National Library of Energy BETA

Sample records for numerical model validation

  1. Validation of Eddy-renewal model by numerical simulation

    E-Print Network [OSTI]

    Garbe, Christoph S.

    Validation of Eddy-renewal model by numerical simulation Li-Ping Hung1,2 , Christoph S. Garbe1, E-mail: wttsai@ncu.edu.tw Abstract. The eddy-renewal model proposes that the dominant vortical flows as the diffusivity effect in the thin diffusive sublayer beneath surface. Key Words: eddy-renewal model, numerical

  2. Validation of Erosion Modeling: Physical and Numerical Mehrad Kamalzare1

    E-Print Network [OSTI]

    Franklin, W. Randolph

    -3590 ABSTRACT The overall intent of this research is to develop numerical models of erosion of levees, dams is necessary for emergency plans for levee or dam breaches. Griffis, 2007 addressed the overall design and hydraulic shear stress. #12;2 Xu and Zhang (2009) found that in addition to soil type, the degree

  3. Numerical modeling and experimental validation of uniform microchamber filling in centrifugal microfluidics

    E-Print Network [OSTI]

    Banerjee, Debjyoti

    Numerical modeling and experimental validation of uniform microchamber filling in centrifugal analysis of microchamber filling in centrifugal microfluidics is presented. In the development of micro microchambers, such as those needed for nucleic acid amplification or detection. With centrifugal devices

  4. Development and validation of a vertically two-dimensional mesoscale numerical model 

    E-Print Network [OSTI]

    Walters, Michael Kent

    1985-01-01

    DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Submitted to the Graduate College of Texas AsM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE August 1985 Major Subject: Meteorology DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Approved as to style and content by: Dusan Djuric (Chair of Committee) WP...

  5. Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation

    SciTech Connect (OSTI)

    Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University

    2011-01-01

    A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

  6. Model Validation and Spatial Interpolation by Combining Observations with Outputs from Numerical

    E-Print Network [OSTI]

    Washington at Seattle, University of

    ""r,c,rn The authors are for hel]JfuI #12;Abstract Constructing maps of pollution levels is vital for air quality concentrations. Key tlJords: air pollution, Ba~yesian inference, change of support, likelihood approaches, Matern Resolutions 2.5 Modeling a Nonstationary Covariance . 3 Estimation 3.1 Algorithm 4 Application: Air Pollution

  7. A controlled distributed parameter model for a fluid-flexible structure system: numerical simulations and experiment validations

    E-Print Network [OSTI]

    Baudouin, Lucie

    A controlled distributed parameter model for a fluid-flexible structure system: numerical consider the problem of active reduction of vibrations in a fluid-flexible structure system and the sloshing of the fuel inside the wing's tank. The control is performed using piezoelectric patches

  8. Feature extraction for structural dynamics model validation

    SciTech Connect (OSTI)

    Hemez, Francois [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Nishio, Mayuko [UNIV OF TOKYO; Worden, Keith [UNIV OF SHEFFIELD; Takeda, Nobuo [UNIV OF TOKYO

    2010-11-08

    This study focuses on defining and comparing response features that can be used for structural dynamics model validation studies. Features extracted from dynamic responses obtained analytically or experimentally, such as basic signal statistics, frequency spectra, and estimated time-series models, can be used to compare characteristics of structural system dynamics. By comparing those response features extracted from experimental data and numerical outputs, validation and uncertainty quantification of numerical model containing uncertain parameters can be realized. In this study, the applicability of some response features to model validation is first discussed using measured data from a simple test-bed structure and the associated numerical simulations of these experiments. issues that must be considered were sensitivity, dimensionality, type of response, and presence or absence of measurement noise in the response. Furthermore, we illustrate a comparison method of multivariate feature vectors for statistical model validation. Results show that the outlier detection technique using the Mahalanobis distance metric can be used as an effective and quantifiable technique for selecting appropriate model parameters. However, in this process, one must not only consider the sensitivity of the features being used, but also correlation of the parameters being compared.

  9. Model Verification and Validation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete7 AssessmentBusinessAlternativeModel Verification and

  10. Lattice Boltzmann Model for Numerical Relativity

    E-Print Network [OSTI]

    Ilseven, E

    2015-01-01

    In the Bona-Masso formulation, Einstein equations are written as a set of flux conservative first order hyperbolic equations that resemble fluid dynamics equations. Based on this formulation, we construct a lattice Boltzmann model for Numerical Relativity. Our model is validated with well-established tests, showing good agreement with analytical solutions. Furthermore, we show that by increasing the relaxation time, we gain stability at the cost of losing accuracy, and by decreasing the lattice spacings while keeping a constant numerical diffusivity, the accuracy and stability of our simulations improves. Finally, in order to show the potential of our approach a linear scaling law for parallelisation with respect to number of CPU cores is demonstrated. Our model represents the first step in using lattice kinetic theory to solve gravitational problems.

  11. Laser spark plug numerical design process with experimental validation

    SciTech Connect (OSTI)

    McIntyre, D.; Woodruff, S.

    2011-01-01

    This work reports the numerical modeling design procedure for a miniaturized laser spark plug. In previous work both side pumped and end pumped laser spark plugs were empirically designed and tested. Experimental data from the previous laser spark plug development cycles is compared to the output predicted by a known set of rate equations. The rate equations are used to develop interrelated inter cavity time dependent waveforms that are then used to identify key variables. These variables are then input to a set of secondary equations for determining the output pulse energy, output power, and output pulse width of the simulated laser system. The physical meaning and the operation of the rate equations is explained in detail. This paper concentrates on the process and decision points needed to successfully design a solid state passively Q-switched laser system, either side pumped or end pumped, that produces the appropriate output needed for use as a laser spark plug for internal combustion engines.

  12. Lagrangian validation of numerical drifter trajectories using drifting buoys: Application to the Agulhas system

    E-Print Network [OSTI]

    van Leeuwen, Peter Jan

    Lagrangian validation of numerical drifter trajectories using drifting buoys: Application validation Kolmogorov­Smirnov statistics Drifting buoys a b s t r a c t The skill of numerical Lagrangian to the trajectories of drifting buoys in the real ocean. The skill assess- ment is performed using the two

  13. Passive millimeter-wave retrieval of global precipitation utilizing satellites and a numerical weather prediction model

    E-Print Network [OSTI]

    Surussavadee, Chinnawat

    2007-01-01

    This thesis develops and validates the MM5/TBSCAT/F([lambda]) model, composed of a mesoscale numerical weather prediction (NWP) model (MM5), a two-stream radiative transfer model (TBSCAT), and electromagnetic models for ...

  14. TEG On-Vehicle Performance & Model Validation

    Broader source: Energy.gov [DOE]

    Details efforts and results of steady-state and transient models validated with bench, engine dynamometer, and on-vehicle tests to measure actual performance

  15. Numerical wind speed simulation model

    SciTech Connect (OSTI)

    Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y.

    1981-09-01

    A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared.

  16. Design, Modeling, and Validation of a Flame Reformer for LNT...

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

    Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration...

  17. Probabilistic Methods for Model Validation 

    E-Print Network [OSTI]

    Halder, Abhishek

    2014-05-01

    Instead of Moments or Sets . . . . . 6 1.3.4 Methodology and Organization . . . . . . . . . . . . . . . . . 8 1.4 Contributions of This Dissertation . . . . . . . . . . . . . . . . . . . . 9 2. UNCERTAINTY PROPAGATION FOR DETERMINISTIC FLOW . . . . 12 2...’s Density Function Based Model Fal- sification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 4.6 Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 xv 5. CASE STUDY: F-16 CONTROLLER ROBUSTNESS VERIFICATION...

  18. Theoretical Study and Numerical Validation of Sound Radiation from Coaxial Annular Duct

    E-Print Network [OSTI]

    Huang, Xun

    Theoretical Study and Numerical Validation of Sound Radiation from Coaxial Annular Duct Xin Liu-infinite annular duct. Our problem is different from previous works in that both its inner pipe and outer pipe are semi-infinite. Hence, this problem is a better representative of aircraft engine bypass duct

  19. Numerical Model Construction with Closed Observables

    E-Print Network [OSTI]

    Felix Dietrich; Gerta Köster; Hans-Joachim Bungartz

    2015-10-18

    Performing analysis, optimization and control using simulations of many-particle systems is computationally demanding when no macroscopic model for the dynamics of the variables of interest is available. In case observations on the macroscopic scale can only be produced via legacy simulator code or live experiments, finding a model for these macroscopic variables is challenging. In this paper, we employ time-lagged embedding theory to construct macroscopic numerical models from output data of a black box, such as a simulator or live experiments. Since the state space variables of the constructed, coarse model are dynamically closed and observable by an observation function, we call these variables closed observables. The approach is an online-offline procedure, as model construction from observation data is performed offline and the new model can then be used in an online phase, independent of the original. We illustrate the theoretical findings with numerical models constructed from time series of a two-dimensional ordinary differential equation system, and from the density evolution of a transport-diffusion system. Applicability is demonstrated in a real-world example, where passengers leave a train and the macroscopic model for the density flow onto the platform is constructed with our approach. If only the macroscopic variables are of interest, simulation runtimes with the numerical model are three orders of magnitude lower compared to simulations with the original fine scale model. We conclude with a brief discussion of possibilities of numerical model construction in systematic upscaling, network optimization and uncertainty quantification.

  20. Maui Electrical System Simulation Model Validation

    E-Print Network [OSTI]

    Maui Electrical System Simulation Model Validation Prepared for the U.S. Department of Energy Office of Electricity Delivery and Energy Reliability Under Award No. DE-FC-06NT42847 Task 9 Deliverable was prepared by General Electric Company (GE) as an account of work sponsored by the Hawaii Natural Energy

  1. High performance computing and numerical modelling

    E-Print Network [OSTI]

    ,

    2014-01-01

    Numerical methods play an ever more important role in astrophysics. This is especially true in theoretical works, but of course, even in purely observational projects, data analysis without massive use of computational methods has become unthinkable. The key utility of computer simulations comes from their ability to solve complex systems of equations that are either intractable with analytic techniques or only amenable to highly approximative treatments. Simulations are best viewed as a powerful complement to analytic reasoning, and as the method of choice to model systems that feature enormous physical complexity such as star formation in evolving galaxies, the topic of this 43rd Saas Fee Advanced Course. The organizers asked me to lecture about high performance computing and numerical modelling in this winter school, and to specifically cover the basics of numerically treating gravity and hydrodynamics in the context of galaxy evolution. This is still a vast field, and I necessarily had to select a subset ...

  2. 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).

  3. Low frequency eddy current benchmark study for model validation

    SciTech Connect (OSTI)

    Mooers, R. D.; Boehnlein, T. R. [University of Dayton Research Institute, Structural Integrity Division, Dayton, OH, 45469 (United States); Cherry, M. R.; Knopp, J. S. [Air Force Research Lab, NDE Division, Wright Patterson, OH 45433 (United States); Aldrin, J. C. [Computational Tools, Gurnee, IL 60031 (United States); Sabbagh, H. A. [Victor Technologies LLC, Bloomington, IN 47401 (United States)

    2011-06-23

    This paper presents results of an eddy current model validation study. Precise measurements were made using an impedance analyzer to investigate changes in impedance due to Electrical Discharge Machining (EDM) notches in aluminum plates. Each plate contained one EDM notch at an angle of 0, 10, 20, or 30 degrees from the normal of the plate surface. Measurements were made with the eddy current probe both scanning parallel and perpendicular to the notch length. The experimental response from the vertical and oblique notches will be reported and compared to results from different numerical simulation codes.

  4. Boron-10 Lined Proportional Counter Model Validation

    SciTech Connect (OSTI)

    Lintereur, Azaree T.; Siciliano, Edward R.; Kouzes, Richard T.

    2012-06-30

    The Department of Energy Office of Nuclear Safeguards (NA-241) is supporting the project “Coincidence Counting With Boron-Based Alternative Neutron Detection Technology” at Pacific Northwest National Laboratory (PNNL) for the development of an alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a boron-lined proportional tube-based alternative system in the configuration of a coincidence counter. This report discusses the validation studies performed to establish the degree of accuracy of the computer modeling methods current used to simulate the response of boron-lined tubes. This is the precursor to developing models for the uranium neutron coincidence collar under Task 2 of this project.

  5. Demonstrating and Validating a Next Generation Model-Based Controller...

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

    a Next Generation Model-Based Controller for Fuel Efficient, Low Emissions Diesel Engines Demonstrating and Validating a Next Generation Model-Based Controller for Fuel...

  6. Sandia Energy - Tidal & Current Modeling Development and Validation

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

    Tidal & Current Modeling Development and Validation Home Stationary Power Energy Conversion Efficiency Water Power Technology Development Tidal & Current Modeling Development and...

  7. Validation Analysis of the Shoal Groundwater Flow and Transport Model

    SciTech Connect (OSTI)

    A. Hassan; J. Chapman

    2008-11-01

    Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical models of groundwater flow and radionuclide transport. Agreement on a contaminant boundary for the site and a corrective action plan was reached in 2006. Later that same year, three wells were installed for the purposes of model validation and site monitoring. The FFACO prescribes a five-year proof-of-concept period for demonstrating that the site groundwater model is capable of producing meaningful results with an acceptable level of uncertainty. The corrective action plan specifies a rigorous seven step validation process. The accepted groundwater model is evaluated using that process in light of the newly acquired data. The conceptual model of ground water flow for the Project Shoal Area considers groundwater flow through the fractured granite aquifer comprising the Sand Springs Range. Water enters the system by the infiltration of precipitation directly on the surface of the mountain range. Groundwater leaves the granite aquifer by flowing into alluvial deposits in the adjacent basins of Fourmile Flat and Fairview Valley. A groundwater divide is interpreted as coinciding with the western portion of the Sand Springs Range, west of the underground nuclear test, preventing flow from the test into Fourmile Flat. A very low conductivity shear zone east of the nuclear test roughly parallels the divide. The presence of these lateral boundaries, coupled with a regional discharge area to the northeast, is interpreted in the model as causing groundwater from the site to flow in a northeastward direction into Fairview Valley. Steady-state flow conditions are assumed given the absence of groundwater withdrawal activities in the area. The conceptual and numerical models were developed based upon regional hydrogeologic investigations conducted in the 1960s, site characterization investigations (including ten wells and various geophysical and geologic studies) at Shoal itself prior to and immediately after the test, and two site characterization campaigns in the 1990s for environmental restoration purposes (including eight wells and a year-long tracer test). The new wells are denoted MV-1, MV-2, and MV-3, and are located to the northnortheast of the nuclear test. The groundwater model was generally lacking data in the north-northeastern area; only HC-1 and the abandoned PM-2 wells existed in this area. The wells provide data on fracture orientation and frequency, water levels, hydraulic conductivity, and water chemistry for comparison with the groundwater model. A total of 12 real-number validation targets were available for the validation analysis, including five values of hydraulic head, three hydraulic conductivity measurements, three hydraulic gradient values, and one angle value for the lateral gradient in radians. In addition, the fracture dip and orientation data provide comparisons to the distributions used in the model and radiochemistry is available for comparison to model output. Goodness-of-fit analysis indicates that some of the model realizations correspond well with the newly acquired conductivity, head, and gradient data, while others do not. Other tests indicated that additional model realizations may be needed to test if the model input distributions need refinement to improve model performance. This approach (generating additional realizations) was not followed because it was realized that there was a temporal component to the data disconnect: the new head measurements are on the high side of the model distributions, but the heads at the original calibration locations themselves have also increased over time. This indicates that the steady-state assumption of the groundwater model is in error. To test the robustness of the model d

  8. 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.

  9. Full-Scale Cookoff Model Validation Experiments

    SciTech Connect (OSTI)

    McClelland, M A; Rattanapote, M K; Heimdahl, E R; Erikson, W E; Curran, P O; Atwood, A I

    2003-11-25

    This paper presents the experimental results of the third and final phase of a cookoff model validation effort. In this phase of the work, two generic Heavy Wall Penetrators (HWP) were tested in two heating orientations. Temperature and strain gage data were collected over the entire test period. Predictions for time and temperature of reaction were made prior to release of the live data. Predictions were comparable to the measured values and were highly dependent on the established boundary conditions. Both HWP tests failed at a weld located near the aft closure of the device. More than 90 percent of unreacted explosive was recovered in the end heated experiment and less than 30 percent recovered in the side heated test.

  10. Numerical Modeling of Eastern Connecticut's Visual Resources1

    E-Print Network [OSTI]

    Numerical Modeling of Eastern Connecticut's Visual Resources1 Daniel L. Civco 2/ l Submitted Conservation, The University of Connecticut, Storrs, Connecticut. / Abstract: A numerical model capable of accurately predicting the preference for landscape photographs of selected points in eastern Connecticut

  11. 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.

  12. Industrial validation models 1 4/23/03 Experimental validation of new software technology

    E-Print Network [OSTI]

    Zelkowitz, Marvin V.

    Industrial validation models 1 4/23/03 Experimental validation of new software technology Marvin V When to apply a new technology in an organization is a critical decision for every software development organization. Earlier work defines a set of methods that the research community uses when a new technology

  13. Experimental Testing and Model Validation for Ocean Wave Energy Harvesting Buoys

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Experimental Testing and Model Validation for Ocean Wave Energy Harvesting Buoys Douglas A. Gemme1 are presented for numerical simulations and field experiments using point absorption ocean wave energy and experimental data. Index Terms ­ energy conversion, wave energy harvesting, linear generator, ocean energy

  14. Validating

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidating extended MHD models for fusion

  15. INCORPORATION OF GROUNDWATER FLOW INTO NUMERICAL MODELS AND DESIGN MODELS

    E-Print Network [OSTI]

    -coupled, ground-source heat pumps, groundwater, heat pump, heat exchanger, heat transfer, numerical models-loop ground-coupled heat exchangers. Green and Perry (1961) demonstrated that the value of effective thermal on the design and performance of vertical closed-loop ground heat exchangers. Based on the investigation results

  16. Contributions Motivation Literature Models Synergy Measure Numerical Examples Conclusions Supply Chain Network Models for Humanitarian

    E-Print Network [OSTI]

    Nagurney, Anna

    Contributions Motivation Literature Models Synergy Measure Numerical Examples Conclusions Supply Motivation Literature Models Synergy Measure Numerical Examples Conclusions 1 Contributions 2 Motivation 3 University of Massachusetts Amherst #12;Contributions Motivation Literature Models Synergy Measure Numerical

  17. Bayesian-based simulation model validation for spacecraft thermal systems

    E-Print Network [OSTI]

    Stout, Kevin Dale

    2015-01-01

    Over the last several decades of space flight, spacecraft thermal system modeling software has advanced significantly, but the model validation process, in general, has changed very little. Although most thermal systems ...

  18. Fractional Euler-Bernoulli beams: theory, numerical study and experimental validation

    E-Print Network [OSTI]

    Wojciech Sumelka; Tomasz Blaszczyk; Christian Liebold

    2015-02-05

    In this paper the classical Euler-Bernoulli beam (CEBB) theory is reformulated utilising fractional calculus. Such generalisation is called fractional Euler-Bernoulli beams (FEBB) and results in non-local spatial description. The parameters of the model are identified based on AFM experiments concerning bending rigidities of micro-beams made of the polymer SU-8. In experiments both force as well as deflection data were recorded revealing significant size effect with respect to outer dimensions of the specimens. Special attention is also focused on the proper numerical solution of obtained fractional differential equation.

  19. System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report

    SciTech Connect (OSTI)

    Freeman, J.; Whitmore, J.; Kaffine, L.; Blair, N.; Dobos, A. P.

    2013-12-01

    The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.

  20. Systematic approach to verification and validation: High explosive burn models

    SciTech Connect (OSTI)

    Menikoff, Ralph [Los Alamos National Laboratory; Scovel, Christina A. [Los Alamos National Laboratory

    2012-04-16

    Most material models used in numerical simulations are based on heuristics and empirically calibrated to experimental data. For a specific model, key questions are determining its domain of applicability and assessing its relative merits compared to other models. Answering these questions should be a part of model verification and validation (V and V). Here, we focus on V and V of high explosive models. Typically, model developers implemented their model in their own hydro code and use different sets of experiments to calibrate model parameters. Rarely can one find in the literature simulation results for different models of the same experiment. Consequently, it is difficult to assess objectively the relative merits of different models. This situation results in part from the fact that experimental data is scattered through the literature (articles in journals and conference proceedings) and that the printed literature does not allow the reader to obtain data from a figure in electronic form needed to make detailed comparisons among experiments and simulations. In addition, it is very time consuming to set up and run simulations to compare different models over sufficiently many experiments to cover the range of phenomena of interest. The first difficulty could be overcome if the research community were to support an online web based database. The second difficulty can be greatly reduced by automating procedures to set up and run simulations of similar types of experiments. Moreover, automated testing would be greatly facilitated if the data files obtained from a database were in a standard format that contained key experimental parameters as meta-data in a header to the data file. To illustrate our approach to V and V, we have developed a high explosive database (HED) at LANL. It now contains a large number of shock initiation experiments. Utilizing the header information in a data file from HED, we have written scripts to generate an input file for a hydro code, run a simulation, and generate a comparison plot showing simulated and experimental velocity gauge data. These scripts are then applied to several series of experiments and to several HE burn models. The same systematic approach is applicable to other types of material models; for example, equations of state models and material strength models.

  1. NUMERICAL APPROXIMATION OF A MACROSCOPIC MODEL OF PEDESTRIAN FLOWS

    E-Print Network [OSTI]

    Chalons, Christophe

    NUMERICAL APPROXIMATION OF A MACROSCOPIC MODEL OF PEDESTRIAN FLOWS CHRISTOPHE CHALONS Abstract for the description of the flow of pedestrians. Solutions of the associated Riemann problem are known to be possibly in obtaining an efficient numerical scheme. Numerical evidences are proposed. Key words. macroscopic pedestrian

  2. A Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal...

    Open Energy Info (EERE)

    A Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal Reservoir Evaluation Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A...

  3. Numerical Modeling of the Nucleation Conditions of Petal-Centerline...

    Open Energy Info (EERE)

    Numerical Modeling of the Nucleation Conditions of Petal-Centerline Fractures below a Borehole Floor, A Sensitivity Study and Application to the Coso Geothermal Field Jump to:...

  4. Numerical Modeling of PCCI Combustion | Department of Energy

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

    PCCI Combustion Numerical Modeling of PCCI Combustion 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Lawrence Livermore National LaboratoryUniversity of...

  5. Validation of model based active control of combustion instability

    SciTech Connect (OSTI)

    Fleifil, M.; Ghoneim, Z.; Ghoniem, A.F.

    1998-07-01

    The demand for efficient, company and clean combustion systems have spurred research into the fundamental mechanisms governing their performance and means of interactively changing their performance characteristics. Thermoacoustic instability which is frequently observed in combustion systems with high power density, when burning close to the lean flammability limit, or using exhaust gas recirculation to meet more stringent emissions regulations, etc. Its occurrence and/or means to mitigate them passively lead to performance degradation such as reduced combustion efficiency, high local heat transfer rates, increase in the mixture equivalence ratio or system failure due to structural damage. This paper reports on their study of the origin of thermoacoustic instability, its dependence on system parameters and the means of actively controlling it. The authors have developed an analytical model of thermoacoustic instability in premixed combustors. The model combines a heat release dynamics model constructed using the kinematics of a premixed flame stabilized behind a perforated plate with the linearized conservation equations governing the system acoustics. This formulation allows model based controller design. In order to test the performance of the analytical model, a numerical solution of the partial differential equations governing the system has been carried out using the principle of harmonic separation and focusing on the dominant unstable mode. This leads to a system of ODEs governing the thermofluid variables. Analytical predictions of the frequency and growth ate of the unstable mode are shown to be in good agreement with the numerical simulations as well s with those obtained using experimental identification techniques when applied to a laboratory combustor. The authors use these results to confirm the validity of the assumptions used in formulating the analytical model. A controller based on the minimization of a cost function using the LQR technique has been designed using the analytical model and implemented on a bench top laboratory combustor. The authors show that the controller is capable of suppressing the pressure oscillations in the combustor with a settling time much shorter than what had been attained before and without exciting secondary peaks.

  6. Multi-terminal Subsystem Model Validation for Pacific DC Intertie

    SciTech Connect (OSTI)

    Yang, Bo; Huang, Zhenyu; Kosterev, Dmitry

    2008-07-20

    this paper proposes to validate dynamic model of Pacific DC Intertie with the concept of hybrid simulation by combing simulation with PMU measurements. The Playback function available in GE PSLF is adopted for hybrid simulation. It is demonstrated for the first time the feasibility of using Playback function on multi-terminal subsystem. Sensitivity studies are also presented as a result of common PMU measurement quality problem, ie, offset noise and time synchronization. Results indicate a good tolerance of PDCI model generally. It is recommended that requirements should apply to phasor measurements in model validation work to ensure better analysis. Key parameters are identified based on impact of value change to model behavior. Two events are employed for preliminary model validation with PMU measurements. Suggestions are made for PDCI model validation work in the future.

  7. Starting laminar plumes: Comparison of laboratory and numerical modeling

    E-Print Network [OSTI]

    van Keken, Peter

    Starting laminar plumes: Comparison of laboratory and numerical modeling Judith Vatteville Institut, France (davaille@fast.u-psud.fr) [1] A detailed comparison of starting laminar plumes in viscous fluids. Davaille (2009), Starting laminar plumes: Comparison of laboratory and numerical modeling, Geochem. Geophys

  8. Evolution of the Bohemian Massif: Insights from numerical modeling

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Evolution of the Bohemian Massif: Insights from numerical modeling Petra Maierová Supervisor: Doc of Geophysics Faculty of Mathematics and Physics Charles University in Prague #12;February 4, 2013Evolution Conclusions Outline #12;February 4, 2013Evolution of the Bohemian Massif: Insights from numerical modeling 3

  9. NUMERICAL MODELING OF LOW FREQUENCY HYDRO-ACOUSTIC WAVES

    E-Print Network [OSTI]

    Kirby, James T.

    NUMERICAL MODELING OF LOW FREQUENCY HYDRO-ACOUSTIC WAVES GENERATED BY SUBMARINE TSUNAMIGENIC#al to increase the reliability of the system · Can we use precursors of tsunami? Hydro numerical models applicable on an oceanic scale #12;Index · Introduc#on on hydro

  10. Numerical models of phosphate esters in the Chattahoochee River

    E-Print Network [OSTI]

    Haffey, Samuel Fraad, 1973-

    2004-01-01

    A numerical model was constructed to assess the magnitude of organophosphoric acid triester sinks in the Chattahoochee River and to identify concentration patterns downstream of point source discharges. The model was built ...

  11. A numerical model simulation of longshore transport for Galveston Island 

    E-Print Network [OSTI]

    Gilbreath, Stephen Alexander

    1995-01-01

    The shoreline changes, deposition patterns, and longshore transport rates were calculated for the coast of Galveston Island using a numerical model simulation. The model only simulated changes due to waves creating longshore currents. East Beach...

  12. Particulate dispersion apparatus for the validation of plume models 

    E-Print Network [OSTI]

    Bala, William D

    2001-01-01

    The purpose of this thesis is to document design, development, and fabrication of a transportable source of dry aerosol to improve testing and validation of atmospheric plume models. The proposed dispersion apparatus is intended to complement...

  13. O`ahu Grid Study: Validation of Grid Models

    E-Print Network [OSTI]

    O`ahu Grid Study: Validation of Grid Models Prepared for the U.S. Department of Energy Office Resource Technologies for Energy Security Subtask 7.2 Deliverable By GE Global Research Niskayuna, New York

  14. Numerical study of energy diffusion in King models

    E-Print Network [OSTI]

    Tom Theuns

    1995-11-07

    The energy diffusion coefficients D_n(E) (n=1,2) for a system of equal mass particles moving self-consistently in an N-body realisation of a King model are computed from the probability per unit time, P(E, Delta E), that a star with initial energy E will undergo an energy change Delta E. In turn, P is computed from the number of times during the simulation that a particle in a state of given energy undergoes a transition to another state. These particle states are defined directly from the time evolution of E by identifying them with the event occuring between two local maxima in the E(t) curve. If one assumes next that energy changes are uncorrelated between different states, one can use diffusion theory to compute D_n(E). The simulations employ N=512, 2048,... , 32768 particles and are performed using an implementation of Aarseth's direct integrator N-body1 on a massively parallel computer. The more than seven million transitions measured in the largest N simulation provide excellent statistics. The numerically determined D(E)'s are compared against their theoretical counterparts which are computed from phase-space averaged rates of energy change due to independent binary encounters. The overall agreement between them is impressive over most of the energy range, notwithstanding the very different type of approximations involved, giving considerable support to the valid usage of these theoretical expressions to simulate dynamical evolution in Fokker-Planck type calculations.

  15. Nuclear Systems Modeling, Simulation & Validation | Nuclear Science...

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

    Research Areas Fuel Cycle Science & Technology Fusion Nuclear Science Isotope Development and Production Nuclear Security Science & Technology Nuclear Systems Modeling, Simulation...

  16. Category:Numerical Modeling | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank,CammackFLIR Jump to: navigation,GroundNear Infrared SurveysNumerical

  17. DEVELOPMENT AND VALIDATION OF A MULTIFIELD MODEL OF CHURN-TURBULENT GAS/LIQUID FLOWS

    SciTech Connect (OSTI)

    Elena A. Tselishcheva; Steven P. Antal; Michael Z. Podowski; Donna Post Guillen

    2009-07-01

    The accuracy of numerical predictions for gas/liquid two-phase flows using Computational Multiphase Fluid Dynamics (CMFD) methods strongly depends on the formulation of models governing the interaction between the continuous liquid field and bubbles of different sizes. The purpose of this paper is to develop, test and validate a multifield model of adiabatic gas/liquid flows at intermediate gas concentrations (e.g., churn-turbulent flow regime), in which multiple-size bubbles are divided into a specified number of groups, each representing a prescribed range of sizes. The proposed modeling concept uses transport equations for the continuous liquid field and for each bubble field. The overall model has been implemented in the NPHASE-CMFD computer code. The results of NPHASE-CMFD simulations have been validated against the experimental data from the TOPFLOW test facility. Also, a parametric analysis on the effect of various modeling assumptions has been performed.

  18. Data Assimilation for Idealised Mathematical Models of Numerical Weather Prediction

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Data Assimilation for Idealised Mathematical Models of Numerical Weather Prediction Supervisors). Background: Numerical Weather Prediction (NWP) has seen significant gains in accuracy in recent years due in weather dynamics, e.g., the asymptotic balance seen in high and low pressure systems. Aims of the project

  19. 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 validate statistical models Citation Details In-Document Search Title: Numerical simulations for...

  20. Validation of nuclear models used in space radiation shielding applications

    SciTech Connect (OSTI)

    Norman, Ryan B.; Blattnig, Steve R.

    2013-01-15

    A program of verification and validation has been undertaken to assess the applicability of models to space radiation shielding applications and to track progress as these models are developed over time. In this work, simple validation metrics applicable to testing both model accuracy and consistency with experimental data are developed. The developed metrics treat experimental measurement uncertainty as an interval and are therefore applicable to cases in which epistemic uncertainty dominates the experimental data. To demonstrate the applicability of the metrics, nuclear physics models used by NASA for space radiation shielding applications are compared to an experimental database consisting of over 3600 experimental cross sections. A cumulative uncertainty metric is applied to the question of overall model accuracy, while a metric based on the median uncertainty is used to analyze the models from the perspective of model development by examining subsets of the model parameter space.

  1. Fully kinetic numerical modeling of a plasma thruster

    E-Print Network [OSTI]

    Szabo, James Joseph, 1969-

    2001-01-01

    A Hall effect plasma thruster with conductive acceleration channel walls was numerically modeled using 2D3V Particle-in-Cell (PIC) and Monte-Carlo Collision (MCC) methodolo- gies. Electron, ion, and neutral dynamics were ...

