scientific and Technical Information (OSTI)

    A numerical method is provided to fit the experimental conductivity to the complicated conductivity expression for the quantum interference effect of Anderson localization. This ...

  8. Numerical calculation of protein-ligand binding rates through solution of the Smoluchowski equation using smoothed particle hydrodynamics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pan, Wenxiao; Daily, Michael; Baker, Nathan A.

    2015-05-07

    Background: The calculation of diffusion-controlled ligand binding rates is important for understanding enzyme mechanisms as well as designing enzyme inhibitors. Methods: We demonstrate the accuracy and effectiveness of a Lagrangian particle-based method, smoothed particle hydrodynamics (SPH), to study diffusion in biomolecular systems by numerically solving the time-dependent Smoluchowski equation for continuum diffusion. Unlike previous studies, a reactive Robin boundary condition (BC), rather than the absolute absorbing (Dirichlet) BC, is considered on the reactive boundaries. This new BC treatment allows for the analysis of enzymes with “imperfect” reaction rates. Results: The numerical method is first verified in simple systems and thenmore » applied to the calculation of ligand binding to a mouse acetylcholinesterase (mAChE) monomer. Rates for inhibitor binding to mAChE are calculated at various ionic strengths and compared with experiment and other numerical methods. We find that imposition of the Robin BC improves agreement between calculated and experimental reaction rates. Conclusions: Although this initial application focuses on a single monomer system, our new method provides a framework to explore broader applications of SPH in larger-scale biomolecular complexes by taking advantage of its Lagrangian particle-based nature.« less

  9. Numerical calculation of protein-ligand binding rates through solution of the Smoluchowski equation using smooth particle hydrodynamics

    SciTech Connect (OSTI)

    Pan, Wenxiao; Daily, Michael D.; Baker, Nathan A.

    2015-12-01

    We demonstrate the accuracy and effectiveness of a Lagrangian particle-based method, smoothed particle hydrodynamics (SPH), to study diffusion in biomolecular systems by numerically solving the time-dependent Smoluchowski equation for continuum diffusion. The numerical method is first verified in simple systems and then applied to the calculation of ligand binding to an acetylcholinesterase monomer. Unlike previous studies, a reactive Robin boundary condition (BC), rather than the absolute absorbing (Dirichlet) boundary condition, is considered on the reactive boundaries. This new boundary condition treatment allows for the analysis of enzymes with "imperfect" reaction rates. Rates for inhibitor binding to mAChE are calculated at various ionic strengths and compared with experiment and other numerical methods. We find that imposition of the Robin BC improves agreement between calculated and experimental reaction rates. Although this initial application focuses on a single monomer system, our new method provides a framework to explore broader applications of SPH in larger-scale biomolecular complexes by taking advantage of its Lagrangian particle-based nature.

  10. Numerical calculation of protein-ligand binding rates through solution of the Smoluchowski equation using smoothed particle hydrodynamics

    SciTech Connect (OSTI)

    Pan, Wenxiao; Daily, Michael; Baker, Nathan A.

    2015-05-07

    Background: The calculation of diffusion-controlled ligand binding rates is important for understanding enzyme mechanisms as well as designing enzyme inhibitors. Methods: We demonstrate the accuracy and effectiveness of a Lagrangian particle-based method, smoothed particle hydrodynamics (SPH), to study diffusion in biomolecular systems by numerically solving the time-dependent Smoluchowski equation for continuum diffusion. Unlike previous studies, a reactive Robin boundary condition (BC), rather than the absolute absorbing (Dirichlet) BC, is considered on the reactive boundaries. This new BC treatment allows for the analysis of enzymes with imperfect reaction rates. Results: The numerical method is first verified in simple systems and then applied to the calculation of ligand binding to a mouse acetylcholinesterase (mAChE) monomer. Rates for inhibitor binding to mAChE are calculated at various ionic strengths and compared with experiment and other numerical methods. We find that imposition of the Robin BC improves agreement between calculated and experimental reaction rates. Conclusions: Although this initial application focuses on a single monomer system, our new method provides a framework to explore broader applications of SPH in larger-scale biomolecular complexes by taking advantage of its Lagrangian particle-based nature.

  11. Economic Development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Economic Development Economic Development Los Alamos is committed to investing and partnering in economic development initiatives and programs that have a positive impact to stimulate business growth that creates jobs and strengthens communities in Northern New Mexico. September 20, 2013 LANS Venture Acceleration Fund (VAF) award enabled Ideum to develop motion recognition software for international release. Jim Spadaccini (R) has tapped into the Lab's economic development programs: VAF, NMSBA,

  12. Building a programmable interface for physics codes using numeric python

    SciTech Connect (OSTI)

    Yang, T.-Y.B.; Dubois, P.F.; Motteler, Z.C.