  2. Vehicle Model Validation | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematics And Statistics » USAJobs Search USAJobs SearchWater-SavingofCode& Systems SimulationModel

  3. 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

  4. Experiments for foam model development and validation.

    SciTech Connect (OSTI)

    Bourdon, Christopher Jay; Cote, Raymond O.; Moffat, Harry K.; Grillet, Anne Mary; Mahoney, James F.; Russick, Edward Mark; Adolf, Douglas Brian; Rao, Rekha Ranjana; Thompson, Kyle Richard; Kraynik, Andrew Michael; Castaneda, Jaime N.; Brotherton, Christopher M.; Mondy, Lisa Ann; Gorby, Allen D.

    2008-09-01

    A series of experiments has been performed to allow observation of the foaming process and the collection of temperature, rise rate, and microstructural data. Microfocus video is used in conjunction with particle image velocimetry (PIV) to elucidate the boundary condition at the wall. Rheology, reaction kinetics and density measurements complement the flow visualization. X-ray computed tomography (CT) is used to examine the cured foams to determine density gradients. These data provide input to a continuum level finite element model of the blowing process.

  5. Stress and diffusion induced interface motion: Modelling and numerical simulations

    E-Print Network [OSTI]

    Styles, Vanessa

    Stress and diffusion induced interface motion: Modelling and numerical simulations Harald Garcke of Mathematics, University of Sussex, Brighton, BN1 9QH, U.K. Abstract We propose a phase field model for stress stress effects. In this paper we will demonstrate that the model can also be used to describe other

  6. 2D numerical simulation of the MEP energy-transport model with a finite difference scheme

    SciTech Connect (OSTI)

    Romano, V. . E-mail: romano@dmi.unict.it

    2007-02-10

    A finite difference scheme of Scharfetter-Gummel type is used to simulate a consistent energy-transport model for electron transport in semiconductors devices, free of any fitting parameters, formulated on the basis of the maximum entropy principle. Simulations of silicon n{sup +}-n-n{sup +} diodes, 2D-MESFET and 2D-MOSFET and comparisons with the results obtained by a direct simulation of the Boltzmann transport equation and with other energy-transport models, known in the literature, show the validity of the model and the robustness of the numerical scheme.

  7. Validity of numerical trajectories in the synchronization transition of complex systems

    E-Print Network [OSTI]

    R. L. Viana; C. Grebogi; S. E. de S. Pinto; S. R. Lopes; A. M. Batista; J. Kurths

    2003-10-07

    We investigate the relationship between the loss of synchronization and the onset of shadowing breakdown {\\it via} unstable dimension variability in complex systems. In the neighborhood of the critical transition to strongly non-hyperbolic behavior, the system undergoes on-off intermittency with respect to the synchronization state. There are potentially severe consequences of these facts on the validity of the computer-generated trajectories obtained from dynamical systems whose synchronization manifolds share the same non-hyperbolic properties.

  8. Utilization of a Validated Power System Model on Two

    E-Print Network [OSTI]

    Utilization of a Validated Power System Model on Two Scenarios: Base Case and High Wind Penetration. DE-FC-06NT42847 Task 1. Deliverable #4 ­ Conceptual Design Report By GE Global Research Niskayuna-956-8346 e-mail: rochelea@hawaii.edu Technical Contact at GE Global Research: Devon Manz Electric Power

  9. Direct Methanol Fuel Cell Experimental and Model Validation Study

    E-Print Network [OSTI]

    Wang, Chao-Yang

    Direct Methanol Fuel Cell Experimental and Model Validation Study M. Mench, J. Scott, S. Thynell boundary Fuel cell performance Current density distribution measurements Conclusions #12;3 Method, flow rate, species inlet and fuel cell temperature, and humidity. Transparent polycarbonate windows

  10. Utilization of a Validated Power System Model on Two

    E-Print Network [OSTI]

    Utilization of a Validated Power System Model on Two Scenarios: Base Case and High Wind Penetration, New York And University of Hawaii Hawaii Natural Energy Institute School of Ocean and Earth Science are presented. The business-as-usual and higher wind penetration scenarios have been built in both

  11. Design of Embedded Systems: Formal Models, Validation, and Synthesis

    E-Print Network [OSTI]

    Grosu, Radu

    critical situations, where reliability and safety are more important criteria than performance. TodayDesign of Embedded Systems: Formal Models, Validation, and Synthesis S. Edwards, L. Lavagno, E. A. Lee, and A. Sangiovanni-Vincentelli November 5, 1999 Abstract This paper addresses the design

  12. Validation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidating extended MHD

  13. Numerical modelling of tsunami mitigation by mangroves Putu Harry Gunawan

    E-Print Network [OSTI]

    Mancini, Simona

    Numerical modelling of tsunami mitigation by mangroves Putu Harry Gunawan LAMA (Laboratoire d'Analyse et de Mathmatiques Appliques) UPEM putu-harry.gunawan@univ.paris-est.fr Abstract Figure 1: Mangrove-Tsunami Model. The role of mangroves (coastal forests) in the mitigation of tsunami impacts is a debated topic

  14. Diffusion and Dispersion Characterization of a Numerical Tsunami Model

    E-Print Network [OSTI]

    Tolkova, Elena

    Diffusion and Dispersion Characterization of a Numerical Tsunami Model David Burwell, Elena Tolkova and Arun Chawla February 6, 2007 1 Introduction Method Of Splitting Tsunami (MOST) is a depth averaged long wave tsunami inundation model that was originally developed by Titov and Synolakis (1995) for 1D

  15. Query Based UML Modeling Validation and Verification of the System Model and

    E-Print Network [OSTI]

    Austin, Mark

    1 Query Based UML Modeling Validation and Verification of the System Model and Behavior. UML/SysML was designed to provide simple but powerful constructs for modeling a wide range of systems for a Hydraulic Crane Denny Mathew ENPM 643 System Validation and Verification Instructor: Dr. Mark Austin Fall

  16. Validation experiment of a numerically processed millimeter-wave interferometer in a laboratory

    SciTech Connect (OSTI)

    Kogi, Y., E-mail: kogi@fit.ac.jp; Higashi, T.; Matsukawa, S. [Department of Information Electronics, Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Mase, A. [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga, Fukuoka 816-0811 (Japan); Kohagura, J.; Yoshikawa, M. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Nagayama, Y.; Kawahata, K. [National Institute for Fusion Science, Toki, Gifu 509-5202 (Japan); Kuwahara, D. [Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan)

    2014-11-15

    We propose a new interferometer system for density profile measurements. This system produces multiple measurement chords by a leaky-wave antenna driven by multiple frequency inputs. The proposed system was validated in laboratory evaluation experiments. We confirmed that the interferometer generates a clear image of a Teflon plate as well as the phase shift corresponding to the plate thickness. In another experiment, we confirmed that quasi-optical mirrors can produce multiple measurement chords; however, the finite spot size of the probe beam degrades the sharpness of the resulting image.

  17. Validating the BHR RANS model for variable density turbulence

    SciTech Connect (OSTI)

    Israel, Daniel M [Los Alamos National Laboratory; Gore, Robert A [Los Alamos National Laboratory; Stalsberg - Zarling, Krista L [Los Alamos National Laboratory

    2009-01-01

    The BHR RANS model is a turbulence model for multi-fluid flows in which density variation plays a strong role in the turbulence processes. In this paper they demonstrate the usefulness of BHR over a wide range of flows which include the effects of shear, buoyancy, and shocks. The results are in good agreement with experimental and DNS data across the entire set of validation cases, with no need to retune model coefficients between cases. The model has potential application to a number of aerospace related flow problems.

  18. Experimentally validated finite element model of electrocaloric multilayer ceramic structures

    SciTech Connect (OSTI)

    Smith, N. A. S. E-mail: maciej.rokosz@npl.co.uk Correia, T. M. E-mail: maciej.rokosz@npl.co.uk; Rokosz, M. K. E-mail: maciej.rokosz@npl.co.uk

    2014-07-28

    A novel finite element model to simulate the electrocaloric response of a multilayer ceramic capacitor (MLCC) under real environment and operational conditions has been developed. The two-dimensional transient conductive heat transfer model presented includes the electrocaloric effect as a source term, as well as accounting for radiative and convective effects. The model has been validated with experimental data obtained from the direct imaging of MLCC transient temperature variation under application of an electric field. The good agreement between simulated and experimental data, suggests that the novel experimental direct measurement methodology and the finite element model could be used to support the design of optimised electrocaloric units and operating conditions.

  19. EXPERIMENTAL CHARACTERIZATION AND NUMERICAL MODELING OF THERMAL AND ELECTROCHEMISTRY EFFECTS IN

    E-Print Network [OSTI]

    Kassegne, Samuel Kinde

    EXPERIMENTAL CHARACTERIZATION AND NUMERICAL MODELING OF THERMAL AND ELECTROCHEMISTRY EFFECTS IN 3D and Numerical Modeling of Thermal and Electrochemistry Effects in 3D Bionanoelectronics Platform by Neha

  20. 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...

  1. Statistical validation of engineering and scientific models : bounds, calibration, and extrapolation.

    SciTech Connect (OSTI)

    Dowding, Kevin J.; Hills, Richard Guy (New Mexico State University, Las Cruces, NM)

    2005-04-01

    Numerical models of complex phenomena often contain approximations due to our inability to fully model the underlying physics, the excessive computational resources required to fully resolve the physics, the need to calibrate constitutive models, or in some cases, our ability to only bound behavior. Here we illustrate the relationship between approximation, calibration, extrapolation, and model validation through a series of examples that use the linear transient convective/dispersion equation to represent the nonlinear behavior of Burgers equation. While the use of these models represents a simplification relative to the types of systems we normally address in engineering and science, the present examples do support the tutorial nature of this document without obscuring the basic issues presented with unnecessarily complex models.

  2. Foundation Heat Exchanger Model and Design Tool Development and Validation

    E-Print Network [OSTI]

    . Feasibility of foundation heat exchangers in ground source heat pump systems in the United States. ASHRAE Heat Exchangers for Residential Ground Source Heat Pump Systems - Numerical Modeling and Experimental. Fisher, J. Shonder, P. Im. 2010. Residential Ground Source Heat Pump Systems Utilizing Foundation Heat

  3. VALIDATION OF EROSION MODELING: PHYSICAL AND Mehrad Kamalzare1

    E-Print Network [OSTI]

    -3590 ABSTRACT The overall intent of this research is to develop numerical models of erosion of levees, dams is necessary for emergency plans for levee or dam breaches. Griffis, 2007 addressed the overall design and hydraulic shear stress. Xu and Zhang (2009) found that in addition to soil type, the degree of compaction

  4. Numerical

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shinesSolarNewsusceptometer under pressureNavyNumerical simulations of current

  5. 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.

  6. Note: Numerical simulation and experimental validation of accelerating voltage formation for a pulsed electron accelerator

    SciTech Connect (OSTI)

    Egorov, I.

    2014-06-15

    This paper describes the development of a computation model of a pulsed voltage generator for a repetitive electron accelerator. The model is based on a principle circuit of the generator, supplemented with the parasitics elements of the construction. Verification of the principle model was achieved by comparison of simulation with experimental results, where reasonable agreement was demonstrated for a wide range of generator load resistance.

  7. Validation of the SUNY Satellite Model in a Meteosat Evironment

    SciTech Connect (OSTI)

    Perez, R.; Schlemmer, J.; Renne, D.; Cowlin, S.; George, R.; Bandyopadhyay, B.

    2009-01-01

    The paper presents a validation of the SUNY satellite-to-irradiance model against four ground-truth stations from the Indian solar radiation network located in and around the province of Rajasthan, India. The SUNY model had initially been developed and tested to process US weather satellite data from the GOES series and has been used as part of the production of the US National Solar Resource Data Base (NSRDB). Here the model is applied to processes data from the European weather satellites Meteosat 5 and 7.

  8. Small Buoys for Energy Harvesting : Experimental and Numerical Modeling Studies

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Small Buoys for Energy Harvesting : Experimental and Numerical Modeling Studies St´ephan T. Grilli for wave energy harvesting (free-floating or slackly moored), to produce about 1 KW per unit at full scale-contained (water tight) resonating multiple-spar buoy (or Starspar), in which a longer central spar houses the LEG

  9. Thermodynamics cycle analysis and numerical modeling of thermoelastic cooling systems

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Thermodynamics cycle analysis and numerical modeling of thermoelastic cooling systems Suxin Qian level. However, a thermoelastic cooling system integrated with heat transfer fluid loops have not been;2012) (a.k.a. elastocaloric cooling). These solid-state cooling systems offer us alternatives to eliminate

  10. Small Buoys for Energy Harvesting : Experimental and Numerical Modeling Studies

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Small Buoys for Energy Harvesting : Experimental and Numerical Modeling Studies St´ephan T. Grilli, Inc., Cranston, RI, USA ABSTRACT We present the development and application of small buoy systems climates, of two new types of buoy systems equipped with an embedded Linear Electric Generator (LEG; made

  11. Numerical Modeling of Periodic Composite Media for Electromagnetic Shielding Application

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    on a conventional mixing theory, have served as the fundamentals for these techniques. In these formulationsNumerical Modeling of Periodic Composite Media for Electromagnetic Shielding Application Dagang Wu-difference time-domain (FDTD) method. The results are compared with conventional mixing theories and 3D Fourier

  12. Direct Numerical Simulations and Modeling of Jets in Crossflow

    E-Print Network [OSTI]

    Mahesh, Krishnan

    Direct Numerical Simulations and Modeling of Jets in Crossflow A THESIS SUBMITTED TO THE FACULTY. i #12;To my parents and my grandparents, and to Ramnath ii #12;Abstract Jets in crossflow are used to study the different aspects of round jets in a crossflow. The first problem studies

  13. Numerical Verification and Experimental Validation of Sliding Mode Control Design for

    E-Print Network [OSTI]

    Kearfott, R. Baker

    Thermal SOFC Models Andreas Rauh, Luise Senkel, Thomas D¨otschel , Harald Aschemann Chair of Mechatronics@inf.uni-due.de Abstract The design of reliable and robust control strategies for the automatized operation of SOFC systems for an SOFC system that is available at the Chair of Mechatronics at the University of Rostock. Keywords

  14. Robust design and model validation of nonlinear compliant micromechanisms.

    SciTech Connect (OSTI)

    Howell, Larry L. (Brigham Young University, Provo, UT); Baker, Michael Sean; Wittwer, Jonathan W. (Brigham Young University, Provo, UT)

    2005-02-01

    Although the use of compliance or elastic flexibility in microelectromechanical systems (MEMS) helps eliminate friction, wear, and backlash, compliant MEMS are known to be sensitive to variations in material properties and feature geometry, resulting in large uncertainties in performance. This paper proposes an approach for design stage uncertainty analysis, model validation, and robust optimization of nonlinear MEMS to account for critical process uncertainties including residual stress, layer thicknesses, edge bias, and material stiffness. A fully compliant bistable micromechanism (FCBM) is used as an example, demonstrating that the approach can be used to handle complex devices involving nonlinear finite element models. The general shape of the force-displacement curve is validated by comparing the uncertainty predictions to measurements obtained from in situ force gauges. A robust design is presented, where simulations show that the estimated force variation at the point of interest may be reduced from {+-}47 {micro}N to {+-}3 {micro}N. The reduced sensitivity to process variations is experimentally validated by measuring the second stable position at multiple locations on a wafer.

  15. Validation of thermal models for a prototypical MEMS thermal actuator.

    SciTech Connect (OSTI)

    Gallis, Michail A.; Torczynski, John Robert; Piekos, Edward Stanley; Serrano, Justin Raymond; Gorby, Allen D.; Phinney, Leslie Mary

    2008-09-01

    This report documents technical work performed to complete the ASC Level 2 Milestone 2841: validation of thermal models for a prototypical MEMS thermal actuator. This effort requires completion of the following task: the comparison between calculated and measured temperature profiles of a heated stationary microbeam in air. Such heated microbeams are prototypical structures in virtually all electrically driven microscale thermal actuators. This task is divided into four major subtasks. (1) Perform validation experiments on prototypical heated stationary microbeams in which material properties such as thermal conductivity and electrical resistivity are measured if not known and temperature profiles along the beams are measured as a function of electrical power and gas pressure. (2) Develop a noncontinuum gas-phase heat-transfer model for typical MEMS situations including effects such as temperature discontinuities at gas-solid interfaces across which heat is flowing, and incorporate this model into the ASC FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (3) Develop a noncontinuum solid-phase heat transfer model for typical MEMS situations including an effective thermal conductivity that depends on device geometry and grain size, and incorporate this model into the FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (4) Perform combined gas-solid heat-transfer simulations using Calore with these models for the experimentally investigated devices, and compare simulation and experimental temperature profiles to assess model accuracy. These subtasks have been completed successfully, thereby completing the milestone task. Model and experimental temperature profiles are found to be in reasonable agreement for all cases examined. Modest systematic differences appear to be related to uncertainties in the geometric dimensions of the test structures and in the thermal conductivity of the polycrystalline silicon test structures, as well as uncontrolled nonuniform changes in this quantity over time and during operation.

  16. Integrating Numerical Computation into the Modeling Instruction Curriculum

    E-Print Network [OSTI]

    Caballero, Marcos D; Aiken, John M; Douglas, Scott S; Scanlon, Erin M; Thoms, Brian; Schatz, Michael F

    2012-01-01

    We describe a way to introduce physics high school students with no background in programming to computational problem-solving experiences. Our approach builds on the great strides made by the Modeling Instruction reform curriculum. This approach emphasizes the practices of "Developing and using models" and "Computational thinking" highlighted by the NRC K-12 science standards framework. We taught 9th-grade students in a Modeling-Instruction-based physics course to construct computational models using the VPython programming environment. Numerical computation within the Modeling Instruction curriculum provides coherence among the curriculum's different force and motion models, links the various representations which the curriculum employs, and extends the curriculum to include real-world problems that are inaccessible to a purely analytic approach.

  17. On numerical considerations for modeling reactive astrophysical shocks

    SciTech Connect (OSTI)

    Papatheodore, Thomas L.; Messer, O. E. Bronson, E-mail: tpapathe@utk.edu, E-mail: bronson@ornl.gov [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States)

    2014-02-10

    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. 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. 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 models of Type Ia supernovae, including potential impacts on observables.

  18. A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

    2013-01-01

    of numerical weather prediction solar irradiance forecasts numerical weather prediction model for solar irradiance weather prediction for intra?day solar  forecasting in the 

  19. 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.

  20. 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.

  1. 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.

  2. Model Based Test Generation for Microprocessor Architecture Validation

    E-Print Network [OSTI]

    Minnesota, University of

    , Minneapolis, MN 55455 CESCA, Virginia Tech, Blacksburg, VA 24061 Validation Technology, Intel Corporation

  3. 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.

  4. 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.

  5. Modeling Fluid Flow in Natural Systems, Model Validation and Demonstration

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties - WAPAEnergy6-09.docAERMOD-PRIME, Units 4, 1,RidgeModel Fire|of|

  6. Global sea-salt modeling: Results and validation against multicampaign shipboard measurements

    E-Print Network [OSTI]

    Global sea-salt modeling: Results and validation against multicampaign shipboard measurements of sea-salt concentrations from five different campaigns are used to validate the sea-salt). The validity of the sea-salt parameterizations is tested by employing a global forecasting model and transport

  7. Numerical model of Electron Cyclotron Resonance Ion Source

    E-Print Network [OSTI]

    Mironov, V; Bondarchenko, A; Efremov, A; Loginov, V

    2015-01-01

    Important features of Electron Cyclotron Resonance Ion Source (ECRIS) operation are accurately reproduced with a numerical code. The code uses the particle-in-cell technique to model a dynamics of ions in ECRIS plasma. It is shown that gas dynamical ion confinement mechanism is sufficient to provide the ion production rates in ECRIS close to the experimentally observed values. Extracted ion currents are calculated and compared to the experiment for few sources. Changes in the extracted ion currents are obtained with varying the gas flow into the source chamber and the microwave power. Empirical scaling laws for ECRIS design are studied and the underlying physical effects are discussed.

  8. Numerical Modeling of Submarine Mass-Movement Generated Waves Using RANS Model

    E-Print Network [OSTI]

    Yim, Solomon C.

    Numerical Modeling of Submarine Mass-Movement Generated Waves Using RANS Model D. YUK and S. YIM model for predicting waves generated by nearshore submarine mass-movements is described. The model to coastal scientists and engineers for many years. Coastal wave generation due to submarine mass movement

  9. Numerical study on transient heat transfer under soil with plastic mulch in agriculture applications using a nonlinear finite element model

    E-Print Network [OSTI]

    De Castro, Carlos Armando

    2011-01-01

    In this paper is developed a simple mathematical model of transient heat transfer under soil with plastic mulch in order to determine with numerical studies the influence of different plastic mulches on the soil temperature and the evolutions of temperatures at different depths with time. The governing differential equations are solved by a Galerkin Finite Element Model, taking into account the nonlinearities due to radiative heat exchange between the soil surface, the plastic mulch and the atmosphere. The model was validated experimentally giving good approximation of the model to the measured data. Simulations were run with the validated model in order to determine the optimal combination of mulch optical properties to maximize the soil temperature with a Taguchi's analysis, proving that the material most used nowadays in Colombia is not the optimal and giving quantitative results of the properties the optimal mulch must possess.

  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. Radiative transfer model for contaminated slabs : experimental validations

    E-Print Network [OSTI]

    Andrieu, François; Schmitt, Bernard; Douté, Sylvain; Brissaud, Olivier

    2015-01-01

    This article presents a set of spectro-goniometric measurements of different water ice samples and the comparison with an approximated radiative transfer model. The experiments were done using the spectro-radiogoniometer described in Brissaud et al. (2004). The radiative transfer model assumes an isotropization of the flux after the second interface and is fully described in Andrieu et al. (2015). Two kind of experiments were conducted. First, the specular spot was closely investigated, at high angular resolution, at the wavelength of $1.5\\,\\mbox{\\mu m}$, where ice behaves as a very absorbing media. Second, the bidirectional reflectance was sampled at various geometries, including low phase angles on 61 wavelengths ranging from $0.8\\,\\mbox{\\mu m}$ to $2.0\\,\\mbox{\\mu m}$. In order to validate the model, we made a qualitative test to demonstrate the relative isotropization of the flux. We also conducted quantitative assessments by using a bayesian inversion method in order to estimate the parameters (e.g. sampl...

  12. Fracture Density Estimation Using Spectral Analysis of Reservoir Reflections: A Numerical Modeling Approach

    E-Print Network [OSTI]

    Pearce, Fred

    2003-01-01

    We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir

  13. An approach to model validation and model-based prediction -- polyurethane foam case study.

    SciTech Connect (OSTI)

    Dowding, Kevin J.; Rutherford, Brian Milne

    2003-07-01

    Enhanced software methodology and improved computing hardware have advanced the state of simulation technology to a point where large physics-based codes can be a major contributor in many systems analyses. This shift toward the use of computational methods has brought with it new research challenges in a number of areas including characterization of uncertainty, model validation, and the analysis of computer output. It is these challenges that have motivated the work described in this report. Approaches to and methods for model validation and (model-based) prediction have been developed recently in the engineering, mathematics and statistical literatures. In this report we have provided a fairly detailed account of one approach to model validation and prediction applied to an analysis investigating thermal decomposition of polyurethane foam. A model simulates the evolution of the foam in a high temperature environment as it transforms from a solid to a gas phase. The available modeling and experimental results serve as data for a case study focusing our model validation and prediction developmental efforts on this specific thermal application. We discuss several elements of the ''philosophy'' behind the validation and prediction approach: (1) We view the validation process as an activity applying to the use of a specific computational model for a specific application. We do acknowledge, however, that an important part of the overall development of a computational simulation initiative is the feedback provided to model developers and analysts associated with the application. (2) We utilize information obtained for the calibration of model parameters to estimate the parameters and quantify uncertainty in the estimates. We rely, however, on validation data (or data from similar analyses) to measure the variability that contributes to the uncertainty in predictions for specific systems or units (unit-to-unit variability). (3) We perform statistical analyses and hypothesis tests as a part of the validation step to provide feedback to analysts and modelers. Decisions on how to proceed in making model-based predictions are made based on these analyses together with the application requirements. Updating modifying and understanding the boundaries associated with the model are also assisted through this feedback. (4) We include a ''model supplement term'' when model problems are indicated. This term provides a (bias) correction to the model so that it will better match the experimental results and more accurately account for uncertainty. Presumably, as the models continue to develop and are used for future applications, the causes for these apparent biases will be identified and the need for this supplementary modeling will diminish. (5) We use a response-modeling approach for our predictions that allows for general types of prediction and for assessment of prediction uncertainty. This approach is demonstrated through a case study supporting the assessment of a weapons response when subjected to a hydrocarbon fuel fire. The foam decomposition model provides an important element of the response of a weapon system in this abnormal thermal environment. Rigid foam is used to encapsulate critical components in the weapon system providing the needed mechanical support as well as thermal isolation. Because the foam begins to decompose at temperatures above 250 C, modeling the decomposition is critical to assessing a weapons response. In the validation analysis it is indicated that the model tends to ''exaggerate'' the effect of temperature changes when compared to the experimental results. The data, however, are too few and to restricted in terms of experimental design to make confident statements regarding modeling problems. For illustration, we assume these indications are correct and compensate for this apparent bias by constructing a model supplement term for use in the model-based predictions. Several hypothetical prediction problems are created and addressed. Hypothetical problems are used because no guidance was provided concern

  14. Documentation of Hybrid Hydride Model for Incorporation into Moose-Bison and Validation Strategy.

    SciTech Connect (OSTI)

    Weck, Philippe F; Tikare, Veena; Schultz, Peter Andrew; Clark, B; Mitchell, J; Glazoff, Michael V.; Homer, Eric R.

    2014-10-01

    This report documents the development, demonstration and validation of a mesoscale, microstructural evolution model for simulation of zirconium hydride ?-ZrH{sub 1.5} precipitation in the cladding of used nuclear fuels that may occur during long-term dry storage. While the Zr-based claddings are manufactured free of any hydrogen, they absorb hydrogen during service, in the reactor by a process commonly termed ‘hydrogen pick-up’. The precipitation and growth of zirconium hydrides during dry storage is one of the most likely fuel rod integrity failure mechanisms either by embrittlement or delayed hydride cracking of the cladding (Hanson et al., 2011). While the phenomenon is well documented and identified as a potential key failure mechanism during long-term dry storage (Birk et al., 2012 and NUREG/CR-7116), the ability to actually predict the formation of hydrides is poor. The model being documented in this work is a computational capability for the prediction of hydride formation in different claddings of used nuclear fuels. This work supports the Used Fuel Disposition Research and Development Campaign in assessing the structural engineering performance of the cladding during and after long-term dry storage. In this work, a model to numerically simulate hydride precipitation at the microstructural scale, in a wide variety of Zr-based claddings, under dry-storage conditions is being developed. It will be used to aid in the evaluation of the mechanical integrity of used fuel rods during dry storage and transportation by providing the structural conditions from the microstructural scale to the continuum scale to engineering component scale models to predict if the used fuel rods will perform without failure under normal and off-normal conditions. The microstructure, especially, the hydride structure is thought to be a primary determinant of cladding failure, thus this component of UFD’s storage and transportation analysis program is critical. The model development, application and validation of the model are documented and the limitations of the current model are discussed. The model has been shown to simulate hydride precipitation in Zircaloy-4 cladding with correct morphology, thermodynamics and kinetics. An unexpected insight obtained from simulations hydride formation in Zircaloy-4 is that small (sub-micron) precipitates need to order themselves to form the larger hydrides typically described as radially-reoriented precipitates. A limitation of this model is that it does not currently solve the stress state that forms dynamically in the precipitate or matrix surrounding the precipitate. A method to overcome the limitations is suggested and described in detail. The necessary experiments to provide key materials physics and to validate the model are also recommended.

  15. Numeric modeling of fire suppression by organophosphorous inhibitors

    E-Print Network [OSTI]

    Makhviladze, G M; Zykov, A P

    2008-01-01

    Numerical calculations of the effect of organophosphorous inhibitor (CF3CH2O)3P and its mixtures with carbon dioxide on propane flames are carried out using the three dimensional Reynolds-averaged Navier-Stokes (RANS) equations in the low Mach number approximation. The k-e model of turbulence, the EDC combustion model and the weighted-sum-of-gray-gases model of radiation are used. The Westbrook global-kinetic scheme with fractional order of reaction was used for the calculation of chemical reaction rate of propane combustion. The empirical expression for the correction factor for the chemical reaction rate was used to model the effect of organophosphorous inhibitor no the reaction. Two series of test calculations for different values of the correction factor are carried out. Dependences of the minimum extinguishing concentration of the inhibitor per carbon dioxide volume concentration in the extinguishing mixtures were obtained. The results of test calculations are shown to agree reasonably with the experimen...

  16. A numerical model of aerosol scavenging: Part 1, Microphysics parameterization

    SciTech Connect (OSTI)

    Molenkamp, C.R.; Bradley, M.M.

    1991-09-01

    We have developed a three-dimensional numerical model (OCTET) to simulate the dynamics and microphysics of clouds and the transport, diffusion and precipitation scavenging of aerosol particles. In this paper we describe the cloud microphysics and scavenging parameterizations. The representation of cloud microphysics is a bulk- water parameterization which includes water vapor and five types of hydrometeors (cloud droplets, rain drops, ice crystals, snow, and graupel). A parallel parameterization represents the scavenging interactions between pollutant particles and hydrometeors including collection of particles because of condensation nucleation, Brownian and phoretic attachment, and inertial capture, resuspension because of evaporation and sublimation; and transfer interactions where particles collected by one type of hydrometeor are transferred to another type of freezing, melting, accretion, riming and autoconversion.

  17. Alaska North Slope Tundra Travel Model and Validation Study

    SciTech Connect (OSTI)

    Harry R. Bader; Jacynthe Guimond

    2006-03-01

    The Alaska Department of Natural Resources (DNR), Division of Mining, Land, and Water manages cross-country travel, typically associated with hydrocarbon exploration and development, on Alaska's arctic North Slope. This project is intended to provide natural resource managers with objective, quantitative data to assist decision making regarding opening of the tundra to cross-country travel. DNR designed standardized, controlled field trials, with baseline data, to investigate the relationships present between winter exploration vehicle treatments and the independent variables of ground hardness, snow depth, and snow slab thickness, as they relate to the dependent variables of active layer depth, soil moisture, and photosynthetically active radiation (a proxy for plant disturbance). Changes in the dependent variables were used as indicators of tundra disturbance. Two main tundra community types were studied: Coastal Plain (wet graminoid/moist sedge shrub) and Foothills (tussock). DNR constructed four models to address physical soil properties: two models for each main community type, one predicting change in depth of active layer and a second predicting change in soil moisture. DNR also investigated the limited potential management utility in using soil temperature, the amount of photosynthetically active radiation (PAR) absorbed by plants, and changes in microphotography as tools for the identification of disturbance in the field. DNR operated under the assumption that changes in the abiotic factors of active layer depth and soil moisture drive alteration in tundra vegetation structure and composition. Statistically significant differences in depth of active layer, soil moisture at a 15 cm depth, soil temperature at a 15 cm depth, and the absorption of photosynthetically active radiation were found among treatment cells and among treatment types. The models were unable to thoroughly investigate the interacting role between snow depth and disturbance due to a lack of variability in snow depth cover throughout the period of field experimentation. The amount of change in disturbance indicators was greater in the tundra communities of the Foothills than in those of the Coastal Plain. However the overall level of change in both community types was less than expected. In Coastal Plain communities, ground hardness and snow slab thickness were found to play an important role in change in active layer depth and soil moisture as a result of treatment. In the Foothills communities, snow cover had the most influence on active layer depth and soil moisture as a result of treatment. Once certain minimum thresholds for ground hardness, snow slab thickness, and snow depth were attained, it appeared that little or no additive effect was realized regarding increased resistance to disturbance in the tundra communities studied. DNR used the results of this modeling project to set a standard for maximum permissible disturbance of cross-country tundra travel, with the threshold set below the widely accepted standard of Low Disturbance levels (as determined by the U.S. Fish and Wildlife Service). DNR followed the modeling project with a validation study, which seemed to support the field trial conclusions and indicated that the standard set for maximum permissible disturbance exhibits a conservative bias in favor of environmental protection. Finally DNR established a quick and efficient tool for visual estimations of disturbance to determine when investment in field measurements is warranted. This Visual Assessment System (VAS) seemed to support the plot disturbance measurements taking during the modeling and validation phases of this project.

  18. Urban carbon dioxide cycles within the Salt Lake Valley: A multiplebox model validated by observations

    E-Print Network [OSTI]

    Ehleringer, Jim

    Urban carbon dioxide cycles within the Salt Lake Valley: A multiplebox model validated within Salt Lake Valley, Utah, USA. The model was forced by observed winds, soundingderived mixing depths, and ecosystem type. The model was validated using hourly CO2 mole fractions measured at five sites in the urban

  19. A Workflow for Parameter Calibration and and Model Validation in SST: Interim Report.

    SciTech Connect (OSTI)

    Pebay, Philippe Pierre; Wilke, Jeremiah J; Sargsyan, Khachik

    2014-12-01

    This brief report explains the method used for parameter calibration and model validation in SST/Macro and the set of tools and workflow developed for this purpose.

  20. Model Validation at the 204-MW New Mexico Wind Energy Center

    SciTech Connect (OSTI)

    Muljadi, E.; Butterfield, C. P.; Ellis, A.; Mechenbier, J.; Hochheimer, J.; Young, R.; Miller, N.; Delmerico, R.; Zavadil, R.; Smith, J. C.

    2006-06-01

    Poster for WindPower 2006 held June 4-7, 2006, in Pittsburgh, PA, describing model validation at the 204-MW New Mexico Wind Energy Center.

  1. An independent verification and validation of the Future Theater Level Model conceptual model

    SciTech Connect (OSTI)

    Hartley, D.S. III; Kruse, K.L.; Martellaro, A.J.; Packard, S.L.; Thomas, B. Jr.; Turley, V.K.

    1994-08-01

    This report describes the methodology and results of independent verification and validation performed on a combat model in its design stage. The combat model is the Future Theater Level Model (FTLM), under development by The Joint Staff/J-8. J-8 has undertaken its development to provide an analysis tool that addresses the uncertainties of combat more directly than previous models and yields more rapid study results. The methodology adopted for this verification and validation consisted of document analyses. Included were detailed examination of the FTLM design documents (at all stages of development), the FTLM Mission Needs Statement, and selected documentation for other theater level combat models. These documents were compared to assess the FTLM as to its design stage, its purpose as an analytical combat model, and its capabilities as specified in the Mission Needs Statement. The conceptual design passed those tests. The recommendations included specific modifications as well as a recommendation for continued development. The methodology is significant because independent verification and validation have not been previously reported as being performed on a combat model in its design stage. The results are significant because The Joint Staff/J-8 will be using the recommendations from this study in determining whether to proceed with develop of the model.

  2. Numerical Methods for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory

    E-Print Network [OSTI]

    Zhihao Ge; Ruihua Li

    2015-03-08

    In the work, the numerical methods are designed for the Bogoliubov-Tolmachev-Shirkov model in superconductivity theory. The numerical methods are novel and effective to determine the critical transition temperature and approximate to the energy gap function of the above model. Finally, a numerical example confirming the theoretical results is presented.

  3. NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS

    E-Print Network [OSTI]

    NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS. Special focus is posed on the numerical solution algorithms for the saturation equation, which. The general background for the reservoir ow model is reviewed, and the main features of the numerical

  4. NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS

    E-Print Network [OSTI]

    NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS focus is posed on the numerical solution algorithms for the saturation equation, which is a convection­ eral background for the reservoir flow model is reviewed, and the main features of the numerical

  5. Adaptive Cruise Control: Experimental Validation of Advanced Controllers on Scale-Model Cars

    E-Print Network [OSTI]

    Ames, Aaron

    Adaptive Cruise Control: Experimental Validation of Advanced Controllers on Scale-Model Cars Aakar of correctness. In particular, safety constraints--maintaining a valid following distance from a lead car objectives in an optimal fashion. This methodology is demonstrated on scale-model cars, for which the CBF

  6. Adaptation and Validation of an Agent Model of Functional State and Performance for Individuals

    E-Print Network [OSTI]

    Treur, Jan

    functional state model to the individual and validation of the resulting model. First, human experiments have mostly qualitative theories from Psychology, but was not validated yet using human experiments been performed by taking a number of steps. First of all, an experiment with 31 human subjects has been

  7. Experimental identification and validation of an electrochemical model of a Lithium-Ion Battery

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Experimental identification and validation of an electrochemical model of a Lithium-Ion Battery an experimental parameter iden- tification and validation for an electrochemical lithium-ion battery model. The identification procedure is based on experimental data collected from a 6.8 Ah lithium-ion battery during charge

  8. ITER predictions using the GYRO verified and experimentally validated trapped gyro-Landau fluid transport model

    E-Print Network [OSTI]

    Budny, Robert

    predictions using the GYRO verified and experimentally validated trapped gyro-Landau fluid transport model JITER predictions using the GYRO verified and experimentally validated trapped gyro-Landau fluid transport model This article has been downloaded from IOPscience. Please scroll down to see the full text

  9. Aalborg Universitet Modelling and Validation of Water Hydration of PEM Fuel Cell Membrane in Dynamic

    E-Print Network [OSTI]

    Liso, Vincenzo

    Aalborg Universitet Modelling and Validation of Water Hydration of PEM Fuel Cell Membrane of Water Hydration of PEM Fuel Cell Membrane in Dynamic Operations. In ECS Transactions. (Vol. 68). ECS from vbn.aau.dk on: november 29, 2015 #12;Modelling and Validation of Water Hydration of PEM Fuel Cell

  10. Development of a Hydraulic Manipulator Servoactuator Model: Simulation and Experimental Validation

    E-Print Network [OSTI]

    Papadopoulos, Evangelos

    Development of a Hydraulic Manipulator Servoactuator Model: Simulation and Experimental Validation Abstract In this paper, modelling and identification of a hydraulic servoactuator system is presented, leakage, and load dynamics. System parameters are identified based on a high-performance hydraulic

  11. A regional numerical ocean model of the circulation in the Bay of Biscay

    E-Print Network [OSTI]

    Drijfhout, Sybren

    A regional numerical ocean model of the circulation in the Bay of Biscay Y. Friocourt,1,2,3 B Peninsula and in the Bay of Biscay is investigated by means of a regional ocean model. In particular numerical ocean model of the circulation in the Bay of Biscay, J. Geophys. Res., 112, C09008, doi:10

  12. Experimental and Numerical Investigations of Nonlinearity in soils using Advanced Laboratory-Scaled models

    E-Print Network [OSTI]

    ENINALS Experimental and Numerical Investigations of Nonlinearity in soils using Advanced of Nonlinearity in Soils Using Advanced Laboratory-scaled Models Concluding Workshop Ispra, May 28-30 2013 IFSTTAR-geological constraints - centrifuge modelling - numerical modelling MILESTONES - Experiencing techniques for realising

  13. NUMERICAL MODELLING OF IMPACT NOISE Cristina Daz Cereceda | Laboratori de Clcul Numric | Universitat Politcnica de Catalunya

    E-Print Network [OSTI]

    Huerta, Antonio

    NUMERICAL MODELLING OF IMPACT NOISE Cristina Díaz Cereceda | Laboratori de Càlcul Numèric Modelling of Impact Noise. In Congreso de Métodos Numéricos en Ingeniería 2009. [2] J. Hetherington, J. Poblet-Puig, A. Rodríguez-Ferran. Numerical Modelling of Impact Noise in Lightweight Floors: a Modal

  14. Development and validation of instantaneous risk model in nuclear power plant's risk monitor

    SciTech Connect (OSTI)

    Wang, J.; Li, Y.; Wang, F.; Wang, J.; Hu, L.

    2012-07-01

    The instantaneous risk model is the fundament of calculation and analysis in a risk monitor. This study focused on the development and validation of an instantaneous risk model. Therefore the principles converting from the baseline risk model to the instantaneous risk model were studied and separated trains' failure modes modeling method was developed. The development and validation process in an operating nuclear power plant's risk monitor were also introduced. Correctness of instantaneous risk model and rationality of converting method were demonstrated by comparison with the result of baseline risk model. (authors)

  15. Numerical Modeling of CIGS Solar Cells: Definition of the Baseline and

    E-Print Network [OSTI]

    Sites, James R.

    Thesis Numerical Modeling of CIGS Solar Cells: Definition of the Baseline and Explanation our supervision by Markus Gloeckler entitled "Numerical Modeling of CIGS Solar Cells: Definition. A three-layer structure, simulating a Cu(InGa)Se2 (CIGS) heterojunction solar cell, was set up using

  16. NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE

    E-Print Network [OSTI]

    Sites, James R.

    NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE M. Gloeckler, A important complications that are often found in experimental CIGS and CdTe solar cells. 1. INTRODUCTION Numerical modeling of polycrystalline thin-film solar cells is an important strategy to test the viability

  17. Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources

    E-Print Network [OSTI]

    Stutzmann, Eléonore

    Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise), Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources in seismic noise, body waves present appealing properties but are still challenging to extract. Here we first

  18. CONVERGENCE OF NUMERICAL APPROXIMATIONS TO A PHASE FIELD BENDING ELASTICITY MODEL OF

    E-Print Network [OSTI]

    CONVERGENCE OF NUMERICAL APPROXIMATIONS TO A PHASE FIELD BENDING ELASTICITY MODEL OF MEMBRANE, Number 1, Pages 1­18 CONVERGENCE OF NUMERICAL APPROXIMATIONS TO A PHASE FIELD BENDING ELASTICITY MODEL OF MEMBRANE DEFORMATIONS QIANG DU AND XIAOQIANG WANG This paper is dedicated to Prof.Max Gunzburger

  19. Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters

    E-Print Network [OSTI]

    Lee, Zhongping

    Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal waters (2005), Penetration of solar radiation in the upper ocean: A numerical model for oceanic and coastal; Siegel et al., 1995] have demonstrated that the penetration of EVIS in the upper layer of the ocean plays

  20. Numerical modeling of fluid flow and time-lapse seismics to monitor CO2

    E-Print Network [OSTI]

    Santos, Juan

    Numerical modeling of fluid flow and time-lapse seismics to monitor CO2 Sequestration in aquifers J, ITALY). IMAL, 30/5/2014 Numerical modeling of fluid flow and time-lapse seismics to monitor CO2 Sequestration in aquifers ­ p. #12;Introduction. I Storage of CO2 in geological formations is a procedure

  1. Numerical Model of a Tensioner System and Flex Joint 

    E-Print Network [OSTI]

    Huang, Han

    2013-07-27

    D will be integrated into a numerical code, known as COUPLE, for the simulation of the dynamic interaction among the hull of a floating structure, such as SPAR or TLP, its mooring system and riser system under the impact of wind, current and waves...

  2. Efficient numerical algorithms for surface formulations of mathematical models for biomolecule analysis and design

    E-Print Network [OSTI]

    Bardhan, Jaydeep Porter, 1978-

    2006-01-01

    This thesis presents a set of numerical techniques that extend and improve computational modeling approaches for biomolecule analysis and design. The presented research focuses on surface formulations of modeling problems ...

  3. Mathematical Models and Numerical Solutions of Liquid-Solid and Solid-Liquid Phase Change

    E-Print Network [OSTI]

    Surana, Karan S.; Joy, Aaron; Quiros, Luis; Reddy, JN

    2015-04-01

    This paper presents numerical simulations of liquid-solid and solid-liquid phase change processes using mathematical models in Lagrangian and Eulerian descriptions. The mathematical models are derived by assuming a smooth ...

  4. Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part I: Numerical Modeling

    E-Print Network [OSTI]

    Xu, Xianfan

    Thermoelectric Generators for Automotive Waste Heat Recovery Systems Part I: Numerical Modeling (TEG) designed for automotive waste heat recovery systems. This model is capable of computing telluride TEMs. Key words: Thermoelectric generators, waste heat recovery, automotive exhaust, skutterudites

  5. Modelling of Melt Damage of Tungsten Armour under Multiple Transients Expected in ITER and Validations Against JET-ILW Experiments

    E-Print Network [OSTI]

    Modelling of Melt Damage of Tungsten Armour under Multiple Transients Expected in ITER and Validations Against JET-ILW Experiments

  6. Validity of the WEPP model for predicting infiltration on irrigated lands 

    E-Print Network [OSTI]

    Ngang, Fidelis Ndemah

    1995-01-01

    The objective of this research was to establish the validity of the hydrologic component of the YVEPP erosion model for predicting infiltration on irrigated lands. WEPP uses the Green and Ampt equation with ponding to compute infiltration...

  7. BRE large compartment fire tests – characterising post-flashover fires for model validation 

    E-Print Network [OSTI]

    Welch, Stephen; Jowsey, Allan; Deeny, Susan; Morgan, Richard; Torero, Jose L

    2007-01-01

    Reliable and comprehensive measurement data from large-scale fire tests is needed for validation of computer fire models, but is subject to various uncertainties, including radiation errors in temperature measurement. Here, ...

  8. Vehicle Technologies Office Merit Review 2014: Validation of Material Models for Automotive Carbon Fiber Composite Structures

    Broader source: Energy.gov [DOE]

    Presentation given by General Motors at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about validation of material models...

  9. Climatically Diverse Data Set for Flat-Plate PV Module Model Validations (Presentation)

    SciTech Connect (OSTI)

    Marion, B.

    2013-05-01

    Photovoltaic (PV) module I-V curves were measured at Florida, Colorado, and Oregon locations to provide data for the validation and development of models used for predicting the performance of PV modules.

  10. Investigation of Wave Energy Converter Effects on Near-shore Wave Fields: Model Generation Validation and Evaluation - Kaneohe Bay HI.

    SciTech Connect (OSTI)

    Roberts, Jesse D.; Chang, Grace; Jones, Craig

    2014-09-01

    The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.

  11. Fractional Calculus in Hydrologic Modeling: A Numerical Perspective

    SciTech Connect (OSTI)

    David A. Benson; Mark M. Meerschaert; Jordan Revielle

    2012-01-01

    Fractional derivatives can be viewed either as a handy extension of classical calculus or, more deeply, as mathematical operators defined by natural phenomena. This follows the view that the diffusion equation is defined as the governing equation of a Brownian motion. In this paper, we emphasize that fractional derivatives come from the governing equations of stable Levy motion, and that fractional integration is the corresponding inverse operator. Fractional integration, and its multi-dimensional extensions derived in this way, are intimately tied to fractional Brownian (and Levy) motions and noises. By following these general principles, we discuss the Eulerian and Lagrangian numerical solutions to fractional partial differential equations, and Eulerian methods for stochastic integrals. These numerical approximations illuminate the essential nature of the fractional calculus.

  12. A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation and first results

    E-Print Network [OSTI]

    Spiga, Aymeric

    A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation) Mesoscale Model is a new versatile simulator of the Martian atmosphere and environment at horizontal scales, and photochemistry cycles. Since LMD-GCM large-scale simulations are also used to drive the mesoscale model

  13. Retrievals of Carbon Dioxide from GOSAT: Validation, model comparison and approach development

    E-Print Network [OSTI]

    Retrievals of Carbon Dioxide from GOSAT: Validation, model comparison and approach development properties of aerosol and cirrus particles. 3. Model Comparison Retrievals of XCO2 were performed on cloud and compared to the CarbonTracker model. The retrieval averaging kernels were applied to Carbon

  14. Verification and validation benchmarks.

    SciTech Connect (OSTI)

    Oberkampf, William Louis; Trucano, Timothy Guy

    2007-02-01

    Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of achievement in V&V activities, how closely related the V&V benchmarks are to the actual application of interest, and the quantification of uncertainties related to the application of interest.

  15. Web-page on UrQMD Model Validation

    E-Print Network [OSTI]

    A. Galoyan; J. Ritman; V. Uzhinsky

    2006-05-18

    A WEB-page containing materials of comparing experimental data and UrQMD model calculations has been designed. The page provides its user with a variety of tasks solved with the help of the model, accuracy and/or quality of experimental data description, and so on. The page can be useful for new experimental data analysis, or new experimental research planning. The UrQMD model is cited in more than 272 publications. Only 44 of them present original calculations. Their main results on the model are presented on the page.

  16. Turbulent Supersonic Channel Flow: Direct Numerical Simulation and Modeling

    E-Print Network [OSTI]

    Heinz, Stefan

    modeling: the turbulence frequency production mechanism, wall damping effects on turbulence model frequency production mechanisms and wall damping effects may be explained very well on the basis, Chik w = wall viscosity = kinematic viscosity, = T = turbulent kinematic viscosity, Ck d = pressure

  17. Numerical Modeling At Dixie Valley Geothermal Area (Iovenitti...

    Open Energy Info (EERE)

    is needed to preserve the geochemical signature of the reservoir and . Finally, a new stress model is planned to be used for Dixie Valley, the model will utilize a boundary...

  18. Numerically Efficient Water Quality Modeling and Security Applications 

    E-Print Network [OSTI]

    Mann, Angelica

    2013-02-04

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.4 Summary of contributions . . . . . . . . . . . . . . . . . . . . . . . . 17 2 THE MERLION WATER QUALITY MODEL . . . . . . . . . . . . . . . . 20 2.1 Model development . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.2 Origin... tracking algorithm . . . . . . . . . . . . . . . . . . . . . . . . 24 2.3 Merlion water quality model . . . . . . . . . . . . . . . . . . . . . . . 31 2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 3 EFFICIENT MULTI...

  19. Qualifying geospatial workflow models for adaptive controlled validity and accuracy

    E-Print Network [OSTI]

    Stock, Kristin

    with additional metadata associated with the chosen datasets and the chosen sub-models is essential to help quality and sensitivity. A meta- model integrating metadata measures compatible with current standards, not only is GEOSS expected to enable the sharing of data and sensors, but it will also facilitate

  20. Spatial Statistical Procedures to Validate Input Data in Energy Models

    SciTech Connect (OSTI)

    Johannesson, G.; Stewart, J.; Barr, C.; Brady Sabeff, L.; George, R.; Heimiller, D.; Milbrandt, A.

    2006-01-01

    Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, economic trends, and other primarily non-energy related uses. Systematic collection of empirical data solely for regional, national, and global energy modeling has not been established as in the abovementioned fields. Empirical and modeled data relevant to energy modeling is reported and available at various spatial and temporal scales that might or might not be those needed and used by the energy modeling community. The incorrect representation of spatial and temporal components of these data sets can result in energy models producing misleading conclusions, especially in cases of newly evolving technologies with spatial and temporal operating characteristics different from the dominant fossil and nuclear technologies that powered the energy economy over the last two hundred years. Increased private and government research and development and public interest in alternative technologies that have a benign effect on the climate and the environment have spurred interest in wind, solar, hydrogen, and other alternative energy sources and energy carriers. Many of these technologies require much finer spatial and temporal detail to determine optimal engineering designs, resource availability, and market potential. This paper presents exploratory and modeling techniques in spatial statistics that can improve the usefulness of empirical and modeled data sets that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) predicting missing data, and (3) merging spatial data sets. In addition, we introduce relevant statistical software models commonly used in the field for various sizes and types of data sets.

  1. Numerical Simulation of Pulse-Tube Refrigerators: 1D model I.A. Lyulina1

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    of a piston, an aftercooler (AC), a regenerator, a cold heat exchanger (CHX), a tube, a hot heat exchanger numerical model has been introduced to study steady oscillatory heat and mass transfer in the tube section, numerical simulation, high resolution scheme 1 Introduction The pulse tube is a relatively new type

  2. Numerical modeling of extreme rogue waves generated by directional energy focusing

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Numerical modeling of extreme rogue waves generated by directional energy focusing Christophe that contributes to the generation of extreme waves, also known as rogue waves, in the ocean. To simulate and analyze this phenomenon, we generate extreme waves in a 3D numerical wave tank (NWT), by specifying

  3. Estimate of recharge from radiocarbon dating of groundwater and numerical flow and transport modeling

    E-Print Network [OSTI]

    Zhu, Chen

    of radioactive waste repositories. A case study of a regional aquifer in northeastern Arizona shows the rechargeEstimate of recharge from radiocarbon dating of groundwater and numerical flow and transport ages using a linked numerical 14 C transport and flow model while hydraulic conductivity values

  4. NUMERICAL MODELING OF COASTAL TSUNAMI DISSIPATION AND Stphan T. Grilli1

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    1 NUMERICAL MODELING OF COASTAL TSUNAMI DISSIPATION AND IMPACT Stéphan T. Grilli1 , Jeffrey C Tehranirad2 Recent observations of the coastal impact of large tsunamis (e.g., Indian Ocean 2004; Tohoku 2011) and related numerical and theoretical works have made it increasingly clear that tsunami waves arrive

  5. NUMERICAL MODELING OF COASTAL TSUNAMI IMPACT DISSIPATION Stphan T. Grilli1

    E-Print Network [OSTI]

    Kirby, James T.

    1 NUMERICAL MODELING OF COASTAL TSUNAMI IMPACT DISSIPATION AND IMPACT Stéphan T. Grilli1 , Jeffrey Tehranirad2 Recent observations of the coastal impact of large tsunamis (e.g., Indian Ocean 2004; Tohoku 2011) and related numerical and theoretical works have made it increasingly clear that tsunami waves arrive

  6. Implementation and Validation of the BHR Turbulence Model in...

    Office of Scientific and Technical Information (OSTI)

    density mixing in the KH, RT, and RM cases in an Eulerian framework 7. The primary motivation of the present work is to implement the BHR-2 turbulence model in the Arbitrary...

  7. Model Validation Using Simulated Data Swapna S. Gokhale 1 , Michael R. Lyu 2 , Kishor S. Trivedi 1

    E-Print Network [OSTI]

    Lyu, Michael R.

    , the complex­ ity of the real world data might obscure the properties of the reliability models which are based reliability models using rate­based simulation tech­ nique, and validated the models using the simulated data reliability models that might be revealed by validating these models using simpler data sets. Rate­based

  8. Numerical model for steel catenary riser on seafloor support 

    E-Print Network [OSTI]

    You, Jung Hwan

    2007-04-25

    of development of a simplified seafloor support model. This model simulates the seafloor-pipe interaction as a flexible pipe supported on a bed of springs. Constants for the soil springs were derived from finite element studies performed in a separate, parallel...

  9. Numerically Estimating Internal Models of Dynamic Virtual Objects

    E-Print Network [OSTI]

    Sekuler, Robert

    human subjects to manipulate a computer-animated virtual object. This virtual object (vO) was a high, human cognition, human information processing, ideal performer, internal model, virtual object, virtual, specifically how humans acquire an internal model of a dynamic virtual object. Our methodology minimizes

  10. Validity of the [ital t]-[ital J] model

    SciTech Connect (OSTI)

    Batista, C.D.; Aligia, A.A. (Comision Nacional de Energia Atomica, Centro Atomico Bariloche, 8400 Bariloche (Argentina))

    1993-08-01

    We have diagonalized exactly an effective Hamiltonian [ital H][sub eff] that describes the low-energy eigenstates of Cu[sub 4]O[sub 8] cluster with five holes. Projecting these eigenstates onto Zhang-Rice states we find that for total spin [ital S]=1/2, they have more than 90% of local singlet character for realistic parameters. This percentage depends on [ital S] and the symmetry of the states and is larger for the ground state. The fit of the energy levels using a model similar to the [ital t]-[ital J] model, is improved substantially if the model includes a term that combines a nearest-neighbor exchange with a next-nearest-neighbor hopping.

  11. THE FERNALD DOSIMETRY RECONSTRUCTION PROJECT Environmental Pathways -Models and Validation

    E-Print Network [OSTI]

    and Deposition Models . 19 Building Wake Effects and Plume Rise . 23 Resuspension of Particulates . . . . . 24 . . . . . . . . . . 26 Deposition Measurements Using Gummed Film 27 Soil Data for Locations Near the FMPC .. .. 28 Project Task 4 D. Particle-Size Distributions for Releases of Uranium and Thorium E. Meteorological Data

  12. Automated Validation and Verification of Process Models Darren C. Atkinson

    E-Print Network [OSTI]

    Noll, John

    In process programming, processes are modeled as pieces of software, and a process programming language, implementation, and maintenance of software processes [2]. One of the outgrowths of this line of research that resemble, and in some cases are derived from, conventional programming languages [3]. One advantage

  13. Seismic scattering attributes to estimate reservoir fracture density : a numerical modeling study

    E-Print Network [OSTI]

    Pearce, Frederick D. (Frederick Douglas), 1978-

    2003-01-01

    We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...

  14. NUMERICAL MODELING OF 3D ORGANIC SOLAR CELLS Presented to the

    E-Print Network [OSTI]

    Kassegne, Samuel Kinde

    .2 Physical Process in Polymer: Fullerene Build Heterojunction Solar CellsNUMERICAL MODELING OF 3D ORGANIC SOLAR CELLS _______________ A Thesis Presented to the Faculty Solar Cells by Anurag Kaushik Master of Science in Electrical Engineering San Diego State University

  15. Numerical modeling of elastic wave scattering by near-surface heterogeneities

    E-Print Network [OSTI]

    Al Muhaidib, Abdulaziz

    2013-01-01

    A perturbation method for elastic waves and numerical forward modeling are used to calculate the effects of seismic wave scattering from arbitrary shape shallow subsurface heterogeneities. Wave propagation is simulated ...

  16. Numerical Modelling of a Pulse Combustion Burner: Limiting Conditions of Stable

    E-Print Network [OSTI]

    Vuik, Kees

    Numerical Modelling of a Pulse Combustion Burner: Limiting Conditions of Stable Operation P.A. van in the burner system. Self-sustained pulse combustion and high-intensity sound waves result if the system

  17. Mass and charge flow in nanopores: numerical simulation via mesoscale models

    E-Print Network [OSTI]

    Cecconi, Fabio

    Mass and charge flow in nanopores: numerical simulation via mesoscale models Mauro Chinappi1 at nanoscale is here addressed via a recent developed mesoscale approach. In particular the flow

  18. 2D-Modelling of pellet injection in the poloidal plane: results of numerical tests

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    2D-Modelling of pellet injection in the poloidal plane: results of numerical tests P. Lalousis developed for computing the expansion of pellet-produced clouds in the poloidal plane. The expansion

  19. Observational and Numerical Modeling Studies of Turbulence on the Texas-Louisiana Continental Shelf 

    E-Print Network [OSTI]

    Zhang, Zheng

    2013-05-24

    ), dissipation rate of temperature variance (?), eddy diffusivity of temperature (?'t), and eddy diffusivity of density (?'p). Numerical models were also applied to test their capability of simulating these turbulence quantities. At site D, TKE, E, and ? were...

  20. A comparative analysis of numerical simulation and analytical modeling of horizontal well cyclic steam injection 

    E-Print Network [OSTI]

    Ravago Bastardo, Delmira Cristina

    2005-08-29

    The main objective of this research is to compare the performance of cyclic steam injection using horizontal wells based on the analytical model developed by Gunadi against that based on numerical simulation. For comparison, a common reservoir...

  1. P. Douillet S. Ouillon E. Cordier A numerical model for ne suspended sediment transport

    E-Print Network [OSTI]

    transport á Numerical model á Deposition á Erosion á New Caledonia Introduction In New Caledonia, where open-cast for cohesive particles (e.g., Nicholson and O'Connor 1986; Teisson 1991; Brenon and Le Hir 1999), around sand

  2. Seismic Scattering Attributes to Estimate Reservoir Fracture Density: A Numerical Modeling Study

    E-Print Network [OSTI]

    Pearce, Frederick Douglas

    We use a 3-D finite difference numerical model to generate synthetic seismograms from a simple fractured reservoir containing evenly-spaced, discrete, vertical fracture zones. The fracture zones are represented using a ...

  3. Numerical modeling of hydraulic fracture initiation and development

    E-Print Network [OSTI]

    2007-05-25

    Calculation scheme for modeling a hydraulic fracturing process: horizontal section of a ...... Jr., “Overview of current hydraulic fracturing design and treatment technology. .... A. A. Dobroskok, A. Ghassemi, and A. M. Linkov, “Extended structural ...

  4. NUMERICAL MODELING OF TURBULENT FLOW IN A COMBUSTION TUNNEL

    E-Print Network [OSTI]

    Ghoniem, A.F.

    2013-01-01

    1VJcDona·ld, H. (1979) Combustion r 1 iodeJ·ing in Two and1979) Practical Turbulent-Combustion Interaction Models forInternation on Combustors. Combustion The 17th Symposium

  5. Ductile fracture modeling : theory, experimental investigation and numerical verification

    E-Print Network [OSTI]

    Xue, Liang, 1973-

    2007-01-01

    The fracture initiation in ductile materials is governed by the damaging process along the plastic loading path. A new damage plasticity model for ductile fracture is proposed. Experimental results show that fracture ...

  6. Experimental Validation of Building Vibration Propagation Using a Four Story Laboratory Model

    E-Print Network [OSTI]

    White, Robert D.

    Experimental Validation of Building Vibration Propagation Using a Four Story Laboratory Model@acentech.com Robert D. White, Assistant Professor, Tufts University, Dept. of Mechanical Engineering, R vibration levels at each floor. Mathematical models of column, beam, and slab elements were developed

  7. Chapter 13: Model Validation CAPS -ARPS Version 4.0 295

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    on the solar angle in the surface energy budget equation. Mutually exclusive options such as the warm rain.g., total energy) to comparing model results with known exact solutions of the Navier- Stokes equations, the equations of motion of a viscous fluid. The exact solutions are particularly relevant to model validation

  8. Preliminary Validation Using in vivo Measures of a Macroscopic Electrical Model of the Heart

    E-Print Network [OSTI]

    Coudière, Yves

    Preliminary Validation Using in vivo Measures of a Macroscopic Electrical Model of the Heart Maxime Antipolis, France 2 National Institutes of Health, National Heart Lung and Blood Institute, Laboratory of the cardiac electrical activity in a canine heart coupled with simulations done using macroscopic models

  9. The EvacSim Pedestrian Evacuation Agent Model: Development and Validation Sen g Murphy12

    E-Print Network [OSTI]

    Sreenan, Cormac J.

    The EvacSim Pedestrian Evacuation Agent Model: Development and Validation Seán Óg Murphy12.brown@cs.ucc.ie, cjs@cs.ucc.ie Keywords: evacuation simulation, model evaluation, pedestrian, emergency, real time Abstract EvacSim is a multi-agent building evacuation simulation featuring pedestrian occupant agents

  10. Tsunami Generation by Submarine Mass Failure. I: Modeling, Experimental Validation, and Sensitivity Analyses

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Tsunami Generation by Submarine Mass Failure. I: Modeling, Experimental Validation, and Sensitivity with a two-dimensional 2D fully nonlinear potential flow FNPF model for tsunami generation by two idealized types of submarine mass failure SMF : underwater slides and slumps. These simulations feature rigid

  11. Numerical modeling and experimental validation of dynamic fracture events along weak planes

    E-Print Network [OSTI]

    Huerta, Antonio

    ], metallic materials [32], ceramic mate- rials [5], bimaterial systems in polymer matrix composites [35], metal matrix com- posites [10], fiber reinforced plastic composites [9, 16], concrete [29], functionally

  12. A robotic crawler exploiting directional frictional interactions: experiments, numerics, and derivation of a reduced model

    E-Print Network [OSTI]

    Giovanni Noselli; Antonio DeSimone

    2014-08-26

    We present experimental and numerical results for a model crawler which is able to extract net positional changes from reciprocal shape changes, i.e. 'breathing-like' deformations, thanks to directional, frictional interactions with a textured solid substrate, mediated by flexible inclined feet. We also present a simple reduced model that captures the essential features of the kinematics and energetics of the gait, and compare its predictions with the results from experiments and from numerical simulations.

  13. Moist processes and the quasi-hydrostatic approximation in a mesoscale numerical model 

    E-Print Network [OSTI]

    Kennedy, Charles Joseph

    1987-01-01

    MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1987 Major Subject: Meteorology MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Approved as to style and content by: Dusan Djuric (Chair...