    1996-04-16

    With its portability, ease to add built-in functions and objects in C, and fast array facility among many other features, Python proved to be an excellent language for creating programmable scientific applications. In addition to the two modules presented, there are also other progresses at LLNL in using Python. For example, Python interfaces are being developed for at least three graphics packages, and Python interpreter and applications have been built on distributed platforms such as meiko and Cray T3D.

  13. A comparison of experimental and numerical results on convective thermal mixing of three vertical, quasi-planar jets

    SciTech Connect (OSTI)

    Tokuhiro, A.T.; Kimura, N.; Nishimura, M.; Kobayashi, J.; Miyakoshi, H.

    1999-07-01

    The thermal-hydraulic mixing of three quasi-planar vertical water jets was experimentally and numerically investigated. The central jet was initially 5 C lower in temperature than the other two. The hydraulic diameter and average exit velocity-based Reynolds and Richardson numbers were, Re{sub D} = 2 x 10{sup 4}, Ri{sub D} = 0.002. Besides temperature measurements from a traversing array of 37 thermocouples, velocity measurements were made using laser and ultrasound Doppler velocimetries (LDV and UDV). In parallel the in-house code, CASCADE, featuring a {kappa}-{epsilon} turbulence model was used to simulate the experimental flow configuration. A comparison of the experimental and numerical results showed that code validation by LDV/UDV was possible and in particular that time-averaged field and frequency characteristics of transversely swaying jets, even under Reynolds averaging of the conservation equations, could be simulated. A representative comparison of the amplitude of oscillation is shown in Figure A-1 with an inset of the visualized flow and sample time-series of the temperature fluctuations at the position indicated. The difference in the predominant frequency, the numerically predicted {approximately}1.6 Hz versus the experimental {approximately}2.25 Hz, is attributed to the turbulence model that overestimate thus effective fluid viscosity. Development of an accurate numerical simulation is of relevance to the design of the liquid metal fast breeder reactor (LMFBR), where the lack of mixing of the cold sodium may initiate thermal striping; that is, poorly mixed hot and cold streams may thermally stress the components onto which they impinge. Turbulent mixing of jets is equally of general interest to environmental and material processing flows.

  14. RELAP-7 Development Updates

    SciTech Connect (OSTI)

    Zhang, Hongbin; Zhao, Haihua; Gleicher, Frederick Nathan; DeHart, Mark David; Zou, Ling; Andrs, David; Martineau, Richard Charles

    2015-09-01

    RELAP-7 is a nuclear systems safety analysis code being developed at the Idaho National Laboratory, and is the next generation tool in the RELAP reactor safety/systems analysis application series. RELAP-7 development began in 2011 to support the Risk Informed Safety Margins Characterization (RISMC) Pathway of the Light Water Reactor Sustainability (LWRS) program. The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical methods, and physical models in order to provide capabilities needed for the RISMC methodology and to support nuclear power safety analysis. The code is being developed based on Idaho National Laboratory’s modern scientific software development framework – MOOSE (the Multi-Physics Object-Oriented Simulation Environment). The initial development goal of the RELAP-7 approach focused primarily on the development of an implicit algorithm capable of strong (nonlinear) coupling of the dependent hydrodynamic variables contained in the 1-D/2-D flow models with the various 0-D system reactor components that compose various boiling water reactor (BWR) and pressurized water reactor nuclear power plants (NPPs). During Fiscal Year (FY) 2015, the RELAP-7 code has been further improved with expanded capability to support boiling water reactor (BWR) and pressurized water reactor NPPs analysis. The accumulator model has been developed. The code has also been coupled with other MOOSE-based applications such as neutronics code RattleSnake and fuel performance code BISON to perform multiphysics analysis. A major design requirement for the implicit algorithm in RELAP-7 is that it is capable of second-order discretization accuracy in both space and time, which eliminates the traditional first-order approximation errors. The second-order temporal is achieved by a second-order backward temporal difference, and the one-dimensional second-order accurate spatial discretization is achieved with the Galerkin approximation of Lagrange finite elements. During FY-2015, we have done numerical verification work to verify that the RELAP-7 code indeed achieves 2nd-order accuracy in both time and space for single phase models at the system level.

  15. TOUGH2: A general-purpose numerical simulator for multiphase nonisothermal flows

    SciTech Connect (OSTI)

    Pruess, K.