  14. Numerical modeling of the wind flow over a transverse dune

    E-Print Network [OSTI]

    Ascânio D. Araújo; Eric J. R. Parteli; Thorsten Poeschel; José S. Andrade Jr.; Hans J. Herrmann

    2013-09-30

    Transverse dunes, which form under unidirectional winds and have fixed profile in the direction perpendicular to the wind, occur on all celestial objects of our solar system where dunes have been detected. Here we perform a numerical study of the average turbulent wind flow over a transverse dune by means of computational fluid dynamics simulations. We find that the length of the zone of recirculating flow at the dune lee --- the {\\em{separation bubble}} --- displays a surprisingly strong dependence on the wind shear velocity, $u_{\\ast}$: it is nearly independent of $u_{\\ast}$ for shear velocities within the range between $0.2\\,$m$$s and $0.8\\,$m$$s but increases linearly with $u_{\\ast}$ for larger shear velocities. Our calculations show that transport in the direction opposite to dune migration within the separation bubble can be sustained if $u_{\\ast}$ is larger than approximately $0.39\\,$m$$s, whereas a larger value of $u_{\\ast}$ (about $0.49\\,$m$$s) is required to initiate this reverse transport.

  15. Numerical modeling of the wind flow over a transverse dune

    E-Print Network [OSTI]

    Araújo, Ascânio D; Poeschel, Thorsten; Andrade, José S; Herrmann, Hans J

    2013-01-01

    Transverse dunes, which form under unidirectional winds and have fixed profile in the direction perpendicular to the wind, occur on all celestial objects of our solar system where dunes have been detected. Here we perform a numerical study of the average turbulent wind flow over a transverse dune by means of computational fluid dynamics simulations. We find that the length of the zone of recirculating flow at the dune lee --- the {\\em{separation bubble}} --- displays a surprisingly strong dependence on the wind shear velocity, $u_{\\ast}$: it is nearly independent of $u_{\\ast}$ for shear velocities within the range between $0.2\\,$m$$s and $0.8\\,$m$$s but increases linearly with $u_{\\ast}$ for larger shear velocities. Our calculations show that transport in the direction opposite to dune migration within the separation bubble can be sustained if $u_{\\ast}$ is larger than approximately $0.39\\,$m$$s, whereas a larger value of $u_{\\ast}$ (about $0.49\\,$m$$s) is required to initiate this reverse transport.

  16. Numerical models of pressure pulse generation by imploding metal liners

    SciTech Connect (OSTI)

    Humphries, S. Jr. [Acceleration Associates, Albuquerque, NM (United States)] [Acceleration Associates, Albuquerque, NM (United States); [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Electrical Engineering; Ekdahl, C.A. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States)

    1996-12-01

    The authors describe numerical calculations of pressure pulse generation using imploding liners. Liners are metal cylinders that are magnetically compressed by an intense axial current flow from a high-power pulse generator. The simulations cover the acceleration of the liner, collision with an internal diagnostic target, followed by compression and shock wave heating of the target. With the projected current waveform of the Atlas capacitor bank (in development at Los Alamos National Laboratory), initial results suggest that it may be possible to achieve pressures exceeding 3,000 Gpa (30 Mbar) in a 4 mm diameter sample over an interval of 100--200 ns. The simulations were carried out with Crunch, a new one-dimensional hydrodynamics package for advanced personal computers. The program uses finite-element techniques to solve the coupled problems of hydrodynamics and magnetic diffusion. Crunch fully supports loading and interpolating Sesame equation-of-state tables. The program exhibits excellent stability, even for collisions between material shells and shock convergence on axis. In contrast to previous work, the present studies follow the full process through solid target collision and compression. The work supports the High-Energy Density Physics Program of Los Alamos National Laboratory (LANL), a component of the US Department of Energy Stockpile Stewardship Program. The purpose of this program is maintenance of the nuclear weapons stockpile through improved computational ability and above-ground experiments. Imploding liners driven by conventional capacitor banks constitute a portion of the program to study matter at high pressure.

  17. Vibration Model Validation for Linear Collider Detector Platforms

    SciTech Connect (OSTI)

    Bertsche, Kirk; Amann, J.W.; Markiewicz, T.W.; Oriunno, M.; Weidemann, A.; White, G.; /SLAC

    2012-05-16

    The ILC and CLIC reference designs incorporate reinforced-concrete platforms underneath the detectors so that the two detectors can each be moved onto and off of the beamline in a Push-Pull configuration. These platforms could potentially amplify ground vibrations, which would reduce luminosity. In this paper we compare vibration models to experimental data on reinforced concrete structures, estimate the impact on luminosity, and summarize implications for the design of a reinforced concrete platform for the ILC or CLIC detectors.

  18. Microbial dormancy improves development and experimental validation of ecosystem model

    SciTech Connect (OSTI)

    Wang, Gangsheng; Jagadamma, Sindhu; Mayes, Melanie; Schadt, Christopher Warren; Steinweg, Jessica M; Gu, Lianhong; Post, Wilfred M

    2015-01-01

    Climate feedbacks from soils can result from environmental change followed by response of plant and microbial communities, and/or associated changes in nutrient cycling. Explicit consideration of microbial life history traits and functions may be necessary to predict climate feedbacks due to changes in the physiology and community composition of microbes and their associated effect on carbon cycling. Here, we enhanced the Microbial-Enzyme-mediated Decomposition (MEND) model by incorporating microbial dormancy and the ability to track multiple isotopes of carbon. We tested two versions of MEND, i.e., MEND with dormancy and MEND without dormancy, against long-term (270 d) lab incubations of four soils with isotopically-labeled substrates. MEND without dormancy adequately fitted multiple observations (total and 14C respiration, and dissolved organic carbon), but at the cost of significantly underestimating the total microbial biomass. The MEND with dormancy improved estimates of microbial biomass by 20 71% over the MEND without dormancy. We observed large differences for two fitted model parameters, the specific maintenance and growth rates for active microbes, depending on whether dormancy was considered. Together our model extrapolations of the incubation study show that long-term soil incubations with observations in multiple carbon pools are necessary to estimate both decomposition and microbial parameters. These efforts should provide essential support to future field- and global-scale simulations and enable more confident predictions of feedbacks between environmental change and carbon cycling.

  19. 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.

  20. IMPROVED NUMERICAL METHODS FOR MODELING RIVER-AQUIFER INTERACTION.

    SciTech Connect (OSTI)

    Tidwell, Vincent C.; Sue Tillery; Phillip King

    2008-09-01

    A new option for Local Time-Stepping (LTS) was developed to use in conjunction with the multiple-refined-area grid capability of the U.S. Geological Survey's (USGS) groundwater modeling program, MODFLOW-LGR (MF-LGR). The LTS option allows each local, refined-area grid to simulate multiple stress periods within each stress period of a coarser, regional grid. This option is an alternative to the current method of MF-LGR whereby the refined grids are required to have the same stress period and time-step structure as the coarse grid. The MF-LGR method for simulating multiple-refined grids essentially defines each grid as a complete model, then for each coarse grid time-step, iteratively runs each model until the head and flux changes at the interfacing boundaries of the models are less than some specified tolerances. Use of the LTS option is illustrated in two hypothetical test cases consisting of a dual well pumping system and a hydraulically connected stream-aquifer system, and one field application. Each of the hypothetical test cases was simulated with multiple scenarios including an LTS scenario, which combined a monthly stress period for a coarse grid model with a daily stress period for a refined grid model. The other scenarios simulated various combinations of grid spacing and temporal refinement using standard MODFLOW model constructs. The field application simulated an irrigated corridor along the Lower Rio Grande River in New Mexico, with refinement of a small agricultural area in the irrigated corridor.The results from the LTS scenarios for the hypothetical test cases closely replicated the results from the true scenarios in the refined areas of interest. The head errors of the LTS scenarios were much smaller than from the other scenarios in relation to the true solution, and the run times for the LTS models were three to six times faster than the true models for the dual well and stream-aquifer test cases, respectively. The results of the field application show that better estimates of daily stream leakage can be made with the LTS simulation, thereby improving the efficiency of daily operations for an agricultural irrigation system. ACKNOWLEDGEMENTSThe authors appreciatively acknowledge support for Sue Tillery provided by Sandia National Laboratories' through a Campus Executive Laboratory Directed Research and Development (LDRD) research project.Funding for this study was provided by Directed Research and Development (LDRD) research project.

  1. Numerical Solution of a Free-Boundary Problem for Percussive Deep Drilling Modeling by BEM

    E-Print Network [OSTI]

    Mikhailov, Sergey

    Numerical Solution of a Free-Boundary Problem for Percussive Deep Drilling Modeling by BEM S to a stationary-periodic quasi-static model of rock percus- sive deep drilling is presented. The rock is modeled. An auxiliary problem of stationary inden- tation of a rigid drill bit is considered first, where it is assumed

  2. A/C Model Development and Validation | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing ToolInternationalReportOffice | DepartmentVery1, in:QuarterlyA SolarAA ViewA/C Model

  3. Acoustics 2000 1 The Two Dimensional Numerical Modeling

    E-Print Network [OSTI]

    -difference methods have often been used. This report terms the wave equations suited to waves in fluids, acoustic, Sven Treitel, and Alford, 1976) but the acoustic wave equations have also been used for geophysical. Key features of the model at present are: (i) The use of acoustic wave equation (ii) Time domain

  4. 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.

  5. Numerical modelling and analysis of a room temperature magnetic

    E-Print Network [OSTI]

    and analysis of a room temperature magnetic refrigeration system Department: Fuel Cells and Solid State are separated by channels of a heat transfer fluid. The time-dependent model solves the momentum and continuity equations of the flow of the heat transfer fluid and the coupled energy equations of the heat transfer

  6. A Two Pressure Numerical Model of Two Fluid Mixing \\Lambda

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    fluid. The model is designed for the study of acceleration driven mixing layers in a chunk mix regime to the description of natural phenomena, as in meteorological temperature in­ version driven updrafts quantities directly, to close the system of equations. Closure is a physics level identity, independent

  7. NUMERICAL MODELING OF FLUID FLOW AND TIME-LAPSE ...

    E-Print Network [OSTI]

    gabriela

    CO2 injection operation at the Sleipner gas field in the North Sea, operated by Statoil ... The simultaneous flow of brine and CO2 is modeled with the Black-Oil formulation for ..... As water saturation is reduced, and the larger pores drained first, ...

  8. Numerical Modeling of Seafloor Interation with Steel Catenary Riser 

    E-Print Network [OSTI]

    You, Jung Hwan

    2012-10-19

    , and moment. Primary outputs from this model include the deflected shape of the riser pipe and bending moments along riser length. The code also provides the location of maximum trench depth and the position where the maximum bending moment occurs and any...

  9. THEACCURACY OF NUMERICAL MODELS FOR CONTINUUM STANLY STEINBERG

    E-Print Network [OSTI]

    Steinberg, Stanly

    Water Rain Evaporation Figure 1.1. A Lake These notes are directed towards students who have some modest of water in the lake. Water can enter and leave the lake by various means: rain; evaporation; rivers and how much error is there is solving the mathematical model. #12; 2 Lake Ground Ground Water Ground

  10. 2013 CEF RUN - PHASE 1 DATA ANALYSIS AND MODEL VALIDATION

    SciTech Connect (OSTI)

    Choi, A.

    2014-05-08

    Phase 1 of the 2013 Cold cap Evaluation Furnace (CEF) test was completed on June 3, 2013 after a 5-day round-the-clock feeding and pouring operation. The main goal of the test was to characterize the CEF off-gas produced from a nitric-formic acid flowsheet feed and confirm whether the CEF platform is capable of producing scalable off-gas data necessary for the revision of the DWPF melter off-gas flammability model; the revised model will be used to define new safety controls on the key operating parameters for the nitric-glycolic acid flowsheet feeds including total organic carbon (TOC). Whether the CEF off-gas data were scalable for the purpose of predicting the potential flammability of the DWPF melter exhaust was determined by comparing the predicted H{sub 2} and CO concentrations using the current DWPF melter off-gas flammability model to those measured during Phase 1; data were deemed scalable if the calculated fractional conversions of TOC-to-H{sub 2} and TOC-to-CO at varying melter vapor space temperatures were found to trend and further bound the respective measured data with some margin of safety. Being scalable thus means that for a given feed chemistry the instantaneous flow rates of H{sub 2} and CO in the DWPF melter exhaust can be estimated with some degree of conservatism by multiplying those of the respective gases from a pilot-scale melter by the feed rate ratio. This report documents the results of the Phase 1 data analysis and the necessary calculations performed to determine the scalability of the CEF off-gas data. A total of six steady state runs were made during Phase 1 under non-bubbled conditions by varying the CEF vapor space temperature from near 700 to below 300°C, as measured in a thermowell (T{sub tw}). At each steady state temperature, the off-gas composition was monitored continuously for two hours using MS, GC, and FTIR in order to track mainly H{sub 2}, CO, CO{sub 2}, NO{sub x}, and organic gases such as CH{sub 4}. The standard deviation of the average vapor space temperature during each steady state ranged from 2 to 6°C; however, those of the measured off-gas data were much larger due to the inherent cold cap instabilities in the slurry-fed melters. In order to predict the off-gas composition at the sampling location downstream of the film cooler, the measured feed composition was charge-reconciled and input into the DWPF melter off-gas flammability model, which was then run under the conditions for each of the six Phase 1 steady states. In doing so, it was necessary to perform an overall heat/mass balance calculation from the melter to the Off-Gas Condensate Tank (OGCT) in order to estimate the rate of air inleakage as well as the true gas temperature in the CEF vapor space (T{sub gas}) during each steady state by taking into account the effects of thermal radiation on the measured temperature (T{sub tw}). The results of Phase 1 data analysis and subsequent model runs showed that the predicted concentrations of H{sub 2} and CO by the DWPF model correctly trended and further bounded the respective measured data in the CEF off-gas by over predicting the TOC-to-H{sub 2} and TOC-to-CO conversion ratios by a factor of 2 to 5; an exception was the 7X over prediction of the latter at T{sub gas} = 371°C but the impact of CO on the off-gas flammability potential is only minor compared to that of H{sub 2}. More importantly, the seemingly-excessive over prediction of the TOC-to-H{sub 2} conversion by a factor of 4 or higher at T{sub gas} < ~350°C was attributed to the conservative antifoam decomposition scheme added recently to the model and therefore is considered a modeling issue and not a design issue. At T{sub gas} > ~350°C, the predicted TOC-to-H{sub 2} conversions were closer to but still higher than the measured data by a factor of 2, which may be regarded as adequate from the safety margin standpoint. The heat/mass balance calculations also showed that the correlation between T{sub tw} and T{sub gas} in the CEF vapor space was close to that of the ½ scale SGM, whose data were ta

  11. 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.

  12. 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.

  13. Predicting Solar Flares by Data Assimilation in Avalanche Models. I. Model Design and Validation

    E-Print Network [OSTI]

    Eric Bélanger; Alain Vincent; Paul Charbonneau

    2007-08-14

    Data assimilation techniques, developed in the last two decades mainly for weather prediction, produce better forecasts by taking advantage of both theoretical/numerical models and real-time observations. In this paper, we explore the possibility of applying the data-assimilation techniques known as 4D-VAR to the prediction of solar flares. We do so in the context of a continuous version of the classical cellular-automaton-based self-organized critical avalanche models of solar flares introduced by Lu and Hamilton (Astrophys. J., 380, L89, 1991). Such models, although a priori far removed from the physics of magnetic reconnection and magneto-hydrodynamical evolution of coronal structures, nonetheless reproduce quite well the observed statistical distribution of flare characteristics. We report here on a large set of data assimilation runs on synthetic energy release time series. Our results indicate that, despite the unpredictable (and unobservable) stochastic nature of the driving/triggering mechanism within the avalanche model, 4D-VAR succeeds in producing optimal initial conditions that reproduce adequately the time series of energy released by avalanches/flares. This is an essential first step towards forecasting real flares.

  14. Key challenges to model-based design : distinguishing model confidence from model validation

    E-Print Network [OSTI]

    Flanagan, Genevieve (Genevieve Elise Cregar)

    2012-01-01

    Model-based design is becoming more prevalent in industry due to increasing complexities in technology while schedules shorten and budgets tighten. Model-based design is a means to substantiate good design under these ...

  15. Numerical simulations used for a validity check on the laser induced photo-detachment diagnostic method in electronegative plasmas

    SciTech Connect (OSTI)

    Oudini, N.; Taccogna, F.; Aanesland, A.

    2014-06-15

    Laser photo-detachment is used as a method to measure or determine the negative ion density and temperature in electronegative plasmas. In essence, the method consists of producing an electropositive channel (negative ion free region) via pulsed laser photo-detachment within an electronegative plasma bulk. Electrostatic probes placed in this channel measure the change in the electron density. A second pulse might be used to track the negative ion recovery. From this, the negative ion density and temperature can be determined. We study the formation and relaxation of the electropositive channel via a two-dimensional Particle-In-Cell/Mote Carlo collision model. The simulation is mainly carried out in a Hydrogen plasma with an electronegativity of ??=?1, with a parametric study for ? up to 20. The temporal and spatial evolution of the plasma potential and the electron densities shows the formation of a double layer (DL) confining the photo-detached electrons within the electropositive channel. This DL evolves into two fronts that move in the opposite directions inside and outside of the laser spot region. As a consequence, within the laser spot region, the background and photo-detached electron energy distribution function relaxes/thermalizes via collisionless effects such as Fermi acceleration and Landau damping. Moreover, the simulations show that collisional effects and the DL electric field strength might play a non-negligible role in the negative ion recovery within the laser spot region, leading to a two-temperature negative ion distribution. The latter result might have important effects in the determination of the negative ion density and temperature from laser photo detachment diagnostic.

  16. Validation of a Hot Water Distribution Model Using Laboratory and Field Data

    SciTech Connect (OSTI)

    Backman, C.; Hoeschele, M.

    2013-07-01

    Characterizing the performance of hot water distribution systems is a critical step in developing best practice guidelines for the design and installation of high performance hot water systems. Developing and validating simulation models is critical to this effort, as well as collecting accurate input data to drive the models. In this project, the ARBI team validated the newly developed TRNSYS Type 604 pipe model against both detailed laboratory and field distribution system performance data. Validation efforts indicate that the model performs very well in handling different pipe materials, insulation cases, and varying hot water load conditions. Limitations of the model include the complexity of setting up the input file and long simulation run times. In addition to completing validation activities, this project looked at recent field hot water studies to better understand use patterns and potential behavioral changes as homeowners convert from conventional storage water heaters to gas tankless units. Based on these datasets, we conclude that the current Energy Factor test procedure overestimates typical use and underestimates the number of hot water draws. This has implications for both equipment and distribution system performance. Gas tankless water heaters were found to impact how people use hot water, but the data does not necessarily suggest an increase in usage. Further study in hot water usage and patterns is needed to better define these characteristics in different climates and home vintages.

  17. ARRAY OPTIMIZATION FOR TIDAL ENERGY EXTRACTION IN A TIDAL CHANNEL – A NUMERICAL MODELING ANALYSIS

    SciTech Connect (OSTI)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea

    2014-04-18

    This paper presents an application of a hydrodynamic model to simulate tidal energy extraction in a tidal dominated estuary in the Pacific Northwest coast. A series of numerical experiments were carried out to simulate tidal energy extraction with different turbine array configurations, including location, spacing and array size. Preliminary model results suggest that array optimization for tidal energy extraction in a real-world site is a very complex process that requires consideration of multiple factors. Numerical models can be used effectively to assist turbine siting and array arrangement in a tidal turbine farm for tidal energy extraction.

  18. Verification and validation of the decision analysis model for assessment of tank waste remediation system waste treatment strategies

    SciTech Connect (OSTI)

    Awadalla, N.G.; Eaton, S.C.F.

    1996-09-04

    This document is the verification and validation final report for the Decision Analysis Model for Assessment of Tank Waste Remediation System Waste Treatment Strategies. This model is also known as the INSIGHT Model.

  19. Mathematical formulation and numerical modeling of wax deposition in pipelines from enthalpyporosity approach

    E-Print Network [OSTI]

    Firoozabadi, Abbas

    Mathematical formulation and numerical modeling of wax deposition in pipelines from enthalpy in the layer composed of the two-phase wax and oil (that is the gel layer), and (3) use Fick's law to describe to temperature gradient. In this work, a rigorous math- ematical model for the prediction of wax deposition

  20. Intercomparison of Single-Column Numerical Models for the Prediction of Radiation Fog

    E-Print Network [OSTI]

    Intercomparison of Single-Column Numerical Models for the Prediction of Radiation Fog THIERRY-term forecasting of fog is a difficult issue that can have a large societal impact. Radiation fog appears layers of the atmosphere. Current NWP models poorly forecast the life cycle of fog, and improved NWP

  1. Modeling and Design of RF MEMS Structures Using Computationally Efficient Numerical Techniques

    E-Print Network [OSTI]

    Tentzeris, Manos

    Modeling and Design of RF MEMS Structures Using Computationally Efficient Numerical Techniques N. A Abstract The modeling of MEMS structures using MRTD is presented. Many complex RF structures have been communication systems efficiently and accurately. Specifically, micromachined structures such as MEMS

  2. NUMERICAL COUPLING OF ELECTRIC CIRCUIT EQUATIONS AND ENERGY-TRANSPORT MODELS FOR SEMICONDUCTORS

    E-Print Network [OSTI]

    Jüngel, Ansgar

    NUMERICAL COUPLING OF ELECTRIC CIRCUIT EQUATIONS AND ENERGY-TRANSPORT MODELS FOR SEMICONDUCTORS effects is proposed. The charged particle flow in the semiconductor devices is described by the energy-transport equations for the electrons and the drift-diffusion equations for the holes. The electric circuit is modeled

  3. VERIFICATION AND VALIDATION OF MODELS IN THE NATIONAL SCIENCE DIGITAL LIBRARY

    E-Print Network [OSTI]

    Stevenson, D. E. "Steve"

    VERIFICATION AND VALIDATION OF MODELS IN THE NATIONAL SCIENCE DIGITAL LIBRARY D. E. STEVENSON Abstract. The National Science Digital Library is the Nation's online library for education and re- search Science Digital Library in a Nutshell "The National Science Foundation's (NSF) National Science

  4. A Process Modelling Framework for Formal Validation of Panama Canal System Operations

    E-Print Network [OSTI]

    Austin, Mark

    1 A Process Modelling Framework for Formal Validation of Panama Canal System Operations John) and will even provide for continued operations while sections of the canal system are undergoing maintenance. Design for automation in large-scale system operations is challenging because in addition to making sure

  5. Calibration and validation of a non-point source pollution model

    E-Print Network [OSTI]

    Grunwald, Sabine

    Calibration and validation of a non-point source pollution model S. Grunwalda,* , L.D. Nortonb drainage behavior and sediment yield to develop management strategies for agricultural waters. The objective of this study was to investigate the performance of the Agricultural Non-Point Source Pollution

  6. VALIDATION OF PV PERFORMANCE MODELS USING SATELLITE-BASED IRRADIANCE MEASUREMENTS: A CASE STUDY

    E-Print Network [OSTI]

    Perez, Richard R.

    VALIDATION OF PV PERFORMANCE MODELS USING SATELLITE-BASED IRRADIANCE MEASUREMENTS: A CASE STUDY Clean Power Research Kirkland, WA e-mail: aparkins@cleanpower.com ABSTRACT Photovoltaic (PV) system and existing PV systems under a wide variety of environmental conditions. Ground based meteorological

  7. IEEE SSCI 2013 R.E. Marks 2013 Page 1 Tutorial: Validating Simulation Models, and

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    IEEE SSCI 2013 R.E. Marks 2013 Page 1 Tutorial: Validating Simulation Models, and Multi, and University of Melbourne robert.marks@gmail.com > #12;IEEE SSCI 2013 R.E. Marks 2013 Page 2 OUTLINE 1 in the social sciences," The Knowledge Engineering Review, 27(2): 123-136, 2012. #12;IEEE SSCI 2013 R

  8. MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu

    E-Print Network [OSTI]

    Li, Perry Y.

    MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu Center for Compact-speed on/off valves are a critical technology for enabling digital control of hydraulic systems via pulse-width- modulation (PWM). High-speed valves, when used in virtually variable displacement pumps (VVDP), increase

  9. Validating a model of colon colouration using an Evolution Strategy with adaptive approximations

    E-Print Network [OSTI]

    Rowe, Jon

    Validating a model of colon colouration using an Evolution Strategy with adaptive approximations light interaction with the tissue, is aimed at correlating the histology of the colon and its colours been applied to solve it. An adaptive approximate optimisation method has been developed and applied

  10. On the validity of dielectric continuum models in application to solvation in molecular solvents

    E-Print Network [OSTI]

    Matyushov, Dmitry

    On the validity of dielectric continuum models in application to solvation in molecular solvents simulations of solvation of a point dipole in dipolar­quadrupolar solvents of varying dipole moment and axial of a monotonic increase of the absolute value of the solvation chemical potential p with the solvent dielectric

  11. Development and Validation of an Advanced Stimulation Prediction Model for Enhanced Geothermal Systems (EGS)

    Broader source: Energy.gov [DOE]

    Project objectives: Develop a true 3D hydro-thermal fracturing and proppant flow/transport simulator that is particularly suited for EGS reservoir creation. Perform laboratory scale model tests of hydraulic fracturing and proppant flow/transport using a polyaxial loading device, and use the laboratory results to test and validate the 3D simulator.

  12. Model-Based Validation of an Intrusion-Tolerant Information System Fabrice Stevens

    E-Print Network [OSTI]

    Sanders, William H.

    , we describe a model-based validation effort that was undertaken as part of a unified approach was supported by DARPA contract number F30602-02-C- 0134. as mentioned above, it is practically impossible a se- cure system would have to represent, among other things, the attacker's behavior. Since some

  13. Development of SNL-SWAN, a Validated Wave Energy Converter Array Modeling Tool

    E-Print Network [OSTI]

    Siefert, Chris

    Development of SNL-SWAN, a Validated Wave Energy Converter Array Modeling Tool Kelley Ruehl#1 energy will lead to the necessary deployment of Wave Energy Converters (WECs) in arrays, or wave farms state dependent wave energy conversion of WECs. Keywords-- wave energy, wave farm, WEC array, SWAN

  14. MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu

    E-Print Network [OSTI]

    Li, Perry Y.

    MODELING AND VALIDATION OF A HIGH SPEED ROTARY PWM ON/OFF VALVE Haink C. Tu Center for Compact and Efficient Fluid Power Department of Mechanical Engineering University of Minnesota Minneapolis, Minnesota designed specifically for PWM. In comparison to con- ventional valves, the rotary valve reduces valve

  15. Effects of winds and Caribbean eddies on the frequency of Loop Current eddy shedding: A numerical model study

    E-Print Network [OSTI]

    Effects of winds and Caribbean eddies on the frequency of Loop Current eddy shedding: A numerical of Mexico, Caribbean Current, Loop Current, eddy shedding, winds and eddies, numerical ocean model Citation of Loop Current eddy shedding: A numerical model study, J. Geophys. Res., 108(C10), 3324, doi:10

  16. Generator Dynamic Model Validation and Parameter Calibration Using Phasor Measurements at the Point of Connection

    SciTech Connect (OSTI)

    Huang, Zhenyu; Du, Pengwei; Kosterev, Dmitry; Yang, Steve

    2013-05-01

    Disturbance data recorded by phasor measurement units (PMU) offers opportunities to improve the integrity of dynamic models. However, manually tuning parameters through play-back events demands significant efforts and engineering experiences. In this paper, a calibration method using the extended Kalman filter (EKF) technique is proposed. The formulation of EKF with parameter calibration is discussed. Case studies are presented to demonstrate its validity. The proposed calibration method is cost-effective, complementary to traditional equipment testing for improving dynamic model quality.

  17. Recovery Act. Development and Validation of an Advanced Stimulation Prediction Model for Enhanced Geothermal Systems

    SciTech Connect (OSTI)

    Gutierrez, Marte

    2013-12-31

    This research project aims to develop and validate an advanced computer model that can be used in the planning and design of stimulation techniques to create engineered reservoirs for Enhanced Geothermal Systems. The specific objectives of the proposal are to; Develop a true three-dimensional hydro-thermal fracturing simulator that is particularly suited for EGS reservoir creation; Perform laboratory scale model tests of hydraulic fracturing and proppant flow/transport using a polyaxial loading device, and use the laboratory results to test and validate the 3D simulator; Perform discrete element/particulate modeling of proppant transport in hydraulic fractures, and use the results to improve understand of proppant flow and transport; Test and validate the 3D hydro-thermal fracturing simulator against case histories of EGS energy production; and Develop a plan to commercialize the 3D fracturing and proppant flow/transport simulator. The project is expected to yield several specific results and benefits. Major technical products from the proposal include; A true-3D hydro-thermal fracturing computer code that is particularly suited to EGS; Documented results of scale model tests on hydro-thermal fracturing and fracture propping in an analogue crystalline rock; Documented procedures and results of discrete element/particulate modeling of flow and transport of proppants for EGS applications; and Database of monitoring data, with focus of Acoustic Emissions (AE) from lab scale modeling and field case histories of EGS reservoir creation.

  18. On the validity of drift-reduced fluid models for tokamak plasma simulation

    E-Print Network [OSTI]

    Leddy, Jarrod; Romanelli, Michele

    2015-01-01

    Drift-reduced plasma fluid models are commonly used in plasma physics for analytics and simulations; however, the validity of such models must be veri?ed for the regions of parameter space in which tokamak plasmas exist. By looking at the linear behaviour of drift-reduced and full-velocity models one can determine that the physics lost through the simplification that the drift-reduction provides is important in the core region of the tokamak. It is more acceptable for the edge-region but one must determine speci?cally for a given simulation if such a model is appropriate.

  19. Characterization of Texas lignite and numerical modeling of its in-situ gasification 

    E-Print Network [OSTI]

    Wang, Yih-Jy

    1983-01-01

    Modeling Site selection for in-situ gasification projects normally involves application of site screen1ng criteria. Some of these cr1teria were discussed by Russell et al. (1983). Numerical simulation may play an important role in s1te selection...CHARACTERIZATION OF TEXAS LIGNITE AND NUMERICAL MODELING OF ITS IN-SITU GASIFICATION A Thesis by YIH-JY WANG Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER...

  20. Validation of a Hot Water Distribution Model Using Laboratory and Field Data

    SciTech Connect (OSTI)

    Backman, C.; Hoeschele, M.

    2013-07-01

    Characterizing the performance of hot water distribution systems is a critical step in developing best practice guidelines for the design and installation of high performance hot water systems. Developing and validating simulation models is critical to this effort, as well as collecting accurate input data to drive the models. In this project, the Building America research team ARBI validated the newly developed TRNSYS Type 604 pipe model against both detailed laboratory and field distribution system performance data. Validation efforts indicate that the model performs very well in handling different pipe materials, insulation cases, and varying hot water load conditions. Limitations of the model include the complexity of setting up the input file and long simulation run times. This project also looked at recent field hot water studies to better understand use patterns and potential behavioral changes as homeowners convert from conventional storage water heaters to gas tankless units. The team concluded that the current Energy Factor test procedure overestimates typical use and underestimates the number of hot water draws, which has implications for both equipment and distribution system performance. Gas tankless water heaters were found to impact how people use hot water, but the data does not necessarily suggest an increase in usage. Further study in hot water usage and patterns is needed to better define these characteristics in different climates and home vintages.

  1. Thermal Modeling and Experimental Validation of Human Hair and Skin Heated by Broadband Light

    E-Print Network [OSTI]

    Aguilar, Guillermo

    distribution within the hair follicle is highly non-uniform: the minimum temperature occurs at the follicle Sun, PhD,1 Alex Chaney,1 Robert Anderson, PhD,2 and Guillermo Aguilar, PhD 1 * 1 Department:(a)determinetheoveralleffectofPPxonskinhumidi- tyandassociatedskinopticalproperties,and;(b)developaPT numerical model to study the spatial and temporal hair and skin temperature

  2. 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.

  3. The NINJA-2 project: Detecting and characterizing gravitational waveforms modelled using numerical binary black hole simulations

    E-Print Network [OSTI]

    :,; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endr?czi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N; Kim, N G; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I

    2014-01-01

    The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave astrophysics communities. The purpose of NINJA is to study the ability to detect gravitational waves emitted from merging binary black holes and recover their parameters with next-generation gravitational-wave observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete binary black hole hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a "blind injection challenge" similar to that conducted in recent LIGO and Virgo science runs, we added 7 hybrid waveforms to two months of data recolored to predictions of Advanced LIGO and Advanced Virgo sensitivity curves during their first observing runs. The resulting data was analyzed by gravitational-wave detection algorithms and 6 of the waveforms were recovered w...

  4. User's Manual for Data for Validating Models for PV Module Performance

    SciTech Connect (OSTI)

    Marion, W.; Anderberg, A.; Deline, C.; Glick, S.; Muller, M.; Perrin, G.; Rodriguez, J.; Rummel, S.; Terwilliger, K.; Silverman, T. J.

    2014-04-01

    This user's manual describes performance data measured for flat-plate photovoltaic (PV) modules installed in Cocoa, Florida, Eugene, Oregon, and Golden, Colorado. The data include PV module current-voltage curves and associated meteorological data for approximately one-year periods. These publicly available data are intended to facilitate the validation of existing models for predicting the performance of PV modules, and for the development of new and improved models. For comparing different modeling approaches, using these public data will provide transparency and more meaningful comparisons of the relative benefits.

  5. An examination of the construct validity of predictors of productive and counterproductive job performance using structural equation modeling 

    E-Print Network [OSTI]

    Tice, Julie Anne Goodwin

    1996-01-01

    This research used structural equation modeling to test the construct validity of measures I I ion, and work of four global constructs: trait socialization, self-concept, organizational socialization' concept. Using measurement model procedures...

  6. Numerical model for vibration damping resulting from the first-order phase transformations

    E-Print Network [OSTI]

    Melnik, Roderick

    : Martensite transformation; Thermo-mechanical coupling; Vibration damping; Ginzburg­Landau theory 1Numerical model for vibration damping resulting from the first-order phase transformations L Landau­Ginzburg theory that couples nonlinear mechanical and thermal fields. The free energy function

  7. Nonlinear inverse problem for a model of ion-exchange filter: numerical recovery of parameters

    E-Print Network [OSTI]

    methods of ion exchange is based on passing of source water or partially treated water through a filter-exchange filters results in highly mineralized, acidic and alkaline waste water [9]. With the continuous1 Nonlinear inverse problem for a model of ion-exchange filter: numerical recovery of parameters

  8. Numerical modeling of fluid flow and time-lapse seismograms applied to

    E-Print Network [OSTI]

    Santos, Juan

    ; and CO2 and CO2 are the CO2 mole fraction and the CO2 mass fraction in the brine phase. This conversionNumerical modeling of fluid flow and time-lapse seismograms applied to CO2 storage and monitoring G and time-lapse seismograms applied to CO2 storage and monitoring ­ p. #12;Introduction · Fossil

  9. Numerical analysis of electric field formulations of the eddy current model

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    Numerical analysis of electric field formulations of the eddy current model Alfredo Berm´udez1 methods for the numeri- cal solution of the eddy current problem in a bounded conducting domain crossed): 78M10, 65N30 Key words Low-frequency harmonic Maxwell equations, eddy currents, finite elements

  10. Mathematical and numerical analysis of a transient non-linear axisymmetric eddy current model

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    Mathematical and numerical analysis of a transient non-linear axisymmetric eddy current model the theoretically predicted behavior of the method, are reported. Keywords transient eddy current · axisymmetric is the accurate computation of power losses in the ferromagnetic components of the core due to hysteresis and eddy-current

  11. NUMERICAL SOLUTION OF A TRANSIENT NON-LINEAR AXISYMMETRIC EDDY CURRENT MODEL WITH NON-LOCAL

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    NUMERICAL SOLUTION OF A TRANSIENT NON-LINEAR AXISYMMETRIC EDDY CURRENT MODEL WITH NON@ing-mat.udec.cl This paper deals with an axisymmetric transient eddy current problem in conductive nonlinear magnetic media of the proposed scheme. Keywords: transient eddy current problem; electromagnetic losses; nonlinear magnetic

  12. A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness

    E-Print Network [OSTI]

    Nagy, Peter B.

    A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation, the path of the eddy current must follow a more tortuous route in the material, which produces a reduction

  13. 792 / JOURNAL OF ENVIRONMENTAL ENGINEERING / SEPTEMBER 1999 NUMERICAL MODEL OF SEDIMENTATION/THICKENING

    E-Print Network [OSTI]

    Wells, Scott A.

    792 / JOURNAL OF ENVIRONMENTAL ENGINEERING / SEPTEMBER 1999 NUMERICAL MODEL OF SEDIMENTATION with the ASCE Manager of Journals. The manuscript for this paper was submitted for review and possible publication on July 20, 1998. This paper is part of the Journal of Environmental Engineering, Vol. 125, No. 9

  14. Numerical and analytical modelling of entropy noise in a supersonic nozzle with a shock

    E-Print Network [OSTI]

    Nicoud, Franck

    Numerical and analytical modelling of entropy noise in a supersonic nozzle with a shock M. Leyko a these sources, the noise coming from the turbulent flame within the combustor is already identified in a supersonic nozzle with a shock, Journal of Sound and Vibration (2011), doi:10.1016/j.jsv.2011.01.025 #12;Two

  15. DROP-SCALE NUMERICAL MODELING OF CHEMICAL PARTITIOING DURING CLOUD HYDROMETEOR FREEZING

    E-Print Network [OSTI]

    Stuart, Amy L.

    DROP-SCALE NUMERICAL MODELING OF CHEMICAL PARTITIOING DURING CLOUD HYDROMETEOR FREEZING A.L. Stuart freezing provide greatly varying estimates of the retention efficiency of volatile solutes (e.g., Lamb understanding of the dependence of partitioning on chemical properties and freezing conditions (Stuart

  16. International Series of Numerical Mathematics, Vol. 160, 521540 Freezing of Living Cells: Mathematical Models

    E-Print Network [OSTI]

    Turova, Varvara

    International Series of Numerical Mathematics, Vol. 160, 521­540 Freezing of Living Cells, stresses arising due to non-simultaneous freezing of water in- side and outside of cells are modeled and outside of living cells during freezing is derived by applying an appropriate averaging technique

  17. COMPUTATIONAL CHALLENGES IN THE NUMERICAL TREATMENT OF LARGE AIR POLLUTION MODELS

    E-Print Network [OSTI]

    Ostromsky, Tzvetan

    COMPUTATIONAL CHALLENGES IN THE NUMERICAL TREATMENT OF LARGE AIR POLLUTION MODELS I. DIMOV , K. GEORGIEVy, TZ. OSTROMSKY , R. J. VAN DER PASz, AND Z. ZLATEVx Abstract. The air pollution, and especially the reduction of the air pollution to some acceptable levels, is an important environmental problem, which

  18. Ensemble Kalman Filter Data Assimilation in a 1D Numerical Model Used for Fog Forecasting

    E-Print Network [OSTI]

    Ensemble Kalman Filter Data Assimilation in a 1D Numerical Model Used for Fog Forecasting SAMUEL RE, a need exists for accurate and updated fog and low-cloud forecasts. Couche Brouillard Eau Liquide (COBEL for the very short-term forecast of fog and low clouds. This forecast system assimilates local observations

  19. A faster numerical scheme for a coupled system modelling soil erosion and sediment transport

    E-Print Network [OSTI]

    d'Orléans, Université

    A faster numerical scheme for a coupled system modelling soil erosion and sediment transport M flow and the bed sediment, are classically described by a well-established system coupling the shallow states and the positivity of both water depth and sediment concentration. Recently, finite volume schemes

  20. Mathematical, physical and numerical principles essential for models of turbulent mixing

    SciTech Connect (OSTI)

    Sharp, David Howland [Los Alamos National Laboratory; Lim, Hyunkyung [STONY BROOK UNIV; Yu, Yan [STONY BROOK UNIV; Glimm, James G [STONY BROOK UNIV

    2009-01-01

    We propose mathematical, physical and numerical principles which are important for the modeling of turbulent mixing, especially the classical and well studied Rayleigh-Taylor and Richtmyer-Meshkov instabilities which involve acceleration driven mixing of a fluid discontinuity layer, by a steady accerleration or an impulsive force.

  1. Modeling and Numerical Simulation of Bioheat Transfer and Biomechanics in Soft Tissue

    E-Print Network [OSTI]

    Zhang, Jun

    Modeling and Numerical Simulation of Bioheat Transfer and Biomechanics in Soft Tissue #3; Wensheng techniques are eÆcient. Key words: Bioheat transfer, biomechanics, discretization, iterative solver. 1 do in engineering area by solving constitutive equations. One of the major diÆculties in biomechanics

  2. NUMERICAL MODELLING OF THE DEEP IMPACT MISSION EXPERIMENT K. Wnnemann1 , and H. J. Melosh1

    E-Print Network [OSTI]

    Collins, Gareth

    NUMERICAL MODELLING OF THE DEEP IMPACT MISSION EXPERIMENT K. Wünnemann1 , G. S. Collins2 , and H. J@lpl.arizona.edu, 2 Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK, g.collins@imperial.ac.uk . Introduction: NASA's Deep Impact Mission (launched January 2005) will provide, for the first time ever

  3. Numerical Simulation of the December 26, 2004 Indian Ocean Tsunami using a Boussinesq model

    E-Print Network [OSTI]

    Kirby, James T.

    tsunami education or tsunami warning system in the re- gion exaccerbated the number of fatalities, even. Scientists had been warning of the growing exposure of coastal residents to tsunami hazards for yearsNumerical Simulation of the December 26, 2004 Indian Ocean Tsunami using a Boussinesq model Philip

  4. September 25, 2006 Numerical modeling of the effect of carbon dioxide

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    September 25, 2006 Numerical modeling of the effect of carbon dioxide sequestration on the rate souterrain de dioxyde de carbone sur la déformation des calcaires par dissolution sous contrainte: résultats@obs.ujf- grenoble.fr, marielle.collombet@ujf-grenoble.fr, yleguen@lgit.obs.ujf-grenoble.fr. #12;Abstract When carbon

  5. LABORATORY-NUMERICAL MODEL COMPARISONS OF CANYON FLOWS: A PARAMETER STUDY.

    E-Print Network [OSTI]

    LABORATORY-NUMERICAL MODEL COMPARISONS OF CANYON FLOWS: A PARAMETER STUDY. DON L. BOYER Cite Scientifique ­ 59655 - Villeneuve d'Ascq cedex (France) ABSTRACT An integrated set of laboratory surrounding a coastal canyon and, further, to explore the degree to which laboratory experiments can provide

  6. CONCEPTUAL AND NUMERICAL MODELS OF OXYGEN DIFFUSION, SULPHIDE OXIDATION AND ACID MINE DRAINAGE WITHIN

    E-Print Network [OSTI]

    Aubertin, Michel

    CONCEPTUAL AND NUMERICAL MODELS OF OXYGEN DIFFUSION, SULPHIDE OXIDATION AND ACID MINE DRAINAGE The generation and transport of acid mine drainage (AMD) through discretely fractured porous media is simulated. RÉSUMÉ La génération et le transport des produits issus du drainage minier acide (DMA) dans un milieu

  7. January 2, 2008 Numerical modeling of the effect of carbon dioxide

    E-Print Network [OSTI]

    Boyer, Edmond

    January 2, 2008 Numerical modeling of the effect of carbon dioxide sequestration on the rate souterrain de dioxyde de carbone sur la déformation des calcaires par dissolution sous contrainte: résultats;Abstract When carbon dioxide (CO2) is injected into an aquifer or a depleted geological reservoir, its

  8. Numerical modelling of the blowing phase in the production of glass containers

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Numerical modelling of the blowing phase in the production of glass containers W. Dijkstraa , R to simulate the blowing of glass containers that are not rotationally symmetric. The contact between glass illustrates the results. Keywords: Boundary element method, blowing phase, glass, Stokes equations 1

  9. MODELING AND ADAPTIVE NUMERICAL TECHNIQUES FOR OXI-DATION OF CERAMIC COMPOSITES

    E-Print Network [OSTI]

    Adjerid, Slimane

    . INTRODUCTION Oxidation shortens the life of ceramic matrix composites by, e.g., chang- ing the elasticMODELING AND ADAPTIVE NUMERICAL TECHNIQUES FOR OXI- DATION OF CERAMIC COMPOSITES S. Adjerid, M. Ai reaction 1-3 . Composite materials are protected by coatings; however, cracks that form as a result

  10. NUMERICAL MODELLING OF AUTOGENOUS HEALING AND RECOVERY OF MECHANICAL PROPERTIES IN ULTRA-HIGH

    E-Print Network [OSTI]

    Boyer, Edmond

    in the cementitious matrix can react with carbon dioxide dissolved in the water filling the crack. Autogenous healingNUMERICAL MODELLING OF AUTOGENOUS HEALING AND RECOVERY OF MECHANICAL PROPERTIES IN ULTRA into the crack and leads to a partial recovery of mechanical properties (Young's modulus, tensile strength

  11. Numerical Passage from Radiative Heat Transfer to Nonlinear Diffusion Models \\Lambda

    E-Print Network [OSTI]

    Schmeiser, Christian

    Numerical Passage from Radiative Heat Transfer to Nonlinear Diffusion Models \\Lambda A. Klar y C. Schmeiser z Abstract Radiative heat transfer equations including heat conduction are consid­ ered situations are presented. Keywords. radiative heat transfer, asymptotic analysis, nonlinear diffusion limit

  12. LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY CONVERTERS

    E-Print Network [OSTI]

    Haller, Merrick

    1 LABORATORY OBSERVATIONS AND NUMERICAL MODELING OF THE EFFECTS OF AN ARRAY OF WAVE ENERGY of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments absorption is a reasonable predictor of the effect of WECs on the far field. Keywords: wave- energy; spectral

  13. Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2

    E-Print Network [OSTI]

    Kirby, James T.

    Numerical Modeling of Hydro-acoustic Waves In Weakly Compressible Fluid Ali Abdolali1,2 , James T of Civil Engineering, University of Roma Tre Low-frequency hydro-acoustic waves are precursors of tsunamis. Detection of hydro-acoustic waves generated due to the water column compression triggered by sudden seabed

  14. Numerical simulation of breaking waves by a multi-scale turbulence model

    E-Print Network [OSTI]

    Zhao, Qun

    and diffusion are of the same order at the trough level. Above the trough level, turbulent convection dominates-dimensional MAC type finite difference method. The third-order upwind scheme proposed by Kawamura and KawaharaNumerical simulation of breaking waves by a multi-scale turbulence model Qun Zhaoa,*, Steve

  15. On the application of robust numerical methods to a complete-flow wave-current model

    E-Print Network [OSTI]

    Madden, Niall

    -current interaction in the presence of weakly turbulent flow leading to an Orr-Sommerfeld type problem, and a system of two singularly perturbed reaction-diffusion equations from a k- turbulence model. The numerical of modifying the scheme to stabilize it, a mesh tailored to the specific problem is used. In this study we

  16. On the application of robust numerical methods to a complete-flow wave-current model

    E-Print Network [OSTI]

    Madden, Niall

    -current interaction in the presence of weakly turbulent flow leading to an Orr-Sommerfeld type problem and a system of two singularly perturbed reaction-diffusion equations from a k- turbulence model. The numerical layers. Instead of modifying the scheme to stabilize it, a mesh tailored to the specific problem is used

  17. On the seismic response of deep-seated rock slope instabilities --Insights from numerical modeling

    E-Print Network [OSTI]

    On the seismic response of deep-seated rock slope instabilities -- Insights from numerical modeling 2015 Accepted 3 April 2015 Available online 15 April 2015 Keywords: Seismic landslide hazard Spectral component of seismic hazard in mountainous regions. While many seismic slope stability analysis methods

  18. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis

  19. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial with heat transfer along the stator, which corresponds to the experiment of Djaoui et al. [2]. Our results

  20. Precipitation sensitivity to autoconversion rate in a Numerical Weather Prediction model

    E-Print Network [OSTI]

    Marsham, John

    1 Precipitation sensitivity to autoconversion rate in a Numerical Weather Prediction model Céline;2 Summary Aerosols are known to significantly affect cloud and precipitation patterns and intensity. The impact of changing cloud droplet number concentration (CDNC), on cloud and precipitation evolution can

  1. Numerical investigation of high-pressure combustion in rocket engines using Flamelet/Progress-variable models

    E-Print Network [OSTI]

    Coclite, A; De Palma, P; Pascazio, G

    2015-01-01

    The present paper deals with the numerical study of high pressure LOx/H2 or LOx/hydrocarbon combustion for propulsion systems. The present research effort is driven by the continued interest in achieving low cost, reliable access to space and more recently, by the renewed interest in hypersonic transportation systems capable of reducing time-to-destination. Moreover, combustion at high pressure has been assumed as a key issue to achieve better propulsive performance and lower environmental impact, as long as the replacement of hydrogen with a hydrocarbon, to reduce the costs related to ground operations and increase flexibility. The current work provides a model for the numerical simulation of high- pressure turbulent combustion employing detailed chemistry description, embedded in a RANS equations solver with a Low Reynolds number k-omega turbulence model. The model used to study such a combustion phenomenon is an extension of the standard flamelet-progress-variable (FPV) turbulent combustion model combined ...

  2. Modelling and Numerical Simulation of Gas Migration in a Nuclear Waste Repository

    E-Print Network [OSTI]

    Bourgeat, Alain; Smai, Farid

    2010-01-01

    We present a compositional compressible two-phase, liquid and gas, flow model for numerical simulations of hydrogen migration in deep geological radioactive waste repository. This model includes capillary effects and the gas diffusivity. The choice of the main variables in this model, Total or Dissolved Hydrogen Mass Concentration and Liquid Pressure, leads to a unique and consistent formulation of the gas phase appearance and disappearance. After introducing this model, we show computational evidences of its adequacy to simulate gas phase appearance and disappearance in different situations typical of underground radioactive waste repository.

  3. A numerical model for the gamma-ray emission of the microquasar LS 5039

    E-Print Network [OSTI]

    V. Bosch-Ramon; J. M. Paredes

    2004-07-01

    The possible association between the microquasar LS 5039 and the EGRET source 3EG J1824-1514 suggests that microquasars could also be sources of high energy gamma-rays. In this paper, we explore, with a detailed numerical model, if this system can produce the emission detected by EGRET (>100 MeV) through inverse Compton (IC) scattering. Our numerical approach considers a population of relativistic electrons entrained in a cylindrical inhomogeneous jet, interacting with both the radiation and the magnetic fields, taking into account the Thomson and Klein-Nishina regimes of interaction. The computed spectrum reproduces the observed spectral characteristics at very high energy.

  4. Validation of New Process Models for Large Injection-Molded Long-Fiber Thermoplastic Composite Structures

    SciTech Connect (OSTI)

    Nguyen, Ba Nghiep; Jin, Xiaoshi; Wang, Jin; Kunc, Vlastimil; Tucker III, Charles L.

    2012-02-23

    This report describes the work conducted under the CRADA Nr. PNNL/304 between Battelle PNNL and Autodesk whose objective is to validate the new process models developed under the previous CRADA for large injection-molded LFT composite structures. To this end, the ARD-RSC and fiber length attrition models implemented in the 2013 research version of Moldflow was used to simulate the injection molding of 600-mm x 600-mm x 3-mm plaques from 40% glass/polypropylene (Dow Chemical DLGF9411.00) and 40% glass/polyamide 6,6 (DuPont Zytel 75LG40HSL BK031) materials. The injection molding was performed by Injection Technologies, Inc. at Windsor, Ontario (under a subcontract by Oak Ridge National Laboratory, ORNL) using the mold offered by the Automotive Composite Consortium (ACC). Two fill speeds under the same back pressure were used to produce plaques under slow-fill and fast-fill conditions. Also, two gating options were used to achieve the following desired flow patterns: flows in edge-gated plaques and in center-gated plaques. After molding, ORNL performed measurements of fiber orientation and length distributions for process model validations. The structure of this report is as follows. After the Introduction (Section 1), Section 2 provides a summary of the ARD-RSC and fiber length attrition models. A summary of model implementations in the latest research version of Moldflow is given in Section 3. Section 4 provides the key processing conditions and parameters for molding of the ACC plaques. The validations of the ARD-RSC and fiber length attrition models are presented and discussed in Section 5. The conclusions will be drawn in Section 6.

  5. Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study

    SciTech Connect (OSTI)

    Anh Bui; Nam Dinh; Brian Williams

    2013-09-01

    In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy’s Consortium for Advanced Simulation of LWRs program’s VUQ Focus Area.

  6. Experimental Validation of Stochastic Wireless Urban Channel Model: Estimation and Prediction

    SciTech Connect (OSTI)

    Kuruganti, Phani Teja [ORNL] [ORNL; Ma, Xiao [ORNL] [ORNL; Djouadi, Seddik M [ORNL] [ORNL

    2012-01-01

    Stochastic differential equations (SDE) can be used to describe the time-varying nature of wireless channels. This paper validates a long-term fading channel model for estimation and prediction from solely using measured received signal strength measurements. Such channel models can be used for optimizing wireless networks deployed for industrial automation, public access, and communication. This paper uses two different sets of received signal measurement data to estimate an predict the signal strength based on past measurements. The realworld performance of the estimation and prediction algorithm is demonstrated.

  7. Validation of detailed thermal hydraulic models used for LMR safety and for improvement of technical specifications

    SciTech Connect (OSTI)

    Dunn, F.E.

    1995-12-31

    Detailed steady-state and transient coolant temperatures and flow rates from an operating reactor have been used to validate the multiple pin model in the SASSYS-1 liquid metal reactor systems analysis code. This multiple pin capability can be used for explicit calculations of axial and lateral temperature distributions within individual subassemblies. Thermocouples at a number of axial locations and in a number of different coolant sub-channels m the XXO9 instrumented subassembly in the EBR-II reactor provided temperature data from the Shutdown Heat Removal Test (SHRT) series. Flow meter data for XXO9 and for the overall system are also available from these tests. Results of consistent SASSYS-1 multiple pin analyses for both the SHRT-45 loss-of-flow-without-scram-test and the S14RT-17 protected loss-of-flow test agree well with the experimental data, providing validation of the SASSYS-1 code over a wide range of conditions.

  8. Flow in internet shopping: a validity study and an examination of a model specifying antecedents and consequences of flow 

    E-Print Network [OSTI]

    Guo, Yi

    2005-02-17

    fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2004 Major Subject: Information and Operations Management FLOW IN INTERNET SHOPPING: A VALIDITY STUDY AND AN EXAMINATION OF A MODEL SPECIFYING...) ____________________________ ____________________________ Manjit Yadav Dean Wichern (Member) (Head of Department) December 2004 Major Subject: Information and Operations Management iii ABSTRACT Flow in Internet Shopping: A Validity Study and an Examination of a...

  9. Numerical upscaling for the eddy-current model with stochastic magnetic materials

    SciTech Connect (OSTI)

    Eberhard, Jens P. [Computer Simulation Technology, Bad Nauheimer Strasse, 19, D-64289 Darmstadt (Germany)], E-mail: jens.eberhard@cst.com; Popovic, Dan [Simulation in Technology, University of Heidelberg, Im Neuenheimer Feld 368, D-69120 Heidelberg (Germany)], E-mail: dan.popovic@stud.uni-heidelberg.de; Wittum, Gabriel [Simulation in Technology, University of Heidelberg, Im Neuenheimer Feld 368, D-69120 Heidelberg (Germany)], E-mail: wittum@uni-hd.de

    2008-04-01

    This paper deals with the upscaling of the time-harmonic Maxwell equations for heterogeneous media. We analyze the eddy-current approximation of Maxwell's equations to describe the electric field for heterogeneous, isotropic magnetic materials. The magnetic permeability of the materials is assumed to have random heterogeneities described by a Gaussian random field. We apply the so-called Coarse Graining method to develop a numerical upscaling of the eddy-current model. The upscaling uses filtering and averaging procedures in Fourier space which results in a formulation of the eddy-current model on coarser resolution scales where the influence of sub-scale fluctuations is modeled by effective scale- and space-dependent reluctivity tensors. The effective reluctivity tensors can be obtained by solving local partial differential equations which contain a Laplacian as well as a curl-curl operator. We present a computational method how the equation of the combined operators can be discretized and solved numerically using an extended variational formulation compared to standard discretizations. We compare the results of the numerical upscaling of the eddy-current model with theoretical results of Eberhard [J.P. Eberhard, Upscaling for the time-harmonic Maxwell equations with heterogeneous magnetic materials, Physical Review E 72 (3), (2005)] and obtain a very good agreement.

  10. Low frequency eddy current finite element model validation and benchmark studies

    SciTech Connect (OSTI)

    Cherry, M.; Knopp, J. [Materials and Manufacturing Directorate, Air Force Research Laboratory (United States); Mooers, R.; Boehnlein, T. [University of Dayton Research Institute, Dayton, OH (United States); Aldrin, J. C. [Computational Tools, Gurnee, IL (United States); Sabbagh, H. A. [Victor Technologies, LLC, Bloomington, IN (United States)

    2011-06-23

    A finite element method (FEM) model was created to calculate the change in impedance of a coil due to the presence of a notch in a plate. The rectangular notches were created via electrical discharge machining (EDM) in a thick aluminum plate and were positioned at normal and oblique angles (10, 20, and 30 degrees) with respect to the vertical axis of the coil. The FEM method was chosen for this model due to its ability to solve problems in complicated geometries with the use of irregular mesh elements to discretize the solution domain. The change in impedance was calculated from the field variables in the simulation for each probe position along the parallel axis of the plate. The error between the model and the experimental data was approximately 5% for the majority of cases. The validated model was used to investigate more complex problems.

  11. Preliminary characterization of materials for a reactive transport model validation experiment

    SciTech Connect (OSTI)

    Siegel, M.D.; Ward, D.B.; Cheng, W.C.; Bryant, C.; Chocas, C.S.; Reynolds, C.G.

    1993-03-01

    The geochemical properties of a porous sand and several tracers (Ni, Br, and Li) have been characterized for use in a caisson experiment designed to validate sorption models used in models of inactive transport. The surfaces of the sand grains have been examined by a combination of techniques including potentiometric titration, acid leaching, optical microscopy, and scanning electron microscopy with energy-dispersive spectroscopy. The surface studies indicate the presence of small amounts of carbonate, kaolinite and iron-oxyhydroxides. Adsorption of nickel, lithium and bromide by the sand was measured using batch techniques. Bromide was not sorbed by the sand. A linear (K{sub d}) or an isotherm sorption model may adequately describe transport of Li; however, a model describing the changes of pH and the concentrations of other solution species as a function of time and position within the caisson and the concomitant effects on Ni sorption may be required for accurate predictions of nickel transport.

  12. Importance of Second-Order Difference-Frequency Wave-Diffraction Forces in the Validation of a Fast Semi-Submersible Floating Wind Turbine Model: Preprint

    SciTech Connect (OSTI)

    Couling, A. J.; Goupee, A. J.; Robertson, A. N.; Jonkman, J. M.

    2013-06-01

    To better access the abundant offshore wind resource, efforts across the world are being undertaken to develop and improve floating offshore wind turbine technologies. A critical aspect of creating reliable, mature floating wind turbine technology is the development, verification, and validation of efficient computer-aided-engineering (CAE) tools that can be relied upon in the design process. The National Renewable Energy Laboratory (NREL) has created a comprehensive, coupled analysis CAE tool for floating wind turbines, FAST, which has been verified and utilized in numerous floating wind turbine studies. Several efforts are currently underway that leverage the extensive 1/50th-scale DeepCwind wind/wave basin model test dataset, obtained at the Maritime Research Institute Netherlands (MARIN) in 2011, to validate the floating platform functionality of FAST to complement its already validated aerodynamic and structural simulation capabilities. In this paper, further work is undertaken to continue this validation. In particular, the ability of FAST to replicate global response behaviors associated with dynamic wind forces, second-order difference-frequency wave-diffraction forces and their interaction with one another are investigated.

  13. Numerical study of a slip-link model for polymer melts and nanocomposites

    E-Print Network [OSTI]

    Diego Delbiondo; Elian Masnada; Samy Merabia; Marc Couty; Jean-Louis Barrat

    2013-06-10

    We present a numerical study of the slip link model introduced by Likhtman for describing the dy- namics of dense polymer melts. After reviewing the technical aspects associated with the implemen- tation of the model, we extend previous work in several directions. The dependence of the relaxation modulus with the slip link density and the slip link stiffness is reported. Then the nonlinear rheolog- ical properties of the model, for a particular set of parameters, are explored. Finally, we introduce excluded volume interactions in a mean field such as manner in order to describe inhomogeneous systems, and we apply this description to a simple nanocomposite model. With this extension, the slip link model appears as a simple and generic model of a polymer melt, that can be used as an alternative to molecular dynamics for coarse grained simulations of complex polymeric systems.

  14. 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

  15. R&D for computational cognitive and social models : foundations for model evaluation through verification and validation (final LDRD report).

    SciTech Connect (OSTI)

    Slepoy, Alexander; Mitchell, Scott A.; Backus, George A.; McNamara, Laura A.; Trucano, Timothy Guy

    2008-09-01

    Sandia National Laboratories is investing in projects that aim to develop computational modeling and simulation applications that explore human cognitive and social phenomena. While some of these modeling and simulation projects are explicitly research oriented, others are intended to support or provide insight for people involved in high consequence decision-making. This raises the issue of how to evaluate computational modeling and simulation applications in both research and applied settings where human behavior is the focus of the model: when is a simulation 'good enough' for the goals its designers want to achieve? In this report, we discuss two years' worth of review and assessment of the ASC program's approach to computational model verification and validation, uncertainty quantification, and decision making. We present a framework that extends the principles of the ASC approach into the area of computational social and cognitive modeling and simulation. In doing so, we argue that the potential for evaluation is a function of how the modeling and simulation software will be used in a particular setting. In making this argument, we move from strict, engineering and physics oriented approaches to V&V to a broader project of model evaluation, which asserts that the systematic, rigorous, and transparent accumulation of evidence about a model's performance under conditions of uncertainty is a reasonable and necessary goal for model evaluation, regardless of discipline. How to achieve the accumulation of evidence in areas outside physics and engineering is a significant research challenge, but one that requires addressing as modeling and simulation tools move out of research laboratories and into the hands of decision makers. This report provides an assessment of our thinking on ASC Verification and Validation, and argues for further extending V&V research in the physical and engineering sciences toward a broader program of model evaluation in situations of high consequence decision-making.

  16. Numerical-Model Investigation of the Hydrothermal Regime of a Straight-Through Shallow Cooling Pond

    SciTech Connect (OSTI)

    Sokolov, A. S. [JSC 'VNIIG im. B. E. Vedeneeva' (Russian Federation)] [JSC 'VNIIG im. B. E. Vedeneeva' (Russian Federation)

    2013-11-15

    A mathematic model based on solution of hydrodynamics and heat-transfer equations by the finite-element method is constructed to predict the hydrothermal regime of a straight-through shallow cooling pond, which provides cooling circulating water to a repository of spent nuclear fuel. Numerical experiments made it possible to evaluate the influence exerted by wind conditions and flow rate of water in the river on the temperature of the circulating water.

  17. Value of Laboratory Experiments for Code Validations

    SciTech Connect (OSTI)

    Wawersik, W.R.

    1998-12-14

    Numerical codes have become indispensable for designing underground structures and interpretating the behavior of geologic systems. Because of the complexities of geologic systems, however, code calculations often are associated with large quantitative uncertainties. This papers presents three examples to demonstrate the value of laboratory(or bench scale) experiments to evaluate the predictive capabilities of such codes with five major conclusions: Laboratory or bench-scale experiments are a very cost-effective, controlled means of evaluating and validating numerical codes, not instead of but before or at least concurrent with the implementation of in situ studies. The design of good laboratory validation tests must identifj what aspects of a code are to be scrutinized in order to optimize the size, geometry, boundary conditions, and duration of the experiments. The design of good and sometimes difficult numerical analyses and sensitivity studies. Laboratory validation tests must involve: Good validation experiments will generate independent data sets to identify the combined effect of constitutive models, model generalizations, material parameters, and numerical algorithms. Successfid validations of numerical codes mandate a close collaboration between experimentalists and analysts drawing from the full gamut of observations, measurements, and mathematical results.