    1991-06-01

    Numerical simulators for multiphase fluid and heat flows in permeable media have been under development at Lawrence Berkeley Laboratory for more than 10 yr. Real geofluids contain noncondensible gases and dissolved solids in addition to water, and the desire to model such `compositional` systems led to the development of a flexible multicomponent, multiphase simulation architecture known as MULKOM. The design of MULKOM was based on the recognition that the mass-and energy-balance equations for multiphase fluid and heat flows in multicomponent systems have the same mathematical form, regardless of the number and nature of fluid components and phases present. Application of MULKOM to different fluid mixtures, such as water and air, or water, oil, and gas, is possible by means of appropriate `equation-of-state` (EOS) modules, which provide all thermophysical and transport parameters of the fluid mixture and the permeable medium as a function of a suitable set of primary thermodynamic variables. Investigations of thermal and hydrologic effects from emplacement of heat-generating nuclear wastes into partially water-saturated formations prompted the development and release of a specialized version of MULKOM for nonisothermal flow of water and air, named TOUGH. TOUGH is an acronym for `transport of unsaturated groundwater and heat` and is also an allusion to the tuff formations at Yucca Mountain, Nevada. The TOUGH2 code is intended to supersede TOUGH. It offers all the capabilities of TOUGH and includes a considerably more general subset of MULKOM modules with added capabilities. The paper briefly describes the simulation methodology and user features.

  16. sustainable development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    sustainable development - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Hydrogen Infrastructure Hydrogen Production Market Transformation Fuel Cells ...

  17. Feasibility studies for the development of petroleum areas. Integrated exploitation project of the fields in the area north of Santa Cruz. Volume 2. Tables and figures. Export trade information

    SciTech Connect (OSTI)

    Not Available

    1991-03-01

    The report, generated by Scientific Software-Intercomp, Inc. for Yacimientos Petroliferos Fiscales Bolivianos, documents the results of a feasibility study which addressed the viability of developing petroleum areas in Bolivia. The primary objective of the project was to describe the reservoirs that have been discovered and their reserves, describe which would be the best alternatives for development of these reservoirs, and to determine the best alternatives for development of all the reserves together. The report, volume 2 of 4 contains Tables and Figures.

  18. Options for developing countries in mining development

    SciTech Connect (OSTI)

    Walrond, G.W.; Kumar, R.

    1985-01-01

    This book is a study of the issues that developing countries face in planning and implementing mineral development, taking as case studies Botswana, Sierra Leone, Zambia, Tanzania, Malaysia, Papua New Guinea and the developed states of Quebec and Western Australia. The authors consider the major aspects of the matter including organization and administration; regulation; taxation and surplus distribution; the dynamics of such instruments as royalty, rent resource tax and capital allowances under various cost/price scenarios; and selected mining agreements and their key provisions. They stress throughout the need for foreign investment while maximizing the economic benefits reaped from exhaustible resources.

  19. Joint physical and numerical modeling of water distribution networks.

    SciTech Connect (OSTI)

    Zimmerman, Adam; O'Hern, Timothy John; Orear, Leslie Jr.; Kajder, Karen C.; Webb, Stephen Walter; Cappelle, Malynda A.; Khalsa, Siri Sahib; Wright, Jerome L.; Sun, Amy Cha-Tien; Chwirka, J. Benjamin; Hartenberger, Joel David; McKenna, Sean Andrew; van Bloemen Waanders, Bart Gustaaf; McGrath, Lucas K.; Ho, Clifford Kuofei

    2009-01-01

    This report summarizes the experimental and modeling effort undertaken to understand solute mixing in a water distribution network conducted during the last year of a 3-year project. The experimental effort involves measurement of extent of mixing within different configurations of pipe networks, measurement of dynamic mixing in a single mixing tank, and measurement of dynamic solute mixing in a combined network-tank configuration. High resolution analysis of turbulence mixing is carried out via high speed photography as well as 3D finite-volume based Large Eddy Simulation turbulence models. Macroscopic mixing rules based on flow momentum balance are also explored, and in some cases, implemented in EPANET. A new version EPANET code was developed to yield better mixing predictions. The impact of a storage tank on pipe mixing in a combined pipe-tank network during diurnal fill-and-drain cycles is assessed. Preliminary comparison between dynamic pilot data and EPANET-BAM is also reported.