  18. Numerical modeling of hydraulic fracture problem in permeable medium using cohesive zone model

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    or radioactive waste [30], geothermal Corresponding author Email address: benoit.carrier@enpc.fr (Benoit Carrier processes. During the last sixty years, numerous papers [3, 7, 14, 21, 35, 34, 41, 25, 27, 22, 38, 36, 1. In the recent years, a scaling and asymptotic framework was built to determine the influence of the physical

  19. Experiments to populate and validate a processing model for polyurethane foam :

    SciTech Connect (OSTI)

    Mondy, Lisa Ann; Rao, Rekha Ranjana; Shelden, Bion; Soehnel, Melissa Marie; O'Hern, Timothy J.; Grillet, Anne; Celina, Mathias Christopher; Wyatt, Nicholas B.; Russick, Edward Mark; Bauer, Stephen J.; Hileman, Michael Bryan; Urquhart, Alexander; Thompson, Kyle Richard; Smith, David Michael

    2014-03-01

    We are developing computational models to elucidate the expansion and dynamic filling process of a polyurethane foam, PMDI. The polyurethane of interest is chemically blown, where carbon dioxide is produced via the reaction of water, the blowing agent, and isocyanate. The isocyanate also reacts with polyol in a competing reaction, which produces the polymer. Here we detail the experiments needed to populate a processing model and provide parameters for the model based on these experiments. The model entails solving the conservation equations, including the equations of motion, an energy balance, and two rate equations for the polymerization and foaming reactions, following a simplified mathematical formalism that decouples these two reactions. Parameters for the polymerization kinetics model are reported based on infrared spectrophotometry. Parameters describing the gas generating reaction are reported based on measurements of volume, temperature and pressure evolution with time. A foam rheology model is proposed and parameters determined through steady-shear and oscillatory tests. Heat of reaction and heat capacity are determined through differential scanning calorimetry. Thermal conductivity of the foam as a function of density is measured using a transient method based on the theory of the transient plane source technique. Finally, density variations of the resulting solid foam in several simple geometries are directly measured by sectioning and sampling mass, as well as through x-ray computed tomography. These density measurements will be useful for model validation once the complete model is implemented in an engineering code.

  20. Evaluating Domestic Hot Water Distribution System Options with Validated Analysis Models

    SciTech Connect (OSTI)

    Weitzel, E.; Hoeschele, E.

    2014-09-01

    A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. Transient System Simulation Tool (TRNSYS) is a full distribution system developed that has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. In this study, the Building America team built upon previous analysis modeling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall, 124 different TRNSYS models were simulated. The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

  1. Dynamic Model Validation of PV Inverters Under Short-Circuit Conditions: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Singh, M.; Bravo, R.; Gevorgian, V.

    2013-03-01

    Photovoltaic (PV) modules have dramatically decreased in price in the past few years, spurring the expansion of photovoltaic deployment. Residential and commercial rooftop installations are connected to the distribution network; large-scale installation PV power plants (PVPs) have benefited from tax incentives and the low cost of PV modules. As the level penetration of PV generation increases, the impact on power system reliability will also be greater. Utility power system planners must consider the role of PV generation in power systems more realistically by representing PV generation in dynamic stability analyses. Dynamic models of PV inverters have been developed in the positive sequence representation. NREL has developed a PV inverter dynamic model in PSCAD/EMTDC. This paper validates the dynamic model with an actual hardware bench test conducted by Southern California Edison's Distributed Energy Resources laboratory. All the fault combinations -- symmetrical and unsymmetrical -- were performed in the laboratory. We compare the simulation results with the bench test results.

  2. Assessment of the Value, Impact, and Validity of the Jobs and Economic Development Impacts (JEDI) Suite of Models

    SciTech Connect (OSTI)

    Billman, L.; Keyser, D.

    2013-08-01

    The Jobs and Economic Development Impacts (JEDI) models, developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), use input-output methodology to estimate gross (not net) jobs and economic impacts of building and operating selected types of renewable electricity generation and fuel plants. This analysis provides the DOE with an assessment of the value, impact, and validity of the JEDI suite of models. While the models produce estimates of jobs, earnings, and economic output, this analysis focuses only on jobs estimates. This validation report includes an introduction to JEDI models, an analysis of the value and impact of the JEDI models, and an analysis of the validity of job estimates generated by JEDI model through comparison to other modeled estimates and comparison to empirical, observed jobs data as reported or estimated for a commercial project, a state, or a region.

  3. Validation of the Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidating extendedArchived CERES Surface

  4. Validation of the RRTM Shortwave Radiation Model and Comparison to GCM Shortwave Models

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidating extendedArchived CERES

  5. A Numerical Model of the Temperature Field of the Cast and Solidified Ceramic Material

    SciTech Connect (OSTI)

    Kavicka, Frantisek; Sekanina, Bohumil; Stransky, Karel; Stetina, Josef [Brno University of Technology, Brno, Technicka 2 (Czech Republic); Dobrovska, Jana [Technical University of Ostrava, Ostrava, Tr. 17.listopadu 17 (Czech Republic)

    2010-06-15

    Corundo-baddeleyit material (CBM)--EUCOR--is a heat- and wear-resistant material even at extreme temperatures. This article introduces a numerical model of solidification and cooling of this material in a non-metallic mould. The model is capable of determining the total solidification time of the casting and also the place of the casting which solidifies last. Furthermore, it is possible to calculate the temperature gradient in any point and time, and also determine the local solidification time and the solidification interval of any point. The local solidification time is one of the input parameters for the cooperating model of chemical heterogeneity. This second model and its application on samples of EUCOR prove that the applied method of measurement of chemical heterogeneity provides detailed quantitative information on the material structure and makes it possible to analyse the solidification process. The analysis of this process entails statistical processing of the results of the measurements of the heterogeneity of the components of EUCOR and performs correlation of individual components during solidification. The crystallisation process seems to be very complicated, where the macro- and microscopic segregations differ significantly. The verification of both numerical models was conducted on a real cast 350x200x400 mm block.

  6. Experimental validation of a kilovoltage x-ray source model for computing imaging dose

    SciTech Connect (OSTI)

    Poirier, Yannick, E-mail: yannick.poirier@cancercare.mb.ca [CancerCare Manitoba, 675 McDermot Ave, Winnipeg, Manitoba R3E 0V9 (Canada)] [CancerCare Manitoba, 675 McDermot Ave, Winnipeg, Manitoba R3E 0V9 (Canada); Kouznetsov, Alexei; Koger, Brandon [Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)] [Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Tambasco, Mauro, E-mail: mtambasco@mail.sdsu.edu [Department of Physics, San Diego State University, San Diego, California 92182-1233 and Department of Physics and Astronomy and Department of Oncology, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)] [Department of Physics, San Diego State University, San Diego, California 92182-1233 and Department of Physics and Astronomy and Department of Oncology, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

    2014-04-15

    Purpose: To introduce and validate a kilovoltage (kV) x-ray source model and characterization method to compute absorbed dose accrued from kV x-rays. Methods: The authors propose a simplified virtual point source model and characterization method for a kV x-ray source. The source is modeled by: (1) characterizing the spatial spectral and fluence distributions of the photons at a plane at the isocenter, and (2) creating a virtual point source from which photons are generated to yield the derived spatial spectral and fluence distribution at isocenter of an imaging system. The spatial photon distribution is determined by in-air relative dose measurements along the transverse (x) and radial (y) directions. The spectrum is characterized using transverse axis half-value layer measurements and the nominal peak potential (kVp). This source modeling approach is used to characterize a Varian{sup ®} on-board-imager (OBI{sup ®}) for four default cone-beam CT beam qualities: beams using a half bowtie filter (HBT) with 110 and 125 kVp, and a full bowtie filter (FBT) with 100 and 125 kVp. The source model and characterization method was validated by comparing dose computed by the authors’ inhouse software (kVDoseCalc) to relative dose measurements in a homogeneous and a heterogeneous block phantom comprised of tissue, bone, and lung-equivalent materials. Results: The characterized beam qualities and spatial photon distributions are comparable to reported values in the literature. Agreement between computed and measured percent depth-dose curves is ?2% in the homogeneous block phantom and ?2.5% in the heterogeneous block phantom. Transverse axis profiles taken at depths of 2 and 6 cm in the homogeneous block phantom show an agreement within 4%. All transverse axis dose profiles in water, in bone, and lung-equivalent materials for beams using a HBT, have an agreement within 5%. Measured profiles of FBT beams in bone and lung-equivalent materials were higher than their computed counterparts resulting in an agreement within 2.5%, 5%, and 8% within solid water, bone, and lung, respectively. Conclusions: The proposed virtual point source model and characterization method can be used to compute absorbed dose in both the homogeneous and heterogeneous block phantoms within of 2%–8% of measured values, depending on the phantom and the beam quality. The authors’ results also provide experimental validation for their kV dose computation software, kVDoseCalc.

  7. Numerical modeling of laser tunneling ionization in explicit particle-in-cell codes

    SciTech Connect (OSTI)

    Chen, M.; Cormier-Michel, E.; Geddes, C.G.R.; Bruhwiler, D.L.; Yu, L.L.; Esarey, E.; Schroeder, C.B.; Leemans, W.P.

    2013-03-01

    Methods for the calculation of laser tunneling ionization in explicit particle-in-cell codes used for modeling laser–plasma interactions are compared and validated against theoretical predictions. Improved accuracy is obtained by using the direct current form for the ionization rate. Multi level ionization in a single time step and energy conservation have been considered during the ionization process. The effects of grid resolution and number of macro-particles per cell are examined. Implementation of the ionization algorithm in two different particle-in-cell codes is compared for the case of ionization-based electron injection in a laser–plasma accelerator.

  8. gamma-ray emission from microquasars: a numerical model for LSI+61 303

    E-Print Network [OSTI]

    Valenti Bosch-Ramon; Josep M. Paredes

    2004-07-01

    We explore the possible association between the microquasar LSI+61 303 and the EGRET source 2CG 135+01/3EG J0241$+$6103 by studying, with a detailed numerical model, whether this system can produce the emission and the variability detected by EGRET ($>$100 MeV) through inverse Compton (IC) scattering. Our numerical approach considers a population of relativistic electrons entrained in a cylindrical inhomogeneous jet, interacting with both the radiation and the magnetic fields, taking into account the Thomson and Klein-Nishina regimes of interaction. Our results reproduce the observed spectral characteristics and variability at $\\gamma$-rays, thus strengthening the identification of LSI+61 303 as a high-energy $\\gamma$-ray source.

  9. Geant4 Model Validation of Compton Suppressed System for Process monitoring of Spent Fuel

    SciTech Connect (OSTI)

    Bender, Sarah; Unlu, Kenan; Orton, Christopher R.; Schwantes, Jon M.

    2013-05-01

    Nuclear material accountancy is of continuous concern for the regulatory, safeguards, and verification communities. In particular, spent nuclear fuel reprocessing facilities pose one of the most difficult accountancy challenges: monitoring highly radioactive, fluid sample streams in near real-time. The Multi-Isotope Process monitor will allow for near-real-time indication of process alterations using passive gamma-ray detection coupled with multivariate analysis techniques to guard against potential material diversion or to enhance domestic process monitoring. The Compton continuum from the dominant 661.7 keV 137Cs fission product peak obscures lower energy lines which could be used for spectral and multivariate analysis. Compton suppression may be able to mitigate the challenges posed by the high continuum caused by scattering. A Monte Carlo simulation using the Geant4 toolkit is being developed to predict the expected suppressed spectrum from spent fuel samples to estimate the reduction in the Compton continuum. Despite the lack of timing information between decay events in the particle management of Geant4, encouraging results were recorded utilizing only the information within individual decays without accounting for accidental coincidences. The model has been validated with single and cascade decay emitters in two steps: as an unsuppressed system and with suppression activated. Results of the Geant4 model validation will be presented.

  10. Development and Validation of a Slurry Model for Chemical Hydrogen Storage in Fuel Cell Applications

    SciTech Connect (OSTI)

    Brooks, Kriston P.; Pires, Richard P.; Simmons, Kevin L.

    2014-07-25

    The US Department of Energy's (DOE) Hydrogen Storage Engineering Center of Excellence (HSECoE) is developing models for hydrogen storage systems for fuel cell-based light duty vehicle applications for a variety of promising materials. These transient models simulate the performance of the storage system for comparison to the DOE’s Technical Targets and a set of four drive cycles. The purpose of this research is to describe the models developed for slurry-based chemical hydrogen storage materials. The storage systems of both a representative exothermic system based on ammonia borane and endothermic system based on alane were developed and modeled in Simulink®. Once complete the reactor and radiator components of the model were validated with experimental data. The model was then run using a highway cycle, an aggressive cycle, cold-start cycle and hot drive cycle. The system design was adjusted to meet these drive cycles. A sensitivity analysis was then performed to identify the range of material properties where these DOE targets and drive cycles could be met. Materials with a heat of reaction greater than 11 kJ/mol H2 generated and a slurry hydrogen capacity of greater than 11.4% will meet the on-board efficiency and gravimetric capacity targets, respectively.

  11. Validated Models for Radiation Response and Signal Generation in Scintillators: Final Report

    SciTech Connect (OSTI)

    Kerisit, Sebastien N.; Gao, Fei; Xie, YuLong; Campbell, Luke W.; Van Ginhoven, Renee M.; Wang, Zhiguo; Prange, Micah P.; Wu, Dangxin

    2014-12-01

    This Final Report presents work carried out at Pacific Northwest National Laboratory (PNNL) under the project entitled “Validated Models for Radiation Response and Signal Generation in Scintillators” (Project number: PL10-Scin-theor-PD2Jf) and led by Drs. Fei Gao and Sebastien N. Kerisit. This project was divided into four tasks: 1) Electronic response functions (ab initio data model) 2) Electron-hole yield, variance, and spatial distribution 3) Ab initio calculations of information carrier properties 4) Transport of electron-hole pairs and scintillation efficiency Detailed information on the results obtained in each of the four tasks is provided in this Final Report. Furthermore, published peer-reviewed articles based on the work carried under this project are included in Appendix. This work was supported by the National Nuclear Security Administration, Office of Nuclear Nonproliferation Research and Development (DNN R&D/NA-22), of the U.S. Department of Energy (DOE).

  12. Foundation Heat Exchanger Final Report: Demonstration, Measured Performance, and Validated Model and Design Tool

    SciTech Connect (OSTI)

    Hughes, Patrick [ORNL; Im, Piljae [ORNL

    2012-01-01

    Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX) has been coined to refer exclusively to ground heat exchangers installed in the overcut around the basement walls. The primary technical challenge undertaken by this project was the development and validation of energy performance models and design tools for FHX. In terms of performance modeling and design, ground heat exchangers in other construction excavations (e.g., utility trenches) are no different from conventional HGHX, and models and design tools for HGHX already exist. This project successfully developed and validated energy performance models and design tools so that FHX or hybrid FHX/HGHX systems can be engineered with confidence, enabling this technology to be applied in residential and light commercial buildings. The validated energy performance model also addresses and solves another problem, the longstanding inadequacy in the way ground-building thermal interaction is represented in building energy models, whether or not there is a ground heat exchanger nearby. Two side-by-side, three-level, unoccupied research houses with walkout basements, identical 3,700 ft{sup 2} floor plans, and hybrid FHX/HGHX systems were constructed to provide validation data sets for the energy performance model and design tool. The envelopes of both houses are very energy efficient and airtight, and the HERS ratings of the homes are 44 and 45 respectively. Both houses are mechanically ventilated with energy recovery ventilators, with space conditioning provided by water-to-air heat pumps with 2 ton nominal capacities. Separate water-to-water heat pumps with 1.5 ton nominal capacities were used for water heating. In these unoccupied research houses, human impact on energy use (hot water draw, etc.) is simulated to match the national average. At House 1 the hybrid FHX/HGHX system was installed in 300 linear feet of excavation, and 60% of that was construction excavation (needed to construct the home). At House 2 the hybrid FHX/HGHX system was installed in 360 feet of excavation, 50% of which was construction excavation. There are six pipes in all excavations (three par

  13. Numerical modelling of sandstone uniaxial compression test using a mix-mode cohesive fracture model

    E-Print Network [OSTI]

    Gui, Yilin; Kodikara, Jayantha

    2015-01-01

    A mix-mode cohesive fracture model considering tension, compression and shear material behaviour is presented, which has wide applications to geotechnical problems. The model considers both elastic and inelastic displacements. Inelastic displacement comprises fracture and plastic displacements. The norm of inelastic displacement is used to control the fracture behaviour. Meantime, a failure function describing the fracture strength is proposed. Using the internal programming FISH, the cohesive fracture model is programmed into a hybrid distinct element algorithm as encoded in Universal Distinct Element Code (UDEC). The model is verified through uniaxial tension and direct shear tests. The developed model is then applied to model the behaviour of a uniaxial compression test on Gosford sandstone. The modelling results indicate that the proposed cohesive fracture model is capable of simulating combined failure behaviour applicable to rock.

  14. Validation of the thermospheric vector spherical harmonic (VSH) computer model. Master's thesis

    SciTech Connect (OSTI)

    Davis, J.L.

    1991-01-01

    A semi-empirical computer model of the lower thermosphere has been developed that provides a description of the composition and dynamics of the thermosphere (Killeen et al., 1992). Input variables needed to run the VSH model include time, space and geophysical conditions. One of the output variables the model provides, neutral density, is of particular interest to the U.S. Air Force. Neutral densities vary both as a result of change in solar flux (eg. the solar cycle) and as a result of changes in the magnetosphere (eg. large changes occur in neutral density during geomagnetic storms). Satellites in earth orbit experience aerodynamic drag due to the atmospheric density of the thermosphere. Variability in the neutral density described above affects the drag a satellite experiences and as a result can change the orbital characteristics of the satellite. These changes make it difficult to track the satellite's position. Therefore, it is particularly important to insure that the accuracy of the model's neutral density is optimized for all input parameters. To accomplish this, a validation program was developed to evaluate the strengths and weaknesses of the model's density output by comparing it to SETA-2 (satellite electrostatic accelerometer) total mass density measurements.

  15. The NINJA-2 project: Detecting and characterizing gravitational waveforms modelled using numerical binary black hole simulations

    E-Print Network [OSTI]

    The LIGO Scientific Collaboration; the Virgo Collaboration; the NINJA-2 Collaboration; :; J. Aasi; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; K. Ackley; C. Adams; T. Adams; P. Addesso; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; A. Ain; P. Ajith; A. Alemic; B. Allen; A. Allocca; D. Amariutei; M. Andersen; R. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; M. Barbet; B. C. Barish; D. Barker; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. C. Batch; J. Bauchrowitz; Th. S. Bauer; B. Behnke; M. Bejger; M. G. Beker; C. Belczynski; A. S. Bell; C. Bell; G. Bergmann; D. Bersanetti; A. Bertolini; J. Betzwieser; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; S. Biscans; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; S. Bloemen; M. Blom; O. Bock; T. P. Bodiya; M. Boer; G. Bogaert; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; Sukanta Bose; L. Bosi; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; S. Buchman; T. Bulik; H. J. Bulten; A. Buonanno; R. Burman; D. Buskulic; C. Buy; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavaglià; F. Cavalier; R. Cavalieri; C. Celerier; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. J. Chamberlin; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; C. Collette; M. Colombini; L. Cominsky; M. Constancio Jr.; A. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corpuz; A. Corsi; C. A. Costa; M. W. Coughlin; S. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; R. Coyne; K. Craig; J. D. E. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; G. Debreczeni; J. Degallaix; S. Deléglise; W. Del Pozzo; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. De Rosa; R. T. DeRosa; R. DeSalvo; S. Dhurandhar; M. Díaz; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; A. Donath; F. Donovan; K. L. Dooley; S. Doravari; S. Dossa; R. Douglas; T. P. Downes; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; S. Dwyer; T. Eberle; T. Edo; M. Edwards; A. Effler; H. Eggenstein; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endr?czi; R. Essick; T. Etzel; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. M. Farr; M. Favata; H. Fehrmann; M. M. Fejer; D. Feldbaum; F. Feroz; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; S. Gaonkar; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; S. Ghosh; J. A. Giaime; K. D. Giardina; A. Giazotto; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Gräf; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. Gushwa; E. K. Gustafson; R. Gustafson; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. Hart; M. T. Hartman; C. -J. Haster; K. Haughian; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; S. Hooper; P. Hopkins; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; P. Jaranowski; Y. Ji; F. Jiménez-Forteza; W. W. Johnson; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; J. Karlen; M. Kasprzack; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; F. Kawazoe; F. Kéfélian; G. M. Keiser; D. Keitel; D. B. Kelley; W. Kells; A. Khalaidovski

    2014-01-05

    The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave astrophysics communities. The purpose of NINJA is to study the ability to detect gravitational waves emitted from merging binary black holes and recover their parameters with next-generation gravitational-wave observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete binary black hole hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a "blind injection challenge" similar to that conducted in recent LIGO and Virgo science runs, we added 7 hybrid waveforms to two months of data recolored to predictions of Advanced LIGO and Advanced Virgo sensitivity curves during their first observing runs. The resulting data was analyzed by gravitational-wave detection algorithms and 6 of the waveforms were recovered with false alarm rates smaller than 1 in a thousand years. Parameter estimation algorithms were run on each of these waveforms to explore the ability to constrain the masses, component angular momenta and sky position of these waveforms. We also perform a large-scale monte-carlo study to assess the ability to recover each of the 60 hybrid waveforms with early Advanced LIGO and Advanced Virgo sensitivity curves. Our results predict that early Advanced LIGO and Advanced Virgo will have a volume-weighted average sensitive distance of 300Mpc (1Gpc) for $10M_{\\odot}+10M_{\\odot}$ ($50M_{\\odot}+50M_{\\odot}$) binary black hole coalescences. We demonstrate that neglecting the component angular momenta in the waveform models used in matched-filtering will result in a reduction in sensitivity for systems with large component angular momenta. [Abstract abridged for ArXiv, full version in PDF

  16. Monitoring and Numerical Modeling of Shallow CO{sub 2} Injection, Greene County, Missouri

    SciTech Connect (OSTI)

    Rovey, Charles; Gouzie, Douglas; Biagioni, Richard

    2013-09-30

    The project titled Monitoring and Numerical Modeling of Shallow CO{sub 2} Injection, Greene County, Missouri provided training for three graduate students in areas related to carbon capture and storage. Numerical modeling of CO{sub 2} injection into the St. Francois aquifer at the Southwest Power Plant Site in Greene County, Missouri indicates that up to 4.1 x 10{sup 5} metric tons of CO{sub 2} per year could be injected for 30 years without exceeding a 3 MPa differential injection pressure. The injected CO{sub 2} would remain sequestered below the top of the overlying caprock (St. Francois confining unit) for more than 1000 years. Geochemical modeling indicates that portions of the injected CO{sub 2} will react rapidly with trace minerals in the aquifer to form various solid carbonate mineral phases. These minerals would store significant portions of injected CO{sub 2} over geologic time scales. Finally, a GIS data base on the pore-fluid chemistry of the overlying aquifer system in Missouri, the Ozark aquifer, was compiled from many sources. This data base could become useful in monitoring for leakage from future CO{sub 2} sequestration sites.

  17. A phase screen model for simulating numerically the propagation of a laser beam in rain

    SciTech Connect (OSTI)

    Lukin, I P; Rychkov, D S; Falits, A V [Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk (Russian Federation); Lai, Kin S; Liu, Min R [DSO National Laboratories 20 (Singapore)

    2009-09-30

    The method based on the generalisation of the phase screen method for a continuous random medium is proposed for simulating numerically the propagation of laser radiation in a turbulent atmosphere with precipitation. In the phase screen model for a discrete component of a heterogeneous 'air-rain droplet' medium, the amplitude screen describing the scattering of an optical field by discrete particles of the medium is replaced by an equivalent phase screen with a spectrum of the correlation function of the effective dielectric constant fluctuations that is similar to the spectrum of a discrete scattering component - water droplets in air. The 'turbulent' phase screen is constructed on the basis of the Kolmogorov model, while the 'rain' screen model utiises the exponential distribution of the number of rain drops with respect to their radii as a function of the rain intensity. Theresults of the numerical simulation are compared with the known theoretical estimates for a large-scale discrete scattering medium. (propagation of laser radiation in matter)

  18. Universitt StuttgartInstitut fr Wasserbau, Lehrstuhl fr Hydromechanik und Hydrosystemmodellierung Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    Hydrosystemmodellierung Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations 1/16 Modelling April 2008 Workshop on Numerical Models for Carbon Dioxide Storage in Geological Formations #12 on Numerical Models for Carbon Dioxide Storage in Geological Formations 2/16 CO2 leakage mitigation using

  19. Stochastic models and numerical algorithms for a class of regulatory gene networks

    E-Print Network [OSTI]

    Thomas Fournier; Jean-Pierre Gabriel; Christian Mazza; Jerome Pasquier; Jose Galbete; Nicolas Mermod

    2008-10-01

    Regulatory gene networks contain generic modules like those involving feedback loops, which are essential for the regulation of many biological functions. We consider a class of self-regulated genes which are the building blocks of many regulatory gene networks, and study the steady state distributions of the associated Gillespie algorithm by providing efficient numerical algorithms. We also study a regulatory gene network of interest in synthetic biology and in gene therapy, using mean-field models with time delays. Convergence of the related time-nonhomogeneous Markov chain is established for a class of linear catalytic networks with feedback loops

  20. CFD Model Development and validation for High Temperature Gas Cooled Reactor Cavity Cooling System (RCCS) Applications

    SciTech Connect (OSTI)

    Hassan, Yassin; Corradini, Michael; Tokuhiro, Akira; Wei, Thomas Y.C.

    2014-07-14

    The Reactor Cavity Cooling Systems (RCCS) is a passive safety system that will be incorporated in the VTHR design. The system was designed to remove the heat from the reactor cavity and maintain the temperature of structures and concrete walls under desired limits during normal operation (steady-state) and accident scenarios. A small scale (1:23) water-cooled experimental facility was scaled, designed, and constructed in order to study the complex thermohydraulic phenomena taking place in the RCCS during steady-state and transient conditions. The facility represents a portion of the reactor vessel with nine stainless steel coolant risers and utilizes water as coolant. The facility was equipped with instrumentation to measure temperatures and flow rates and a general verification was completed during the shakedown. A model of the experimental facility was prepared using RELAP5-3D and simulations were performed to validate the scaling procedure. The experimental data produced during the steady-state run were compared with the simulation results obtained using RELAP5-3D. The overall behavior of the facility met the expectations. The facility capabilities were confirmed to be very promising in performing additional experimental tests, including flow visualization, and produce data for code validation.

  1. Numerical modeling of the high-temperature geothermal system of Amatitlan, Guatemala

    SciTech Connect (OSTI)

    Pham, M.; Menzies, A.J.; Sanyal, S.K. [GeothermEx, Inc., Richmond, CA (United States)] [and others

    1996-12-31

    Using the conceptual model of the Amatitlin geothermal system as a guide, a 14 by 10 km numerical model was set up with five layers and a total of 1,220 grid blocks. The number of grid blocks varies from layer to layer, with finer resolution in the two production layers. Boundary blocks for conductive heat transfer, heat and mass recharge, shallow discharge and deep regional fluid flow were added to the model as appropriate. With an inflow of hot fluid (336{degrees}C) at a rate of 450 tones per hour, an inflow of cool fluid (50{degrees}C) at a rate of 620 tons per hour and permeabilities varying from 1.5 to 50 md, the initial state temperatures on all five levels were well matched by the numerical model. The initial state results indicate that highest permeability is present to the southeast of the productive wells, suggesting that considerable additional production potential exists in this area. A two-phase region exists in the upper levels of the reservoir and in the outflow plume; the latter is consistent with the presence of fumaroles along the shoreline of Lago de Amatitlan. To further calibrate the numerical model, enthalpy and pressure data collected during tests of wells AMF-1 and -2 were matched, primarily by varying reservoir storage capacity. Good matches to the observed data were obtained for both wells, although sharp transients could not be matched. Modeling proceeded to the prediction stage under two scenarios: production of 12 and 25 MW (gross) for 30 years. 100% injection of separated water and condensate was assumed to take place in the vicinity of well AMF-3 in both cases. The results show an increase in enthalpy caused by expansion of the two-phase zone during the first year of production, followed by an enthalpy decline as reservoir liquid begins to migrate toward the production area. The two existing production wells (AMF-1 and -2) are predicted to be capable of maintaining output in the 12 MW case throughout the 30-year project life.

  2. Validation of Multiple Tools for Flat Plate Photovoltaic Modeling Against Measured Data

    SciTech Connect (OSTI)

    Freeman, J.; Whitmore, J.; Blair, N.; Dobos, A. P.

    2014-08-01

    This report expands upon a previous work by the same authors, published in the 40th IEEE Photovoltaic Specialists conference. In this validation study, comprehensive analysis is performed on nine photovoltaic systems for which NREL could obtain detailed performance data and specifications, including three utility-scale systems and six commercial scale systems. Multiple photovoltaic performance modeling tools were used to model these nine systems, and the error of each tool was analyzed compared to quality-controlled measured performance data. This study shows that, excluding identified outliers, all tools achieve annual errors within +/-8% and hourly root mean squared errors less than 7% for all systems. It is further shown using SAM that module model and irradiance input choices can change the annual error with respect to measured data by as much as 6.6% for these nine systems, although all combinations examined still fall within an annual error range of +/-8.5%. Additionally, a seasonal variation in monthly error is shown for all tools. Finally, the effects of irradiance data uncertainty and the use of default loss assumptions on annual error are explored, and two approaches to reduce the error inherent in photovoltaic modeling are proposed.

  3. Modeling Framework and Validation of a Smart Grid and Demand Response System for Wind Power Integration

    SciTech Connect (OSTI)

    Broeer, Torsten; Fuller, Jason C.; Tuffner, Francis K.; Chassin, David P.; Djilali, Ned

    2014-01-31

    Electricity generation from wind power and other renewable energy sources is increasing, and their variability introduces new challenges to the power system. The emergence of smart grid technologies in recent years has seen a paradigm shift in redefining the electrical system of the future, in which controlled response of the demand side is used to balance fluctuations and intermittencies from the generation side. This paper presents a modeling framework for an integrated electricity system where loads become an additional resource. The agent-based model represents a smart grid power system integrating generators, transmission, distribution, loads and market. The model incorporates generator and load controllers, allowing suppliers and demanders to bid into a Real-Time Pricing (RTP) electricity market. The modeling framework is applied to represent a physical demonstration project conducted on the Olympic Peninsula, Washington, USA, and validation simulations are performed using actual dynamic data. Wind power is then introduced into the power generation mix illustrating the potential of demand response to mitigate the impact of wind power variability, primarily through thermostatically controlled loads. The results also indicate that effective implementation of Demand Response (DR) to assist integration of variable renewable energy resources requires a diversity of loads to ensure functionality of the overall system.

  4. From deep TLS validation to ensembles of atomic models built from elemental motions

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

    Urzhumtsev, Alexandre; Afonine, Pavel V.; Van Benschoten, Andrew H.; Fraser, James S.; Adams, Paul D.