  20. Low-cost phase change material as an energy storage medium in building envelopes: Experimental and numerical analyses

    SciTech Connect (OSTI)

    Biswas, Kaushik; Abhari, Mr. Ramin

    2014-01-01

    A promising approach to increasing the energy efficiency of buildings is the implementation of a phase change material (PCM) in the building envelope. Numerous studies over the last two decades have reported the energy saving potential of PCMs in building envelopes, but their wide application has been inhibited, in part, by their high cost. This article describes a novel PCM made of naturally occurring fatty acids/glycerides trapped into high density polyethylene (HDPE) pellets and its performance in a building envelope application. The PCM-HDPE pellets were mixed with cellulose insulation and then added to an exterior wall of a test building in a hot and humid climate, and tested over a period of several months, To demonstrate the efficacy of the PCM-enhanced cellulose insulation in reducing the building envelope heat gains and losses, side-by-side comparison was performed with another wall section filled with cellulose-only insulation. Further, numerical modeling of the test wall was performed to determine the actual impact of the PCM-HDPE pellets on wall-generated heating and cooling loads and the associated electricity consumption. The model was first validated using experimental data and then used for annual simulations using typical meteorological year (TMY3) weather data. This article presents the experimental data and numerical analyses showing the energy-saving potential of the new PCM.

  1. Low-cost phase change material as an energy storage medium in building envelopes: Experimental and numerical analyses

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Biswas, Kaushik; Abhari, Mr. Ramin

    2014-01-01

    A promising approach to increasing the energy efficiency of buildings is the implementation of a phase change material (PCM) in the building envelope. Numerous studies over the last two decades have reported the energy saving potential of PCMs in building envelopes, but their wide application has been inhibited, in part, by their high cost. This article describes a novel PCM made of naturally occurring fatty acids/glycerides trapped into high density polyethylene (HDPE) pellets and its performance in a building envelope application. The PCM-HDPE pellets were mixed with cellulose insulation and then added to an exterior wall of a test buildingmore » in a hot and humid climate, and tested over a period of several months, To demonstrate the efficacy of the PCM-enhanced cellulose insulation in reducing the building envelope heat gains and losses, side-by-side comparison was performed with another wall section filled with cellulose-only insulation. Further, numerical modeling of the test wall was performed to determine the actual impact of the PCM-HDPE pellets on wall-generated heating and cooling loads and the associated electricity consumption. The model was first validated using experimental data and then used for annual simulations using typical meteorological year (TMY3) weather data. This article presents the experimental data and numerical analyses showing the energy-saving potential of the new PCM.« less

  2. Numerical simulation of ground-water flow in the Culebra dolomite at the Waste Isolation Pilot Plant (WIPP) site: Second interim report

    SciTech Connect (OSTI)

    LaVenue, A.M.; Haug, A.; Kelley, V.A.

    1988-03-01

    This hydrogeologic modeling study has been performed as part of the regional hydrologic characterization of the Waste Isolation Pilot Plant (WIPP) Site in southeastern New Mexico. The study resulted in an estimation of the transmissivity distrubution, hydraulic potentials, flow field, and fluid densities in the Culebra Dolomite Member of the Permian Rustler Formation at the WIPP site. The three-dimensional finite-difference code SWIFT-II was employed for the numerical modeling, using variable-fluid-density and a single-porosity formulation. The modeled area includes and extends beyond the WIPP controlled zone (Zone 3). The work performed consisted of modeling the hydrogeology of the Culebra using two approaches: (1) steady-state modeling to develop the best estimate of the undisturbed head distribution, i.e., of the situation before sinking if the WIPP shafts, which began in 1981; and (2) superimposed transient modeling of local hydrologic responses to excavation of the three WIPP shafts at the center of the WIPP site, as well as to various well tests. Boundary conditions (prescribed constant fluid pressures and densities) were estimated using hydraulic-head and fluid-density data obtained from about 40 wells at and near the WIPP site. The transient modeling used the calculated steady-state freshwater heads as initial conditions. 107 refs., 112 figs., 22 tabs.

  3. Hanford Site Development Plan

    SciTech Connect (OSTI)

    Rinne, C.A.; Curry, R.H.; Hagan, J.W.; Seiler, S.W.; Sommer, D.J. ); Yancey, E.F. )

    1990-01-01

    The Hanford Site Development Plan (Site Development Plan) is intended to guide the short- and long-range development and use of the Hanford Site. All acquisition, development, and permanent facility use at the Hanford Site will conform to the approved plan. The Site Development Plan also serves as the base document for all subsequent studies that involve use of facilities at the Site. This revision is an update of a previous plan. The executive summary presents the highlights of the five major topics covered in the Site Development Plan: general site information, existing conditions, planning analysis, Master Plan, and Five-Year Plan. 56 refs., 67 figs., 31 tabs.

  4. Two-dimensional numerical simulation of a Stirling engine heat exchanger

    SciTech Connect (OSTI)

    Ibrahim, M.B.; Tew, R.C.; Dudenhoefer, J.E.

    1994-09-01

    This paper describes the first phase of an effort to develop multidimensional models of Stirling engine components; the ultimate goal is to model an entire engine working space. More specifically, this paper describes parallel plate and tubular heat exchanger models with emphasis on the central part of the channel (i.e., ignoring hydrodynamic and thermal end effects). The model assumes: Laminar, incompressible flow with constant thermophysical properties. In addition, a constant axial temperature gradient is imposed. The governing equations, describing the model, have been solved Crack-Nicloson finite-difference scheme. Model predictions have been compared with analytical solutions for oscillating/reversing flow and heat transfer in order to check numerical accuracy. The simplifying assumptions will later be relaxed to permit modeling of incompressible, laminar/turbulent flow that occurs in Stirling heat exchanger. Excellent agreement has been obtained for the model predictions with analytical solutions available for both flow in circular tubes and between parallel plates. Also the heat transfer computational results are in good agreement with the heat transfer analytical results for parallel plates.

  5. Terascale Direct Numerical Simulations of Turbulent Combustion: Capabilities and Limits (PReSS Talk)

    SciTech Connect (OSTI)

    Yoo, Chun Sang

    2009-03-26

    The rapid growth in computational capabilities has provided great opportunities for direct numerical simulations (DNS) of turbulent combustion, a type of simulations without any turbulence model. With the help of terascale high performance supercomputing (HPC) resources, we are now able to provide fundamental insight into turbulence-chemistry interaction in simple laboratory-scale turbulent flames with detailed chemistry using three-dimensional (3D) DNS. However, the actual domain size of 3D-DNS is still limited within {approx} O(10 cm{sup 3}) due to its tremendously high grid resolution required to resolve the smallest turbulent length scale as well as flame structures. Moreover, 3D-DNS will require more computing powers to investigate next-generation engines, of which operating conditions will be characterized by higher pressures, lower temperatures, and higher levels of dilution. In this talk, I will discuss the capabilities and limits of DNS of turbulent combustion and present some results of ignition/extinction characteristics of a highly diluted hydrogen flame counter-flowing against heated air. The results of our recent 3D-DNS of a spatially-developing turbulent lifted hydrogen jet flame in heated coflow will also be presented. The 3D-DNS was performed at a jet Reynolds number of 11,000 with {approx} 1 billion grid points, which required 3.5 million CPU hours on Cray XT3/XT4 at Oak Ridge National Laboratories.

  6. Numerical simulation of gas flow through unsaturated fractured rock at Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    Cooper, C.A.

    1990-01-01

    Numerical analysis is used to identify the physical phenomena associated with barometrically driven gas (air and water vapor) flow through unsaturated fractured rock at Yucca Mountain, Nevada. Results from simple finite difference simulations indicate that for a fractured rock scenario, the maximum velocity of air out of an uncased 10 cm borehole is 0.002 m s{sub {minus}1}. An equivalent porous medium (EPM) model was incorporated into a multiphase, multicomponent simulator to test more complex conceptual models. Results indicate that for a typical June day, a diurnal pressure wave propagates about 160 m into the surrounding Tiva Canyon hydrogeologic unit. Dry air that enters the formation evaporates water around the borehole which reduces capillary pressure. Multiphase countercurrent flow develops in the vicinity of the hole; the gas phase flows into the formation while the liquid phase flows toward the borehole. The effect occurs within 0.5 m of the borehole. The amount of water vapor leaving the formation during 1 day is 900 cm{sup 3}. This is less than 0.1% of the total recharge into the formation, suggesting that the barometric effect may be insignificant in drying the unsaturated zone. However, gas phase velocities out of the borehole (3 m s{sup {minus}1}), indicating that observed flow rates from wells along the east flank of Yucca Mountain were able to be simulated with a barometric model.

  7. An investigation of the information propagation and entropy transport aspects of Stirling-machine numerical simulation. Final Report

    SciTech Connect (OSTI)

    Goldberg, L.F.

    1992-04-01

    Aspects of the information propagation modeling behavior of integral machine computer simulation programs are investigated in terms of a transmission line. In particular, the effects of pressure-linking and temporal integration algorithms on the amplitude ratio and phase angle predictions are compared against experimental and closed-form analytic data. It is concluded that the discretized, first order conservation balances may not be adequate for modeling information propagation effects at characteristic numbers less than about 24. An entropy transport equation suitable for generalized use in Stirling machine simulation is developed. The equation is evaluated by including it in a simulation of an incompressible oscillating flow apparatus designed to demonstrate the effect of flow oscillations on the enhancement of thermal diffusion. Numerical false diffusion is found to be a major factor inhibiting validation of the simulation predictions with experimental and closed-form analytic data. A generalized false diffusion correction algorithm is developed which allows the numerical results to match their analytic counterparts. Under these conditions, the simulation yields entropy predictions which satisfy Clausius' inequality.