    2015-07-28

    The translation–libration–screw model first introduced by Cruickshank, Schomaker and Trueblood describes the concerted motions of atomic groups. Using TLS models can improve the agreement between calculated and experimental diffraction data. Because the T, L and S matrices describe a combination of atomic vibrations and librations, TLS models can also potentially shed light on molecular mechanisms involving correlated motions. However, this use of TLS models in mechanistic studies is hampered by the difficulties in translating the results of refinement into molecular movement or a structural ensemble. To convert the matrices into a constituent molecular movement, the matrix elements must satisfy severalmore »conditions. Refining the T, L and S matrix elements as independent parameters without taking these conditions into account may result in matrices that do not represent concerted molecular movements. Here, a mathematical framework and the computational tools to analyze TLS matrices, resulting in either explicit decomposition into descriptions of the underlying motions or a report of broken conditions, are described. The description of valid underlying motions can then be output as a structural ensemble. All methods are implemented as part of the PHENIX project.« less

  5. Numerical modeling of mixed sediment resuspension, transport, and deposition during the March 1998 episodic events in southern Lake

    E-Print Network [OSTI]

    Numerical modeling of mixed sediment resuspension, transport, and deposition during the March 1998 sediment resuspension of mixed (cohesive plus noncohesive) sediment is developed and applied to quantitatively simulate the March 1998 resuspension events in southern Lake Michigan. Some characteristics

  6. Tsunami inundation modeling in constructed environments: A physical and numerical comparison of free-surface elevation, velocity, and momentum flux

    E-Print Network [OSTI]

    Lynett, Patrick

    Tsunami inundation modeling in constructed environments: A physical and numerical comparison April 2013 Available online 17 May 2013 Keywords: Tsunami Inundation Macro-roughness Benchmark COULWAVE Friction factor A laboratory benchmark test for tsunami inundation through an urban waterfront including

  7. Thermodynamic modeling and experimental validation of the Fe-Al-Ni-Cr-Mo alloy system

    SciTech Connect (OSTI)

    Teng, Zhenke; Zhang, F; Miller, Michael K; Liu, Chain T; Huang, Shenyan; Chou, Y.T.; Tien, R; Chang, Y A; Liaw, Peter K

    2012-01-01

    NiAl-type precipitate-strengthened ferritic steels have been known as potential materials for the steam turbine applications. In this study, thermodynamic descriptions of the B2-NiAl type nano-scaled precipitates and body-centered-cubic (BCC) Fe matrix phase for four alloys based on the Fe-Al-Ni-Cr-Mo system were developed as a function of the alloy composition at the aging temperature. The calculated phase structure, composition, and volume fraction were validated by the experimental investigations using synchrotron X-ray diffraction and atom probe tomography. With the ability to accurately predict the key microstructural features related to the mechanical properties in a given alloy system, the established thermodynamic model in the current study may significantly accelerate the alloy design process of the NiAl-strengthened ferritic steels.

  8. A Testing Platform for Validation of Overhead Conductor Aging Models and Understanding Thermal Limits

    SciTech Connect (OSTI)

    Irminger, Philip; Starke, Michael R; Dimitrovski, Aleksandar D; Young II, Marcus Aaron; Rizy, D Tom; Stovall, John P; Overholt, Philip N

    2014-01-01

    Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess the performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.

  9. 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 Bhatnagar–Gross–Krook (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.

  10. Langevin power curve analysis for numerical WEC models with new insights on high frequency power performance

    E-Print Network [OSTI]

    Mücke, Tanja A; Milan, Patrick; Peinke, Joachim

    2015-01-01

    Based on the Langevin equation it has been proposed to obtain power curves for wind turbines from high frequency data of wind speed measurements u(t) and power output P (t). The two parts of the Langevin approach, power curve and drift field, give a comprehensive description of the conversion dynamic over the whole operating range of the wind turbine. The method deals with high frequent data instead of 10 min means. It is therefore possible to gain a reliable power curve already from a small amount of data per wind speed. Furthermore, the method is able to visualize multiple fixed points, which is e.g. characteristic for the transition from partial to full load or in case the conversion process deviates from the standard procedures. In order to gain a deeper knowledge it is essential that the method works not only for measured data but also for numerical wind turbine models and synthetic wind fields. Here, we characterize the dynamics of a detailed numerical wind turbine model and calculate the Langevin power...

  11. Numerical study of a binary Yukawa model in regimes characteristic of globular proteins in solutions

    SciTech Connect (OSTI)

    Giacometti, Achille; Gazzillo, Domenico; Pastore, Giorgio; Das, Tushar Kanti [Istituto Nazionale per la Fisica della Materia and Dipartimento di Chimica Fisica, Universita di Venezia, S. Marta DD 2137, I-30123 Venice (Italy); Dipartimento di Fisica Teorica, Universita di Trieste and INFM-DEMOCRITOS, National Simulation Center, Strada Costiera 11, Miramare, I-34100 Trieste (Italy); ICTP, Diploma Course, Strada Costiera 11, Miramare P.O Box 586, I-34100 Trieste (Italy)

    2005-03-01

    The main goal of this paper is to assess the limits of validity, in the regime of low concentration and strong Coulomb coupling (high molecular charges), of a simple perturbative approximation to the radial distribution functions (RDF's), based upon a low-density expansion of the potential of mean force and proposed to describe protein-protein interactions in a recent small-angle-scattering (SAS) experimental study. A highly simplified Yukawa (screened Coulomb) model of monomers and dimers of a charged globular protein ({beta}-lactoglobulin) in solution is considered. We test the accuracy of the RDF approximation, as a necessary complementary part of the previous experimental investigation, by comparison with the fluid structure predicted by approximate integral equations and exact Monte Carlo (MC) simulations. In the MC calculations, an Ewald construction for Yukawa potentials has been used to take into account the long-range part of the interactions in the weakly screened cases. Our results confirm that the perturbative first-order approximation is valid for this system even at strong Coulomb coupling, provided that the screening is not too weak (i.e., for Debye length smaller than monomer radius). A comparison of the MC results with integral equation calculations shows that both the hypernetted-chain (HNC) and Percus-Yevick closures have a satisfactory behavior under these regimes, with the HNC being superior throughout. The relevance of our findings for interpreting SAS results is also discussed.

  12. Numerical modeling of roll structures in mesoscale vortexes over the Black Sea

    E-Print Network [OSTI]

    Iarova, D A

    2014-01-01

    This paper is a case study of horizontal atmospheric rolls that formed over the Black Sea on 16 August 2007. The rolls were discovered in WRF modeling results for a mesoscale cyclone that originated over the sea on 15 August 2007. The roll formation mechanisms, such as Rayleigh-Benard convective instability, dynamic instability, advection and stretching of vertical velocity field inhomogeneities, are considered. It is shown that indeed convective instability played an important role in the roll formation but dynamic instability did not occur. In order to distinguish other possible mechanisms of the roll formation numerical experiments were performed. In these experiments sea surface temperature in the initial conditions was decreased in order to prevent convective instability. Even though convective instability was suppressed roll-like structures still appeared in the modeling results, although their height and circulation velocity were smaller than in the control run. It was found that these structures were ...

  13. Final Report for "Accurate Numerical Models of the Secondary Electron Yield from Grazing-incidence Collisions".

    SciTech Connect (OSTI)

    Seth A Veitzer

    2008-10-21

    Effects of stray electrons are a main factor limiting performance of many accelerators. Because heavy-ion fusion (HIF) accelerators will operate in regimes of higher current and with walls much closer to the beam than accelerators operating today, stray electrons might have a large, detrimental effect on the performance of an HIF accelerator. A primary source of stray electrons is electrons generated when halo ions strike the beam pipe walls. There is some research on these types of secondary electrons for the HIF community to draw upon, but this work is missing one crucial ingredient: the effect of grazing incidence. The overall goal of this project was to develop the numerical tools necessary to accurately model the effect of grazing incidence on the behavior of halo ions in a HIF accelerator, and further, to provide accurate models of heavy ion stopping powers with applications to ICF, WDM, and HEDP experiments.

  14. Preliminary validation of rock mass models by comparison to laboratory frictional sliding experiments

    SciTech Connect (OSTI)

    Sobolik, S.R.; Miller, J.D.

    1996-09-01

    The U.S. Department of Energy`s (DOE) Yucca Mountain Site Characterization Project (YMP) is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level nuclear waste repository. Site characterization will be facilitated by the construction of an Exploratory Studies Facility (ESF). The ESF and potential repository will be excavated from both nonwelded and welded ashflow tuff with varying rock quality (degree of welding, rock mass strength, etc.) and fault and fracture characteristics. Design concerns for the construction of these facilities include the integrity of the structure during underground testing operations and, if it occurs, the emplacement and storage of high-level nuclear waste which could increase the local temperatures in the underground rock mass to as high as 300{degrees}C. Because of the associated issues regarding personnel and long-term environmental safety, sophisticated jointed rock mass models will be required to provide a high degree of confidence for decisions regarding the design, site characterization, and licensing of such facilities. The objective of the work documented in this report is to perform code validation calculations for three rock-mass computer models. The three rock-mass computer models used for this report are the discrete element code UDEC, Version 1.82; and the finite element continuum joint models JAC2D Version 5.10 and JAS3D Version 1.1. The rock mass behavior predicted by the models are compared to the results of laboratory experiments on layered polycarbonate (Lexan) and granite plate experiments. These experiments examine the rock mass behavior of well-defined jointed rock structures or models of jointed structures under uniaxial and biaxial loading. The laboratory environment allows control over the boundary conditions, material properties, and quality and quantity of the data obtained.

  15. Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models

    SciTech Connect (OSTI)

    Weitzel, E.; Hoeschele, M.

    2014-09-01

    A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

  16. Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM

    E-Print Network [OSTI]

    Robinson, Martin; Ramaioli, Marco

    2013-01-01

    We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...

  17. Two-dimensional numerical model of underground oil-shale retorting

    SciTech Connect (OSTI)

    Travis, B.J.; Hommert, P.J.; Tyner, C.E.

    1983-01-01

    A two-dimensional numerical model of underground oil shale retorting, which fully couples retorting chemistry with fluid and heat flow, has been developed. The model solves the time-dependent, two-dimensional mass, momentum, and energy balance equations for a nine-component fluid (O/sub 2/, N/sub 2/, H/sub 2/, CO/sub 2/, CO, CH/sub 4/, CH/sub x/, H/sub 2/O, and oil). Water and oil can flow in the liquid and/or vapor phases. Retort chemistry includes kerogen pyrolysis, carbonate decomposition, char reactions, and combustion. Also, detailed modeling of heat flow and chemistry inside shale particles allows large rubble sizes as well as small sizes to be considered. The model is compared to one-dimensional experimental data obtained from Lawrence Livermore National Laboratory. The model can be used to examine the effect of two-dimensional variations in shale grade, rubble size, permeability, porosity, geometry, inflow gas composition, etc. on retorting efficiency and process optimization. A sample calculation is presented.

  18. Modeling of a Foamed Emulsion Bioreactor: I. Model Development and Experimental Validation

    E-Print Network [OSTI]

    , a new type of bioreactor for air pollution control referred to as the foamed emulsion bior- eactor (FEBR of an actively growing culture of pollutant-degrading microor- ganisms, made into a foam with the air undergoing. KEYWORDS: VOC control; air pollution control; modeling; biologically activated foam; biodegradation

  19. HOW ACCURATE ARE WEATHER MODELS IN ASSISTING AVALANCHE FORECASTERS? M. Schirmer, B. Jamieson

    E-Print Network [OSTI]

    Jamieson, Bruce

    HOW ACCURATE ARE WEATHER MODELS IN ASSISTING AVALANCHE FORECASTERS? M. Schirmer, B. Jamieson and decision makers strongly rely on Numerical Weather Prediction (NWP) models, for example on the forecasted on forecasted precipitation. KEYWORDS: Numerical weather prediction models, validation, precipitation 1

  20. 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.

  1. The effect of simplifying the building description on the numerical modeling of its thermal performance

    SciTech Connect (OSTI)

    Stetiu, C.

    1993-07-01

    A thermal building simulation program is a numerical model that calculates the response of the building envelopes to weather and human activity, simulates dynamic heating and cooling loads, and heating and cooling distribution systems, and models building equipment operation. The scope of the research is to supply the users of such programs with information about the dangers and benefits of simplifying the input to their models. The Introduction describes the advantages of modeling the heat transfer mechanisms in a building. The programs that perform this type of modeling have, however, limitations. The user is therefore often put in the situation of simplifying the floor plans of the building under study, but not being able to check the effects that this approximation introduces in the results of the simulation. Chapter 1 is a description of methods. It also introduces the floor plans for the office building under study and the ``reasonable`` floor plans simplifications. Chapter 2 presents DOE-2, the thermal building simulation program used in the sensitivity study. The evaluation of the accuracy of the DOE-2 program itself is also presented. Chapter 3 contains the sensitivity study. The complicated nature of the process of interpreting the temperature profile inside a space leads to the necessity of defining different building modes. The study compares the results from the model of the detailed building description with the results from the models of the same building having simplified floor plans. The conclusion is reached that a study of the effects of simplifying the floor plans of a building is important mainly for defining the cases in which this approximation is acceptable. Different results are obtained for different air conditioning/load regimes of the building. 9 refs., 24 figs.

  2. Numerical Modeling of Thermal EOR: Comprehensive Coupling of an AMR-Based Model

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Flow and Geomechanics N. Guy*, G. Enchéry and G. Renard IFP Energies nouvelles, 1-4 avenue de Bois of Thermal EOR: Comprehensive Coupling of an AMR-Based Model of Thermal Fluid Flow and Geomechanics when both thermal fluid flow and geomechanics are coupled in order to take into account variations

  3. 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.

  4. Kinetics Study of Solid Ammonia Borane Hydrogen Release – Modeling and Experimental Validation for Chemical Hydrogen Storage

    SciTech Connect (OSTI)

    Choi, Yong-Joon; Ronnebro, Ewa; Rassat, Scot D.; Karkamkar, Abhijeet J.; Maupin, Gary D.; Holladay, Jamelyn D.; Simmons, Kevin L.; Brooks, Kriston P.

    2014-02-24

    Ammonia borane (AB), NH3BH3, is a promising material for chemical hydrogen storage with 19.6 wt% gravimetric hydrogen capacity of which 16.2 wt% hydrogen can be utilized below 200°C. We have investigated the kinetics of hydrogen release from AB and from an AB-methyl cellulose (AB/MC) composite at temperatures of 160-300°C using both experiments and modeling. The purpose of our study was to show safe hydrogen release without thermal runaway effects and to validate system model kinetics. AB/MC released hydrogen at ~20°C lower than neat AB and at a rate that is two times faster. Based on the experimental results, the kinetics equations were revised to better represent the growth and nucleation process during decomposition of AB. We explored two different reactor concepts; Auger and fixed bed. The current Auger reactor concept turned out to not be appropriate, however, we demonstrated safe self-propagation of the hydrogen release reaction of solid AB/MC in a fixed bed reactor.

  5. Tidal Downsizing model. I. Numerical methods: saving giant planets from tidal disruptions

    E-Print Network [OSTI]

    Nayakshin, Sergei

    2014-01-01

    Tidal Downsizing (TD) is a recently developed planet formation theory that supplements the classical Gravitational disc Instability (GI) model with planet migration inward and tidal disruptions of GI fragments in the inner regions of the disc. Numerical methods for a detailed population synthesis of TD planets are presented here. As an example application, the conditions under which GI fragments collapse faster than they migrate into the inner $a\\sim$ few AU disc are considered. It is found that most gas fragments are tidally or thermally disrupted unless (a) their opacity is $\\sim 3$ orders of magnitude less than the interstellar dust opacity at metallicities typical of the observed giant planets, or (b) the opacity is high but the fragments accrete large dust grains (pebbles) from the disc. Case (a) models produce very low mass solid cores ($M_{\\rm core} < 0.1$ Earth masses) and follow a negative correlation of giant planet frequency with host star metallicity. In contrast, case (b) models produce massiv...

  6. 4.4 DEVELOPING AND VALIDATING A MODEL FOR WAS TE LOAD ALLOCATION by Frank A.P.C. Gobas, John P. Pasternak,

    E-Print Network [OSTI]

    45 4.4 DEVELOPING AND VALIDATING A MODEL FOR WAS TE LOAD ALLOCATION 4.4 by Frank A.P.C. Gobas, John AND FIELD VALIDATION OF A MULTI-MEDIA EXPOSURE ASSESSMENT MODEL FOR WASTE LOAD ALLOCATION IN THE FRASER an important role in environmental management. To be useful for environmental quality management, models should

  7. Numerical modeling of mixed sediment resuspension, transport, and deposition during the March 1998 episodic events in southern Lake

    E-Print Network [OSTI]

    Stroud, Jonathan

    Numerical modeling of mixed sediment resuspension, transport, and deposition during the March 1998 2006; published 17 February 2007. [1] A two-dimensional sediment transport model capable of simulating sediment resuspension of mixed (cohesive plus noncohesive) sediment is developed and applied

  8. Introduction Flattening the Earth Continuation procedure Flat Earth Numerical simulations Continuation from a flat to a round Earth model

    E-Print Network [OSTI]

    Boyer, Edmond

    Introduction Flattening the Earth Continuation procedure Flat Earth Numerical simulations Continuation from a flat to a round Earth model in the coplanar orbit transfer problem M. Cerf1, T. Haberkorn, SADCO 2011, March 2nd M. Cerf, T. Haberkorn, E. Tr´elat Continuation from a flat to a round Earth model

  9. Theoretical Model of ITER High Resolution H-alpha Spectroscopy for a Strong Divertor Stray Light and Validation Against JET-ILW Experiments

    E-Print Network [OSTI]

    Theoretical Model of ITER High Resolution H-alpha Spectroscopy for a Strong Divertor Stray Light and Validation Against JET-ILW Experiments

  10. Central South Pacific thermocline water circulation from a high-resolution ocean model validated against satellite data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Central South Pacific thermocline water circulation from a high-resolution ocean model validated. Introduction [2] Most South Pacific Ocean studies have been focused on its western or eastern part, leaving 12 January 2009; accepted 28 January 2009; published 13 May 2009. [1] The oceanic circulation

  11. Thermal aging modeling and validation on the Mo containing Fe-Cr-Ni alloys

    SciTech Connect (OSTI)

    Yang, Ying; Tan, Lizhen; Busby, Jeremy T.

    2015-04-01

    Thermodynamics of intermetallic phases in Fe-rich Fe-Cr-Ni-Mo alloys is critical knowledge to understand thermal aging effect on the phase stability of Mo-containing austenitic steels, which subsequently facilitates alloy design/improvement and degradation mitigation of these materials for reactor applications. Among the intermetallic phases, Chi (?), Laves, and Sigma (?) are often of concern because of their tendency to cause embrittlement of the materials. The focus of this study is thermal stability of the Chi and Laves phases as they were less studied compared to the Sigma phase. Coupled with thermodynamic modeling, thermal stability of intermetallic phases in Mo containing Fe-Cr-Ni alloys was investigated at 1000, 850 and 700 C for different annealing times. The morphologies, compositions and crystal structures of the precipitates of the intermetallic phases were carefully examined by scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and transmission electron microscopy. Three key findings resulted from this study. First, the Chi phase is stable at high temperature, and with decreasing temperature it transforms into the Laves phase that is stable at low temperature. Secondly, Cr, Mo, Ni are soluble in both the Chi and Laves phases, with the solubility of Mo playing a major role in the relative stability of the intermetallic phases. Thirdly, in situ transformation from Chi phase to Laves phase was directly observed, which increased the local strain field, generated dislocations in the intermetallic phases, and altered the precipitate phase orientation relationship with the austenitic matrix. The thermodynamic models that were developed and validated were then applied to evaluating the effect of Mo on the thermal stability of intermetallic phases in type 316 and NF709 stainless steels.

  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 ?P{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 ?P{sub c} magnitudes, especially for the compressional stress regime.

  13. Validation of a numerical model for the analysis of thermal-fluid behavior in a solar concentrator vessel

    E-Print Network [OSTI]

    Rodríguez Alvarado, Juan Fernando

    2010-01-01

    The need for innovation in the renewable energy sector is an ever-growing concern. With national-level disasters in the Gulf of Mexico, the necessity to begin the drive to develop effective and practical alternative energy ...

  14. Asymptotics and numerical efficiency of the Allen-Cahn model for phase interfaces with low energy in solids

    E-Print Network [OSTI]

    Hans-Dieter Alber

    2015-05-20

    The accurate simulation of phase interfaces in solids requires small model error and small numerical error. If a phase field model is used and the interface carries low interface energy, then the model error is only small if the interface width in the model is chosen small. Yet, for effective numerical computation the interface width should be large. Choosing the parameters, which determine the width, is therefore an optimality problem. We study this problem for the Allen-Cahn equation coupled to the elasticity equations by constructing an asymptotic solution of second order, which yields an expansion for the kinetic relation of the model. This expansion determines the choice of the parameters, however only if the difference between the expansion and the exact kinetic relation is uniformly small with respect to a second parameter controlling the interface energy. To show this uniformity we determine the asymptotics with respect to this second parameter by scaling of the model equations. Our investigations are formal.

  15. NUMERICAL MODELING OF THE COAGULATION AND POROSITY EVOLUTION OF DUST AGGREGATES

    SciTech Connect (OSTI)

    Okuzumi, Satoshi; Sakagami, Masa-aki [Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501 (Japan); Tanaka, Hidekazu, E-mail: satoshi.okuzumi@ax2.ecs.kyoto-u.ac.j [Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819 (Japan)

    2009-12-20

    Porosity evolution of dust aggregates is crucial in understanding dust evolution in protoplanetary disks. In this study, we present useful tools to study the coagulation and porosity evolution of dust aggregates. First, we present a new numerical method for simulating dust coagulation and porosity evolution as an extension of the conventional Smoluchowski equation. This method follows the evolution of the mean porosity for each aggregate mass simultaneously with the evolution of the mass distribution function. This method reproduces the results of previous Monte Carlo simulations with much less computational expense. Second, we propose a new collision model for porous dust aggregates on the basis of our N-body experiments on aggregate collisions. As the first step, we focus on 'hit-and-stick' collisions, which involve neither compression nor fragmentation of aggregates. We first obtain empirical data on porosity changes between the classical limits of ballistic cluster-cluster and particle-cluster aggregation. Using the data, we construct a recipe for the porosity change due to general hit-and-stick collisions as well as formulae for the aerodynamical and collisional cross sections. Our collision model is thus more realistic than a previous model of Ormel et al. based on the classical aggregation limits only. Simple coagulation simulations using the extended Smoluchowski method show that our collision model explains the fractal dimensions of porous aggregates observed in a full N-body simulation and a laboratory experiment. By contrast, similar simulations using the collision model of Ormel et al. result in much less porous aggregates, meaning that this model underestimates the porosity increase upon unequal-sized collisions. Besides, we discover that aggregates at the high-mass end of the distribution can have a considerably small aerodynamical cross section per unit mass compared with aggregates of lower masses. This occurs when aggregates drift under uniform acceleration (e.g., gravity) and their collision is induced by the difference in their terminal velocities. We point out an important implication of this discovery for dust growth in protoplanetary disks.

  16. Micro-chamber filling experiments for validation of macro models with applications in capillary driven microfluidics 

    E-Print Network [OSTI]

    Gauntt, Stephen Byron

    2009-05-15

    Prediction of bubble formation during filling of microchambers is often critical for determining the efficacy of microfluidic devices in various applications. In this study experimental validation is performed to verify the predictions from a...

  17. The motivations-attributes-skills-knowledge competency cluster validation model an empirical study 

    E-Print Network [OSTI]

    Stevens, Jeffery Allen

    2004-09-30

    This empirical research study had two main purposes with regard to competency cluster validation. First, this empirical research study was focused upon finding the gaps in the literature that existed pertaining to the Motivations...

  18. Direct-contact condensers for open-cycle OTEC applications: Model validation with fresh water experiments for structured packings

    SciTech Connect (OSTI)

    Bharathan, D.; Parsons, B.K.; Althof, J.A.

    1988-10-01

    The objective of the reported work was to develop analytical methods for evaluating the design and performance of advanced high-performance heat exchangers for use in open-cycle thermal energy conversion (OC-OTEC) systems. This report describes the progress made on validating a one-dimensional, steady-state analytical computer of fresh water experiments. The condenser model represents the state of the art in direct-contact heat exchange for condensation for OC-OTEC applications. This is expected to provide a basis for optimizing OC-OTEC plant configurations. Using the model, we examined two condenser geometries, a cocurrent and a countercurrent configuration. This report provides detailed validation results for important condenser parameters for cocurrent and countercurrent flows. Based on the comparisons and uncertainty overlap between the experimental data and predictions, the model is shown to predict critical condenser performance parameters with an uncertainty acceptable for general engineering design and performance evaluations. 33 refs., 69 figs., 38 tabs.

  19. Numerical modeling of the initial state and matching of well test data from the Zunil geothermal field, Guatemala

    SciTech Connect (OSTI)

    Menzies, A.J.; Granados, E.E.; Sanyal, .K.; Merida-I., L.; Caicedo-A, A.

    1991-01-01

    A significant amount of geoscientific and reservoir engineering data have been collected from the Zunil geothermal field since 1973. The data have been used to define a conceptual model for the field which has formed the basis for the construction of a three dimensional numerical simulation model. The numerical model has successfully matched both the initial state of the reservoir, as indicated by subsurface temperature and pressure distributions within the presently drilled area, and available well test data. The well test data include short and long term discharge tests and a comprehensive pressure interference test. Calibration of the model will continue during 1991 when the results from drilling and testing of three additional deep wells are available. The model will then be used to study various long term production scenarios for the proposed 15 MW power development.

  20. The VOLNA code for the numerical modelling of tsunami waves: generation, propagation and

    E-Print Network [OSTI]

    of the finite volume scheme implemented in the code. We explain the numerical treatment of the wet is decided on the base of inundation maps which are produced with this type of numerical tools. Finally we and the perspectives for future research presented. Key words: tsunami waves, shallow water equations, tsunami

  1. Numerical modeling of alongshore sediment transport and shoreline change along the Galveston coast 

    E-Print Network [OSTI]

    Sitanggang, Khairil Irfan

    2005-02-17

    coast for the period of 2001-2011. The first assessment shows that GENESIS has a numerical error which tends to be large for low energy wave (small breaking wave height) and large breaking wave angle. This numerical inaccuracy cannot be neglected...

  2. Numerical simulation of the 2011 Tohoku tsunami: Comparison with field observations and sensitivity to model parameters

    E-Print Network [OSTI]

    Kirby, James T.

    Numerical simulation of the 2011 Tohoku tsunami: Comparison with field observations and sensitivity history, created a major tsunami that caused numerous deaths and enormous destruction on the nearby Hon- shu coast. Various tsunami sources were developed for this event, based on inverting seismic or GPS

  3. SU-E-T-50: Automatic Validation of Megavoltage Beams Modeled for Clinical Use in Radiation Therapy

    SciTech Connect (OSTI)

    Melchior, M; Salinas Aranda, F; Sciutto, S; Dodat, D; Larragueta, N

    2014-06-01

    Purpose: To automatically validate megavoltage beams modeled in XiO™ 4.50 (Elekta, Stockholm, Sweden) and Varian Eclipse™ Treatment Planning Systems (TPS) (Varian Associates, Palo Alto, CA, USA), reducing validation time before beam-on for clinical use. Methods: A software application that can automatically read and analyze DICOM RT Dose and W2CAD files was developed using MatLab integrated development environment.TPS calculated dose distributions, in DICOM RT Dose format, and dose values measured in different Varian Clinac beams, in W2CAD format, were compared. Experimental beam data used were those acquired for beam commissioning, collected on a water phantom with a 2D automatic beam scanning system.Two methods were chosen to evaluate dose distributions fitting: gamma analysis and point tests described in Appendix E of IAEA TECDOC-1583. Depth dose curves and beam profiles were evaluated for both open and wedged beams. Tolerance parameters chosen for gamma analysis are 3% and 3 mm dose and distance, respectively.Absolute dose was measured independently at points proposed in Appendix E of TECDOC-1583 to validate software results. Results: TPS calculated depth dose distributions agree with measured beam data under fixed precision values at all depths analyzed. Measured beam dose profiles match TPS calculated doses with high accuracy in both open and wedged beams. Depth and profile dose distributions fitting analysis show gamma values < 1. Relative errors at points proposed in Appendix E of TECDOC-1583 meet therein recommended tolerances.Independent absolute dose measurements at points proposed in Appendix E of TECDOC-1583 confirm software results. Conclusion: Automatic validation of megavoltage beams modeled for their use in the clinic was accomplished. The software tool developed proved efficient, giving users a convenient and reliable environment to decide whether to accept or not a beam model for clinical use. Validation time before beam-on for clinical use was reduced to a few hours.

  4. 2250 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 A Numerical Model of Plasma-Actuator Effects

    E-Print Network [OSTI]

    Huang, Xun

    therein. Most recent ap- plications include high-speed flow control using localized arc filament plasma2250 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 37, NO. 11, NOVEMBER 2009 A Numerical Model of Plasma-Actuator Effects in Flow-Induced Noise Control Ed Peers, Xun Huang, and Xinfu Luo Abstract

  5. IMA Journal of Numerical Analysis (1988) 8, 415-433 Finite Element Methods for a Model for Full Waveform Acoustic

    E-Print Network [OSTI]

    Harrison, Mark

    1988-01-01

    IMA Journal of Numerical Analysis (1988) 8, 415-433 Finite Element Methods for a Model for Full are given and then a discrete-time, explicit finite element procedure is defined and analysed, with finite on the existence, uniqueness and finite element approximation of the solution of Biot's equations were given in [15

  6. LETTER Earth Planets Space, 63, 847851, 2011 Three-dimensional numerical modeling of tsunami-related internal gravity

    E-Print Network [OSTI]

    Occhipinti, Giovanni "Ninto"

    LETTER Earth Planets Space, 63, 847­851, 2011 Three-dimensional numerical modeling of tsunami, 2011; Accepted June 30, 2011; Online published September 27, 2011) The tremendous tsunami following, to reproduce the tsunami signature observed in the airglow by the imager located in Hawaii and clearly showing

  7. Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John, Ramprasad Balasubramanian and Amit Tandon*

    E-Print Network [OSTI]

    Tandon, Amit

    Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John suggested that the mesoscale eddies and mesoscale features play a strong role in carrying heat poleward oceanographers an invaluable tool to assess mesoscale eddies and the Lagrangian characteristics of this mesoscale

  8. Validation of Finite-Element Models of Persistent-Current Effects in Nb3Sn Accelerator Magnets

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

    Wang, X.; Ambrosio, G.; Chlachidze, G.; Collings, E. W.; Dietderich, D. R.; DiMarco, J.; Felice, H.; Ghosh, A. K.; Godeke, A.; Gourlay, S. A.; et al

    2015-01-06

    Persistent magnetization currents are induced in superconducting filaments during the current ramping in magnets. The resulting perturbation to the design magnetic field leads to field quality degradation, in particular at low field where the effect is stronger relative to the main field. The effects observed in NbTi accelerator magnets were reproduced well with the critical-state model. However, this approach becomes less accurate for the calculation of the persistent-current effects observed in Nb3Sn accelerator magnets. Here a finite-element method based on the measured strand magnetization is validated against three state-of-art Nb3Sn accelerator magnets featuring different subelement diameters, critical currents, magnet designsmore »and measurement temperatures. The temperature dependence of the persistent-current effects is reproduced. Based on the validated model, the impact of conductor design on the persistent current effects is discussed. The performance, limitations and possible improvements of the approach are also discussed.« less

  9. Calibration and Validation of a Spar-Type Floating Offshore Wind Turbine Model using the FAST Dynamic Simulation Tool: Preprint

    SciTech Connect (OSTI)

    Browning, J. R.; Jonkman, J.; Robertson, A.; Goupee, A. J.

    2012-11-01

    In 2007, the FAST wind turbine simulation tool, developed and maintained by the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL), was expanded to include capabilities that are suitable for modeling floating offshore wind turbines. In an effort to validate FAST and other offshore wind energy modeling tools, DOE funded the DeepCwind project that tested three prototype floating wind turbines at 1/50th scale in a wave basin, including a semisubmersible, a tension-leg platform, and a spar buoy. This paper describes the use of the results of the spar wave basin tests to calibrate and validate the FAST offshore floating simulation tool, and presents some initial results of simulated dynamic responses of the spar to several combinations of wind and sea states.