  8. Numerical simulation of laminar plasma dynamos in a cylindrical von Karman flow

    SciTech Connect (OSTI)

    Khalzov, I. V.; Brown, B. P.; Schnack, D. D.; Forest, C. B. [University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706 (United States); Ebrahimi, F. [University of New Hampshire, 8 College Road, Durham, New Hampshire 03824 (United States)

    2011-03-15

    The results of a numerical study of the magnetic dynamo effect in cylindrical von Karman plasma flow are presented with parameters relevant to the Madison Plasma Couette Experiment. This experiment is designed to investigate a broad class of phenomena in flowing plasmas. In a plasma, the magnetic Prandtl number Pm can be of order unity (i.e., the fluid Reynolds number Re is comparable to the magnetic Reynolds number Rm). This is in contrast to liquid metal experiments, where Pm is small (so, Re>>Rm) and the flows are always turbulent. We explore dynamo action through simulations using the extended magnetohydrodynamic NIMROD code for an isothermal and compressible plasma model. We also study two-fluid effects in simulations by including the Hall term in Ohm's law. We find that the counter-rotating von Karman flow results in sustained dynamo action and the self-generation of magnetic field when the magnetic Reynolds number exceeds a critical value. For the plasma parameters of the experiment, this field saturates at an amplitude corresponding to a new stable equilibrium (a laminar dynamo). We show that compressibility in the plasma results in an increase of the critical magnetic Reynolds number, while inclusion of the Hall term in Ohm's law changes the amplitude of the saturated dynamo field but not the critical value for the onset of dynamo action.

  9. Comparison Between Numerical and Experimental Results on Mechanical Stirrer and Bubbling in a Cylindrical Tank - 13047

    SciTech Connect (OSTI)

    Lima da Silva, M.; Sauvage, E.; Brun, P.; Gagnoud, A.; Fautrelle, Y.; Riva, R.

    2013-07-01

    The process of vitrification in a cold crucible heated by direct induction is used in the fusion of oxides. Its feature is the production of high-purity materials. The high-level of purity of the molten is achieved because this melting technique excludes the contamination of the charge by the crucible. The aim of the present paper is to analyze the hydrodynamic of the vitrification process by direct induction, with the focus in the effects associated with the interaction between the mechanical stirrer and bubbling. Considering the complexity of the analyzed system and the goal of the present work, we simplified the system by not taking into account the thermal and electromagnetic phenomena. Based in the concept of hydraulic similitude, we performed an experimental study and a numerical modeling of the simplified model. The results of these two studies were compared and showed a good agreement. The results presented in this paper in conjunction with the previous work contribute to a better understanding of the hydrodynamics effects resulting from the interaction between the mechanical stirrer and air bubbling in the cold crucible heated by direct induction. Further works will take into account thermal and electromagnetic phenomena in the presence of mechanical stirrer and air bubbling. (authors)

  10. Two-dimensional numerical simulation of boron diffusion for pyramidally textured silicon

    SciTech Connect (OSTI)

    Ma, Fa-Jun Duttagupta, Shubham; Shetty, Kishan Devappa; Meng, Lei; Hoex, Bram; Peters, Ian Marius; Samudra, Ganesh S.

    2014-11-14

    Multidimensional numerical simulation of boron diffusion is of great relevance for the improvement of industrial n-type crystalline silicon wafer solar cells. However, surface passivation of boron diffused area is typically studied in one dimension on planar lifetime samples. This approach neglects the effects of the solar cell pyramidal texture on the boron doping process and resulting doping profile. In this work, we present a theoretical study using a two-dimensional surface morphology for pyramidally textured samples. The boron diffusivity and segregation coefficient between oxide and silicon in simulation are determined by reproducing measured one-dimensional boron depth profiles prepared using different boron diffusion recipes on planar samples. The established parameters are subsequently used to simulate the boron diffusion process on textured samples. The simulated junction depth is found to agree quantitatively well with electron beam induced current measurements. Finally, chemical passivation on planar and textured samples is compared in device simulation. Particularly, a two-dimensional approach is adopted for textured samples to evaluate chemical passivation. The intrinsic emitter saturation current density, which is only related to Auger and radiative recombination, is also simulated for both planar and textured samples. The differences between planar and textured samples are discussed.

  11. Liquid phase methanol LaPorte process development unit: Modification operation, and support studies. Task 3.6/3.7: Alternative catalyst/life run

    SciTech Connect (OSTI)

    Not Available

    1991-01-28

    In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.

  12. Lessons from Iowa : development of a 270 megawatt compressed air energy storage project in midwest Independent System Operator : a study for the DOE Energy Storage Systems Program.

    SciTech Connect (OSTI)

    Holst, Kent; Huff, Georgianne; Schulte, Robert H.; Critelli, Nicholas

    2012-01-01

    The Iowa Stored Energy Park was an innovative, 270 Megawatt, $400 million compressed air energy storage (CAES) project proposed for in-service near Des Moines, Iowa, in 2015. After eight years in development the project was terminated because of site geological limitations. However, much was learned in the development process regarding what it takes to do a utility-scale, bulk energy storage facility and coordinate it with regional renewable wind energy resources in an Independent System Operator (ISO) marketplace. Lessons include the costs and long-term economics of a CAES facility compared to conventional natural gas-fired generation alternatives; market, legislative, and contract issues related to enabling energy storage in an ISO market; the importance of due diligence in project management; and community relations and marketing for siting of large energy projects. Although many of the lessons relate to CAES applications in particular, most of the lessons learned are independent of site location or geology, or even the particular energy storage technology involved.

  13. Program Development

    SciTech Connect (OSTI)

    Atencio, Julian J.

    2014-05-01

    This presentation covers how to go about developing a human reliability program. In particular, it touches on conceptual thinking, raising awareness in an organization, the actions that go into developing a plan. It emphasizes evaluating all positions, eliminating positions from the pool due to mitigating factors, and keeping the process transparent. It lists components of the process and objectives in process development. It also touches on the role of leadership and the necessity for audit.

  14. Development of Physics-Based Numerical Models for Uncertainty Quantification of Selective Laser Melting Processes - 2015 Annual Progress Report

    SciTech Connect (OSTI)

    Anderson, A.; Delplanque, Jean-Pierre

    2015-10-08

    The primary goal of the proposed research is to characterize the influence of process parameter variability inherent to Selective Laser Melting (SLM) on components manufactured with the SLM technique for space flight systems and their performance.

  15. On the Numerical Dispersion of Electromagnetic Particle-In-Cell Code : Finite Grid Instability

    SciTech Connect (OSTI)

    Meyers, Michael David; Huang, Chengkun; Zeng, Yong; Yi, Sunghwan; Albright, Brian James

    2014-07-15

    The Particle-In-Cell (PIC) method is widely used in relativistic particle beam and laser plasma modeling. However, the PIC method exhibits numerical instabilities that can render unphysical simulation results or even destroy the simulation. For electromagnetic relativistic beam and plasma modeling, the most relevant numerical instabilities are the finite grid instability and the numerical Cherenkov instability. We review the numerical dispersion relation of the electromagnetic PIC algorithm to analyze the origin of these instabilities. We rigorously derive the faithful 3D numerical dispersion of the PIC algorithm, and then specialize to the Yee FDTD scheme. In particular, we account for the manner in which the PIC algorithm updates and samples the fields and distribution function. Temporal and spatial phase factors from solving Maxwell's equations on the Yee grid with the leapfrog scheme are also explicitly accounted for. Numerical solutions to the electrostatic-like modes in the 1D dispersion relation for a cold drifting plasma are obtained for parameters of interest. In the succeeding analysis, we investigate how the finite grid instability arises from the interaction of the numerical 1D modes admitted in the system and their aliases. The most significant interaction is due critically to the correct representation of the operators in the dispersion relation. We obtain a simple analytic expression for the peak growth rate due to this interaction.

  16. Numerical simulation of a wave-guide mixing layer on a Cray C-90

    SciTech Connect (OSTI)

    Greenough, J.A.; Crutchfield, W.Y.; Rendleman, C.A.

    1995-05-19

    The development of a three-dimensional spatially evolving compressible mixing layer is investigated numerically using a parallel implementation of Adaptive Mesh Refinement (AMR) on a Cray C-90. The parallel implementation allowed the flow to be highly resolved while significantly reducing the wall-clock runtime. A sustained computation rate of 5.3 Gigaflops including I/O was obtained for a typical production run on a 16 processor machine. A novel mixing layer configuration is investigated where a pressure mismatch is maintained between the two inlet streams. In addition, the sonic character of the two streams is sufficiently different so that the pressure relief wave is trapped in the high speed stream. The trapped wave forces the mixing layer to form a characteristic cellular pattern. The cellular structure introduces curvature into the mixing layer that excites centrifugal instabilities characterized by large-scale counter-rotating vortical pairs embedded within the mixing layer. These are the dominant feature of the flow. Visualizations of these structures in cross-section show the pumping action which lifts dense fluid up into light gas. This effect has a strong impact on mixing enhancement as monitored by a conserved scalar formulation. Once the large-scale structures axe well established in the flow and undergo intensification from favorable velocity gradients, the time-averaged integrated product shows almost a four-fold increase. A spectral analysis of the flow-field over the cellular structures, as part of a full space-time analysis, shows these structures to be zero-frequency modes that develop from low level essentially broad-banded noise. This characterization of the vortical structures and their appearance is consistent with a recent linear stability analysis, of a mixing layer over a curved wall that predicts the most unstable modes to be zero frequency streamwise vortices.

  17. A NUMERICAL MODEL OF STANDARD TO BLOWOUT JETS

    SciTech Connect (OSTI)

    Archontis, V.; Hood, A. W.

    2013-06-01

    We report on three-dimensional (3D) MHD simulations of the formation of jets produced during the emergence and eruption of solar magnetic fields. The interaction between an emerging and an ambient magnetic field in the solar atmosphere leads to (external) reconnection and the formation of ''standard'' jets with an inverse Y-shaped configuration. Eventually, low-atmosphere (internal) reconnection of sheared fieldlines in the emerging flux region produces an erupting magnetic flux rope and a reconnection jet underneath it. The erupting plasma blows out the ambient field and, moreover, it unwinds as it is ejected into the outer solar atmosphere. The fast emission of the cool material that erupts together with the hot outflows due to external/internal reconnection form a wider ''blowout'' jet. We show the transition from ''standard'' to ''blowout'' jets and report on their 3D structure. The physical plasma properties of the jets are consistent with observational studies.

  18. Technique development for uiper critical field studies of SmFeAs(O,F) in the 300T single turn system

    SciTech Connect (OSTI)

    Mcdonald, Ross D [Los Alamos National Laboratory; Balakirev, F. F. [Los Alamos National Laboratory; Altarawneh, M. M. [Los Alamos National Laboratory; Betts, J [Los Alamos National Laboratory; Mielke, C. H. [Los Alamos National Laboratory; Moll, Philip Jw [ETH ZURICH; Zhigadlo, N D [ETH ZURICH; Karpinski, J [ETH ZURICH; Batlogg, B. [ETH ZURICH

    2011-01-14

    In high temperature superconductors, such as the most recent class of iron pnictides, extremely high upper critical fields H{sub c2} are common. The determination of H{sub c2}(T) is crucial to understand the detailed nature of the superconductor, in particular H{sub c2}(T = 0K) is of great interest. It is not only related to fundamental properties of the system, it is furthermore of great importance for materials science, as it is the ultimate limit of applicability of this superconductor in high field applications. However, this important quantity can only be estimated by extrapolation, as H{sub c2}(T = 0K) well exceeds hundreds of Tesla in optimally doped SillFeAs(O,F). We are developing methods to measure Ha(T) in direct transport in the extreme magnetic fields generated by the LANL single turn magnet.

  19. An economic prefeasibility study of geothermal energy development at Platanares, Honduras. Estudio economico de prefactibilidad del desarrollo de energia geotermica en Platanares, Honduras

    SciTech Connect (OSTI)

    Trocki, L.K.

    1989-09-01

    The expected economic benefits from development of a geothermal power plant at Platanares in the Department of Copan, Honduras are evaluated in this report. The economic benefits of geothermal plants ranging in size from a 10-MW plant in the shallow reservoir to a 20-, 30-, 55-, or 110-MW plant in the assumed deeper reservoir were measured by computing optimal expansion plans for each size of geothermal plant. Savings are computed as the difference in present value cost between a plan that contains no geothermal plant and one that does. Present value savings in millions of 1987 dollars range from $25 million for the 10-MW plant to $110 million for the 110-MW plant -- savings of 6% to 25% over the time period 1988 through 2008. 8 refs., 9 figs., 6 tabs.

  20. Numerical simulation of scattering of acoustic waves by inelastic bodies using hypersingular boundary integral equation

    SciTech Connect (OSTI)

    Daeva, S.G.; Setukha, A.V.

    2015-03-10

    A numerical method for solving a problem of diffraction of acoustic waves by system of solid and thin objects based on the reduction the problem to a boundary integral equation in which the integral is understood in the sense of finite Hadamard value is proposed. To solve this equation we applied piecewise constant approximations and collocation methods numerical scheme. The difference between the constructed scheme and earlier known is in obtaining approximate analytical expressions to appearing system of linear equations coefficients by separating the main part of the kernel integral operator. The proposed numerical scheme is tested on the solution of the model problem of diffraction of an acoustic wave by inelastic sphere.