  10. Numerical study of the mass spectrum in the 2D O(3) sigma model with a theta term

    E-Print Network [OSTI]

    B. Alles; A. Papa

    2007-11-12

    It has been conjectured that the mass spectrum of the O(3) non-linear sigma model with a theta term in 2 dimensions may possess an excited state, which decays when theta is lowered from pi below a critical value. Since the direct numerical investigation of the model is prevented by a sign problem, we try to infer some information on the mass spectrum at real theta by studying the model at imaginary theta via analytic continuation. A modified Swendsen-Wang cluster algorithm has been introduced to simulate the model with the theta term.

  11. 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.

  12. HELIOSPHERIC PROPAGATION OF CORONAL MASS EJECTIONS: COMPARISON OF NUMERICAL WSA-ENLIL+CONE MODEL AND ANALYTICAL DRAG-BASED MODEL

    SciTech Connect (OSTI)

    Vršnak, B.; Žic, T.; Dumbovi?, M.; Temmer, M.; Möstl, C.; Veronig, A. M.; Taktakishvili, A.; Mays, M. L.; Odstr?il, D. E-mail: tzic@geof.hr E-mail: manuela.temmer@uni-graz.at E-mail: astrid.veronig@uni-graz.at E-mail: m.leila.mays@nasa.gov

    2014-08-01

    Real-time forecasting of the arrival of coronal mass ejections (CMEs) at Earth, based on remote solar observations, is one of the central issues of space-weather research. In this paper, we compare arrival-time predictions calculated applying the numerical ''WSA-ENLIL+Cone model'' and the analytical ''drag-based model'' (DBM). Both models use coronagraphic observations of CMEs as input data, thus providing an early space-weather forecast two to four days before the arrival of the disturbance at the Earth, depending on the CME speed. It is shown that both methods give very similar results if the drag parameter ? = 0.1 is used in DBM in combination with a background solar-wind speed of w = 400 km s{sup –1}. For this combination, the mean value of the difference between arrival times calculated by ENLIL and DBM is ?-bar =0.09±9.0 hr with an average of the absolute-value differences of |?|-bar =7.1 hr. Comparing the observed arrivals (O) with the calculated ones (C) for ENLIL gives O – C = –0.3 ± 16.9 hr and, analogously, O – C = +1.1 ± 19.1 hr for DBM. Applying ? = 0.2 with w = 450 km s{sup –1} in DBM, one finds O – C = –1.7 ± 18.3 hr, with an average of the absolute-value differences of 14.8 hr, which is similar to that for ENLIL, 14.1 hr. Finally, we demonstrate that the prediction accuracy significantly degrades with increasing solar activity.

  13. A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

    2013-01-01

    cycle:  The RUC.  Monthly Weather  Review.   132, 495?518.  th  Conference on  Numerical Weather Prediction.   American closure schemes.   Monthly Weather Review.   122, 927?945.  

  14. Soil Liquefaction–Induced Uplift of Underground Structures: Physical and Numerical Modeling

    E-Print Network [OSTI]

    Chian, Siau Chen; Tokimatsu, Kohji; M.ASCE; Madabhushi, Santana Phani Gopal

    2014-07-11

    in the liquefiable soil deposit. These consistencies with field observations clearly demonstrate and pave the prospects of applying numerical and/or experimental analyses for geotechnical problems associated with the floatation of underground structures...

  15. Numerical modeling of species transport in turbulent flow and experimental study on aerosol sampling 

    E-Print Network [OSTI]

    Vijayaraghavan, Vishnu Karthik

    2007-04-25

    Numerical simulations were performed to study the turbulent mixing of a scalar species in straight tube, single and double elbow flow configurations. Different Reynolds Averaged Navier Stokes (RANS) and Large Eddy Simulation ...

  16. Grid-Based Surrogate Reservoir Modeling (SRM) for Fast Track Analysis of Numerical Reservoir Simulation Models at the Grid block Level

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    capability of being able to replicate the pressure and saturation distribution throughout the reservoirSPE 153844 Grid-Based Surrogate Reservoir Modeling (SRM) for Fast Track Analysis of Numerical Reservoir Simulation Models at the Grid block Level Shahab D. Mohaghegh, West Virginia University

  17. Numerical method toward fast and accurate calculation of dilute quantum gas using Uehling-Uhlenbeck model equation

    E-Print Network [OSTI]

    Yano, Ryosuke

    2015-01-01

    We consider a fast and accurate numerical method to calculate the dilute quantum gas. To attain our aim, the Uehing-Uhlenbeck (U-U) model equation is calculated using the direct simulation Monte Carlo (DSMC) method. The proposed algorithm in the DSMC method enables us to obtain the accurate thermalization using a small number of sample particles and calculate the dilute quantum gas dynamics in practical time. Finally, we apply the proposed numerical method to the calculation of the viscosity coefficient on the basis of Green-Kubo expression.

  18. Qualification of the ITER CS Quench Detection System using Numerical Modeling

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL; Radovinsky, Alexey L [ORNL

    2013-01-01

    Abstract The ITER Central Solenoid (CS) magnet needs to be protected against overheating of the conductor in the event of the occurrence of a normal zone (NZ). Due to a large amount of stored energy and slow NZ propagation, the NZ needs to be detected and the switchyard needs to open the breakers within 2 s after detection of the NZ. The CS will be discharged on a dump resistor with a time constant of 7.5 s. During operation of the CS and its interaction with the poloidal field (PF) coils and plasma current, the CS experiences large inductive voltages from multiple sources, including nonlinear signals from eddy currents in the vacuum vessel and plasma current variation, that make the task of detecting the resistive signal even more difficult. This inductive voltage needs to be cancelled by quench detection (QD) hardware (e.g., bridges, converters, filters, processors) and appropriate processing of the QD signals to reliably detect NZ initiation and propagation. Two redundant schemes are proposed as the baseline for the CS QD System: 1) A scheme with Regular Voltage Taps (RVT) from triads of Double Pancakes (DP) supplemented by Central Difference Averaging (CDA) and by digital suppression of the inductive voltage from all active coils (the CS and PF coils). Voltage taps are taken from helium outlets at the CS outer diameter. 2)A scheme with Cowound Voltage Taps (CVT) taken from cowound wires routed from the helium inlet at the CS inner diameter. Summary of results of the numerical modeling of the performance of both baseline CS QD systems is presented in this paper. Index Terms Quench detection, Central Solenoid, ITER

  19. Knowledge Provenance: An Approach to Modeling and Maintaining The Evolution and Validity of Knowledge

    E-Print Network [OSTI]

    Fox, Mark S.

    with information of unknown sources, and need to interact with "strangers". This makes trust and the validity of information in cyberspace arise as crucial issues. This thesis proposes knowledge provenance (KP) as a formal and maintaining the information sources, information dependencies, and trust structures. We conceptualize

  20. UPDATE February 2012 - The Food Crises: Predictive validation of a quantitative model of food prices including speculators and ethanol conversion

    E-Print Network [OSTI]

    Lagi, Marco; Bertrand, Karla Z; Bar-Yam, Yaneer

    2012-01-01

    Increases in global food prices have led to widespread hunger and social unrest---and an imperative to understand their causes. In a previous paper published in September 2011, we constructed for the first time a dynamic model that quantitatively agreed with food prices. Specifically, the model fit the FAO Food Price Index time series from January 2004 to March 2011, inclusive. The results showed that the dominant causes of price increases during this period were investor speculation and ethanol conversion. The model included investor trend following as well as shifting between commodities, equities and bonds to take advantage of increased expected returns. Here, we extend the food prices model to January 2012, without modifying the model but simply continuing its dynamics. The agreement is still precise, validating both the descriptive and predictive abilities of the analysis. Policy actions are needed to avoid a third speculative bubble that would cause prices to rise above recent peaks by the end of 2012.

  1. Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)

    SciTech Connect (OSTI)

    Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

    2014-06-01

    Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

  2. Observation and numerical modeling of chromospheric evaporation during the impulsive phase of a solar flare

    E-Print Network [OSTI]

    Imada, Shinsuke; Watanabe, Tetsuya

    2015-01-01

    We have studied the chromospheric evaporation flow during the impulsive phase of the flare by using the Hinode/EIS observation and 1D hydrodynamic numerical simulation coupled to the time-dependent ionization. The observation clearly shows that the strong redshift can be observed at the base of the flaring loop only during the impulsive phase. We performed two different numerical simulations to reproduce the strong downflows in FeXII and FeXV during the impulsive phase. By changing the thermal conduction coefficient, we carried out the numerical calculation of chromospheric evaporation in the thermal conduction dominant regime (conductivity coefficient kappa0 = classical value) and the enthalpy flux dominant regime (kappa0 = 0.1 x classical value). The chromospheric evaporation calculation in the enthalpy flux dominant regime could reproduce the strong redshift at the base of the flare during the impulsive phase. This result might indicate that the thermal conduction can be strongly suppressed in some cases o...

  3. Biomarker Discovery and Validation for Proteomics and Genomics: Modeling And Systematic Analysis 

    E-Print Network [OSTI]

    Atashpazgargari, Esmaeil

    2014-08-27

    and Complexity of Decision Boundary . . . 7 1.1.3 Error Estimation Methods . . . . . . . . . . . . . . . . . . . . 8 1.2 Biomarker Validation: Selected Reaction Monitoring . . . . . . . . . 13 2. A FAST ALGORITHM FOR U-CURVE BRANCH-AND-BOUND FEA- TURE SELECTION... Efficiency of two algorithms vs. nFE. . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 2.8 (a) Plot of the average function evaluations used by each algorithm to find the optimal feature sets, with standard deviation bars. (b) Barplot of the average...

  4. Modelling and numerical approximation of a 2.5D set of equations for mesoscale atmospheric processes

    E-Print Network [OSTI]

    Kalise, Dante

    2011-01-01

    The set of 3D inviscid primitive equations for the atmosphere is dimensionally reduced by a Discontinuous Galerkin discretization in one horizontal direction. The resulting model is a 2D system of balance laws where with a source term depending on the layering procedure and the choice of coupling fluxes, which is established in terms of upwind considerations. The "2.5D" system is discretized via a WENO-TVD scheme based in a flux limiter centered approach. We study four tests cases related to atmospheric phenomena to analyze the physical validity of the model.

  5. An experimental validation of the PRO model for parallel and distributed computation

    E-Print Network [OSTI]

    Boyer, Edmond

    model was introduced by Gebremedhin et al. [2002] as a frame- work for the design and analysis. The Parallel Resource-Optimal (PRO) model, introduced in Gebremedhin et al. [2002], is similar to the BSP model discussion of the PRO model, see Gebremedhin et al. [2002]. The PRO model The key features of PRO

  6. On the modeling, design and validation of two dimensional quasi-static eddy current forces in a mechanical oscillator.

    SciTech Connect (OSTI)

    Mitchell, John Anthony; Epp, David S.; Wittwer, Jonathan W.

    2005-10-01

    Damping vibrations is important in the design of some types of inertial sensing devices. One method for adding damping to a device is to use magnetic forces generated by a static magnetic field interacting with eddy currents. In this report, we develop a 2-dimensional finite element model for the analysis of quasistatic eddy currents in a thin sheet of conducting material. The model was used for design and sensitivity analyses of a novel mechanical oscillator that consists of a shuttle mass (thin sheet of conducting material) and a set of folded spring elements. The oscillator is damped through the interaction of a static magnetic field and eddy currents in the shuttle mass. Using a prototype device and Laser Dopler Velocimetry (LDV), measurements were compared to the model in a validation study using simulation based uncertainty analyses. Measurements were found to follow the trends predicted by the model.

  7. Validation of Innovative Exploration Technologies for Newberry Volcano

    Broader source: Energy.gov [DOE]

    DOE Geothermal Technologies Peer Review - 2010. Project summary: To effectively combine numerous exploration technologies to gather important data. Once information is combined into 3-D models, a target drilling location will be determined. Deep well capable of finding commercial quantities of geothermal resource will be drilled to validate methodology.

  8. A three-dimensional numerical model of a micro laminar flow fuel cell with a bridge-shaped microchannel cross-section

    E-Print Network [OSTI]

    Kenis, Paul J. A.

    A three-dimensional numerical model of a micro laminar flow fuel cell with a bridge: Membraneless fuel cell Laminar flow fuel cell Numerical model Convection-diffusion equations Electrode kinetics equations COMSOL a b s t r a c t The operation of a laminar flow fuel cell (LFFC) involves complex interplay

  9. Remarks on numerical simulation of the PKN model of hydrofracturing in proper variables. Various leak-off regimes

    E-Print Network [OSTI]

    Kusmierczyk, P; Wrobel, M

    2012-01-01

    The problem of hydraulic fracture for the PKN model is considered within the framework of approach presented recently by Linkov (2011). The modified formulation is further enhanced by employing an improved regularized boundary condition near the crack tip. This increases solution accuracy especially for singular leak-off regimes. A new dependent variable having clear physical sense is introduced. A comprehensive analysis of numerical algorithms based on various dependent variables is provided.

  10. Holism and Entrenchment in Climate Model Validation J. Lenhard and E. Winsberg, draft March 7, 2008

    E-Print Network [OSTI]

    Winsberg, Eric B.

    of complex systems, particularly modelers of the earth's climate, face a deeply entrenched form models--with a particular emphasis on models of the earth's climate. The first claim is about holism. We, on the one hand, and the dynamics of the real world system to be modeled, on the other. To be sure

  11. Validating Modal Aspects of OntoUML Conceptual Models Using Automatically Generated Visual World

    E-Print Network [OSTI]

    Foundation Ontology (UFO). UFO is a foundational ontology designed specially for conceptual modeling

  12. Validating Modal Aspects of OntoUML Conceptual Models Using Automatically Generated Visual World

    E-Print Network [OSTI]

    Foundation Ontology (UFO). UFO is a foundational ontology designed specially for conceptual modeling l

  13. CASL - Initial Validation and Benchmark Study of new 3D CRUD Model

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L OBransenBusinessInitial Validation and Benchmark Study of new

  14. Validation of Global Weather Forecast and Climate Models Over the North

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentric viewingValidating extended MHDCERES/SARB DataSlope of

  15. An ultra-compact virtual source FET model for deeply-scaled devices: Parameter extraction and validation for standard cell libraries and digital circuits

    E-Print Network [OSTI]

    Mysore, Omar

    In this paper, we present the first validation of the virtual source (VS) charge-based compact model for standard cell libraries and large-scale digital circuits. With only a modest number of physically meaningful parameters, ...

  16. Elastic moduli of untreated, demineralized and deproteinized cortical bone: Validation of a theoretical model of bone as an interpenetrating composite material

    E-Print Network [OSTI]

    McKittrick, Joanna

    Elastic moduli of untreated, demineralized and deproteinized cortical bone: Validation online 15 November 2011 Keywords: Cortical bone Elastic moduli Multi-scale modeling Demineralization include completely demineralized and deproteinized bones as well as untreated bone samples. Porosity

  17. Validity of the Generalized Second Law of Thermodynamics of the Universe Bounded by the Event Horizon in Holographic Dark Energy Model

    E-Print Network [OSTI]

    Nairwita Mazumder; Subenoy Chakraborty

    2010-05-19

    In this letter, we investigate the validity of the generalized second law of thermodynamics of the universe bounded by the event horizon in the holographic dark energy model. The universe is chosen to be homogeneous and isotropic and the validity of the first law has been assumed here. The matter in the universe is taken in the form of non-interacting two fluid system- one component is the holographic dark energy model and the other component is in the form of dust.

  18. THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01

    disposal of radioactive waste: The Sandia waste isolation flow and transport (SWIFT) model: Sandia Laboratories Report

  19. Development and Validation of a Computer Model for Energy-Efficient Shaded Fenestration Design 

    E-Print Network [OSTI]

    Oh, Kie Whan

    2000-01-01

    transfer through an unshaded window at any orientation. A computerized simulation model, called the Shaded Fenestration Design (SFD) model, was developed that is capable of calculating the amount of solar radiation for a clear day as well as calculating...

  20. Model-Based Validation of QoS Properties of Biomedical Sensor Networks

    E-Print Network [OSTI]

    Yi, Wang

    is supported by EC IST project CREDO. All models for the experiments of this work can be found at http

  1. Validation of a Cognitive Diagnostic Model Across Multiple Forms of a Reading Comprehension Assessment

    E-Print Network [OSTI]

    Clark, Amy K

    2013-12-31

    testing programs have begun implementing cognitive diagnostic modeling with tests that are already in use. In this process, a cognitive model is retrofit to a test form using... large testing organizations. Rather than retrofitting a diagnostic model to a single test form at a time, operational testing programs would benefit from being able to apply...

  2. Validation of a Model and a Simulator for Road Cycling on Real Tracks Thorsten Dahmen Roman Byshko Dietmar Saupe Martin Roder Stephan

    E-Print Network [OSTI]

    Deussen, Oliver

    from the law of conservation of energy. The state-of-the art mathematical model for road cycling powerValidation of a Model and a Simulator for Road Cycling on Real Tracks Thorsten Dahmen · Roman acquisition, analy- sis, modelling, and simulation of performance parameters in road cycling on real tracks

  3. Mathematical Models and Numerical Simulations of phase change in Lagrangian and Eulerian descriptions

    E-Print Network [OSTI]

    Quiros Fonseca, Luis Alonso

    2012-12-31

    This thesis presents development of mathematical models for liquid-solid and solid-liquid phase change phenomena in Lagrangian and Eulerian descriptions. The mathematical models are derived by assuming a smooth interface ...

  4. Use of international data sets to evaluate and validate pathway assessment models applicable to exposure and dose reconstruction at DOE facilities. Progress report, August 1993--January 1994

    SciTech Connect (OSTI)

    Hendrickson, S.M.; Hoffman, F.O.

    1994-03-01

    This project, ``Use of International Data Sets to Evaluate and Validate Pathway Assessment Models Applicable to Exposure and Dose Reconstruction at DOE Facilities,`` grew out of several activities being conducted by the Principal Investigator Dr. F Owen Hoffman. One activity was originally part of the Chernobyl Studies Project and began as Task 7.1D, ``Internal Dose From Direct Contamination of Terrestrial Food Sources.`` The objective of Task 7.1D was to (1) establish a collaborative US USSR effort to improve and validate our methods of forecasting doses and dose commitments from the direct contamination of food sources, and (2) perform experiments and validation studies to improve our ability to predict rapidly and accurately the long-term internal dose from the contamination of agricultural soil. The latter was to include the consideration of remedial measures to block contamination of food grown on contaminated soil. The current objective of this project is to evaluate and validate pathway-assessment models applicable to exposure and dose reconstruction at DOE facilities through use of international data sets. This project incorporates the activity of Task 7.1D into a multinational effort to evaluate data used for the prediction of radionuclide transfer through agricultural and aquatic systems to humans. It also includes participation in two multinational studies, BIOMOVS (BIOspheric MOdel Validation Study) with the Swedish National Institute for Radiation Protection and VAMP (VAlidation of Model Predictions) with the International Atomic Energy Agency, that address testing the performance of models of radionuclide transport through foodchains.

  5. THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01

    improving production by hydraulic fracturing 8 the focus otfor fractures. (d) Hydraulic Fracturing: The model has been

  6. On The Validity of the Streaming Model for the Redshift-Space Correlation Function in the Linear Regime

    E-Print Network [OSTI]

    Karl B. Fisher

    1994-12-20

    The relation between the galaxy correlation function in real and redshift-space is derived in the linear regime by an appropriate averaging of the joint probability distribution of density and velocity. The derivation recovers the familiar linear theory result on large scales but has the advantage of clearly revealing the dependence of the redshift distortions on the underlying peculiar velocity field; streaming motions give rise to distortions of ${\\cal O}(\\Omega^{0.6}/b)$ while variations in the anisotropic velocity dispersion yield terms of order ${\\cal O}(\\Omega^{1.2}/b^2)$. This probabilistic derivation of the redshift-space correlation function is similar in spirit to the derivation of the commonly used ``streaming'' model, in which the distortions are given by a convolution of the real-space correlation function with a velocity distribution function. The streaming model is often used to model the redshift-space correlation function on small, highly non-linear, scales. There have been claims in the literature, however, that the streaming model is not valid in the linear regime. Our analysis confirms this claim, but we show that the streaming model can be made consistent with linear theory {\\it provided} that the model for the streaming has the functional form predicted by linear theory and that velocity distribution is chosen to be a Gaussian with the correct linear theory dispersion.

  7. STRUCTURAL VALIDATION OF SYSTEM DYNAMICS AND AGENT-BASED SIMULATION MODELS

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    , population dynamics, energy systems, and urban planning. The usefulness of these models is predicated including global warming, population dynamics, energy systems, and urban planning simply defy a face

  8. Experimentally Validated Compatibility Strut and Tie Modeling of Reinforced Concrete Bridge Piers 

    E-Print Network [OSTI]

    Scott, Reece Melby

    2010-10-12

    A compatibility-based strut-and-tie model C-STM is proposed for analyzing deep beams and disturbed regions with particular emphasis on reinforced concrete bridge piers. In addition to the normal strut-and-tie force equilibrium requirements the model...

  9. Validation of a STATCOM Transient Stability Model through Small-Disturbance Stability Studies

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    . INTRODUCTION Power system operators are constantly striving to keep power networks secure by guaranteeing models. For instance, the TS models proposed for a series of Flexible AC Transmission Systems (FACTS used in small-disturbance stability studies of large, interconnected power grids as well as microgrids

  10. Development and Validation of an Analogue Lumbar Spine Model and its Integral Components

    E-Print Network [OSTI]

    Domann, John P.

    2011-04-25

    There is a large need for an anatomically and mechanically correct model of the human lumbar spine. Such a model could have widespread use in the development of new implants and surgical procedures designed to remediate low back pain. Previous work...

  11. Description and preliminary validation of a model for natural convection heat and air transport in passive solar buildings

    SciTech Connect (OSTI)

    Jones, G.F.; Balcomb, J.D.

    1985-01-01

    We have proposed a transient, quasi-two-dimensional, numerical model for interzone heat flow and airflow in passive solar buildings. The paths for heat flow and airflow are through connecting apertures such as doorways, hallways, and stairways. The model includes the major features that influence interzone convection as determined from the results of our flow visualization tests and temperature and airflow measurements taken in more than a dozen passive solar buildings. The model includes laminar and turbulent quasi-steady boundary-layer equations at vertical heated or cooled walls which are coupled to a one-dimensional core model for each zone. The cores in each zone exchange air and energy through the aperture which is modelled by a Bernoulli equation. Preliminary results from the model are in general agreement with data obtained in full-scale buildings and laboratory experiments. The model predicts room-core temperature stratification of about 2/sup 0/C/m (1.1/sup 0/ F/ft) and maximum aperture velocities of 0.08 m/s (15 ft/min.) for a room-to-room temperature difference of 1/sup 0/F.

  12. Model-based PSF and MTF estimation and validation from skeletal clinical CT images

    SciTech Connect (OSTI)

    Pakdel, Amirreza; Mainprize, James G.; Robert, Normand; Fialkov, Jeffery; Whyne, Cari M.

    2014-01-15

    Purpose: A method was developed to correct for systematic errors in estimating the thickness of thin bones due to image blurring in CT images using bone interfaces to estimate the point-spread-function (PSF). This study validates the accuracy of the PSFs estimated using said method from various clinical CT images featuring cortical bones. Methods: Gaussian PSFs, characterized by a different extent in the z (scan) direction than in the x and y directions were obtained using our method from 11 clinical CT scans of a cadaveric craniofacial skeleton. These PSFs were estimated for multiple combinations of scanning parameters and reconstruction methods. The actual PSF for each scan setting was measured using the slanted-slit technique within the image slice plane and the longitudinal axis. The Gaussian PSF and the corresponding modulation transfer function (MTF) are compared against the actual PSF and MTF for validation. Results: The differences (errors) between the actual and estimated full-width half-max (FWHM) of the PSFs were 0.09 ± 0.05 and 0.14 ± 0.11 mm for the xy and z axes, respectively. The overall errors in the predicted frequencies measured at 75%, 50%, 25%, 10%, and 5% MTF levels were 0.06 ± 0.07 and 0.06 ± 0.04 cycles/mm for the xy and z axes, respectively. The accuracy of the estimates was dependent on whether they were reconstructed with a standard kernel (Toshiba's FC68, mean error of 0.06 ± 0.05 mm, MTF mean error 0.02 ± 0.02 cycles/mm) or a high resolution bone kernel (Toshiba's FC81, PSF FWHM error 0.12 ± 0.03 mm, MTF mean error 0.09 ± 0.08 cycles/mm). Conclusions: The method is accurate in 3D for an image reconstructed using a standard reconstruction kernel, which conforms to the Gaussian PSF assumption but less accurate when using a high resolution bone kernel. The method is a practical and self-contained means of estimating the PSF in clinical CT images featuring cortical bones, without the need phantoms or any prior knowledge about the scanner-specific parameters.

  13. Atmospheric Test Models and Numerical Experiments for the Simulation of the Global Distributions of Weather Data Transponders III. Horizontal Distributions

    SciTech Connect (OSTI)

    Molenkamp, C.R.; Grossman, A.

    1999-12-20

    A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show that reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.

  14. Spectral modeling of two incline cylinders with validation in the time domain 

    E-Print Network [OSTI]

    Oswalt, Aaron Jacob

    1999-01-01

    Function. 2. 3 Two Input/Single Output System . 2. 4 Conditioned Spectral Analysis. 2. 5 Partial Coherence 2. 6 Formulation of the Nonlinear Model 2. 6. 1 Nonlinear System Form . . 2. 6. 2 Reverse Dynamic Nonlinear System. 2. 6. 3 SDOF Nonlinear...) . . . . . . . . . . . . . . . 15 5 SVSO model for two-input system used to remove the correlated effects of xr(r) . . 18 6 Conditioned spectral model with noise for a two-input / single-output system . . . . . . 20 7 Classification of interference regions for inline...

  15. Validation of nuclear models in Geant4 using the halo of a proton pencil beam stopping in water

    E-Print Network [OSTI]

    Hall, David C; Paganetti, Harald; Gottschalk, Bernard

    2015-01-01

    A proton pencil beam is associated with a surrounding low-dose envelope, originating from nuclear interactions. It is important for treatment planning systems to accurately model this envelope when performing dose calculations for pencil beam scanning treatments, and Monte Carlo (MC) codes are commonly used for this purpose. This work aims to validate the nuclear models employed by the Geant4 MC code, by comparing the simulated absolute dose distribution to a recent experiment of a 177 MeV proton pencil beam stopping in water. Impressive agreement is observed over five orders of magnitude, with both the shape and normalisation well modelled. The normalisations of two depth dose curves are lower than experiment, though this could be explained by an experimental positioning error. The Geant4 neutron production model is also verified in the distal region. The entrance dose is poorly modelled, suggesting an unaccounted upstream source of low-energy protons. Recommendations are given for a follow-up experiment whi...

  16. Atmospheric test models and numerical experiments for the simulation of the global distribution of weather data transponders

    SciTech Connect (OSTI)

    Grossman, A; Molenkamp, C R

    1999-08-25

    A proposal has been made to establish a high density global network of atmospheric micro transponders to record time, temperature, and wind data with time resolution of {le} 1 minute, temperature accuracy of {+-} 1 K, spatial resolution no poorer than {approx}3km horizontally and {approx}0.1km vertically, and 2-D speed accuracy of {le} 1m/s. This data will be used in conjunction with advanced numerical weather prediction models to provide increases in the reliability of long range weather forecasts. Major advances in data collection technology will be required to provide the proposed high-resolution data collection network. Systems studies must be undertaken to determine insertion requirements, spacing, and evolution of the transponder ensemble, which will be used to collect the data. Numerical models which provide realistic global weather pattern simulations must be utilized in order to perform these studies. A global circulation model with a 3{sup o} horizontal resolution has been used for initial simulations of the generation and evolution of transponder distributions. These studies indicate that reasonable global coverage of transponders can be achieved by a launch scenario consisting of the sequential launch of transponders at specified heights from a globally distributed set of launch sites.

  17. A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

    2013-01-01

    of the WRF model solar irradiance forecasts in Andalusia (Beyer, H. , 2009.    Irradiance forecasting for the power dependent probabilistic irradiance  forecasts for coastal 

  18. THE STATE OF THE ART OF NUMERICAL MODELING OF THERMOHYDROLOGIC FLOW IN FRACTURED ROCK MASSES

    E-Print Network [OSTI]

    Wang, J.S.Y.

    2013-01-01

    thermal calculations for the WIPP site in southeastern NewWaste Isolation Pilot Plant (WIPP) in bedded salt. The codepersonal communication 1980). WIPP The modeling for WIPP is

  19. A Numerical Model For The Dynamics Of Pyroclastic Flows At Galeras...

    Open Energy Info (EERE)

    a topographic barrier located more than 16 km from the source. Two initial solid volumetric fractions are modeled. For both cases, some of the structures located more distant...

  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. Development of a Colon Cancer GEMM-Derived Orthotopic Transplant Model for Drug Discovery and Validation

    E-Print Network [OSTI]

    Martin, E. S.

    Purpose: Effective therapies for KRAS-mutant colorectal cancer (CRC) are a critical unmet clinical need. Previously, we described genetically engineered mouse models (GEMM) for sporadic Kras-mutant and non-mutant CRC ...

  2. Validation of a molecular hydrogen penetration model in the electric tokamak

    E-Print Network [OSTI]

    Gourdain, P A

    2006-01-01

    chamber of the Electric Tokamak showing bare walls andModel in the Electric Tokamak P. -A. Gourdain a) , L. W.of fusion devices such as tokamaks. In low density plasmas,

  3. New methods for estimation, modeling and validation of dynamical systems using automatic differentiation 

    E-Print Network [OSTI]

    Griffith, Daniel Todd

    2005-02-17

    The main objective of this work is to demonstrate some new computational methods for estimation, optimization and modeling of dynamical systems that use automatic differentiation. Particular focus will be upon dynamical ...

  4. Dynamic Modeling and Wavelet-Based Multi-Parametric Tuning and Validation for HVAC Systems 

    E-Print Network [OSTI]

    Liang, Shuangshuang

    2014-07-10

    Dynamic Heating, Ventilation, and Air-Conditioning (HVAC) system models are used for the purpose of control design, fault detection and diagnosis, system analysis, design and optimization. Therefore, ensuring the accuracy ...

  5. Development and validation of an analytical model for the notched pocket damper seal 

    E-Print Network [OSTI]

    Kannan Srinivas, Bharathwaj

    2004-09-30

    Experiments conducted at the Texas A&M Turbomachinery Laboratory and field applications have shown that pocket damper seals (PDS) can be used to suppress vibrations in compressors. A mathematical model is presented for the notched PDS. The notch...

  6. Soundfield simulation : the prediction and validation of acoustical behavior with compute models

    E-Print Network [OSTI]

    Saad, Omar, 1974-

    2004-01-01

    In the past, acoustical consultants could only try to convince the client/architect that with calculations and geometrical plots they could create an acoustically superb space. Now, by modeling the significant acoustical ...

  7. Validation of Model Simulations of Anvil Cirrus Properties During TWP-ICE: Final Report

    SciTech Connect (OSTI)

    Zipser, Edward J. [University of Utah] [University of Utah

    2013-05-20

    This 3-year grant, with two extensions, resulted in a successful 5-year effort, led by Ph.D. student Adam Varble, to compare cloud resolving model (CRM) simulations with the excellent database obtained during the TWP-ICE field campaign. The objective, largely achieved, is to undertake these comparisons comprehensively and quantitatively, informing the community in ways that goes beyond pointing out errors in the models, but points out ways to improve both cloud dynamics and microphysics parameterizations in future modeling efforts. Under DOE support, Adam Varble, with considerable assistance from Dr. Ann Fridlind and others, entrained scientists who ran some 10 different CRMs and 4 different limited area models (LAMs) using a variety of microphysics parameterizations, to ensure that the conclusions of the study will have considerable generality.

  8. A unified numerical model of collisional depolarization and broadening rates due to hydrogen atom collisions

    E-Print Network [OSTI]

    Derouich, M; Barklem, P S

    2015-01-01

    Interpretation of solar polarization spectra accounting for partial or complete frequency redistribution requires data on various collisional processes. Data for depolarization and polarization transfer are needed but often missing, while data for collisional broadening are usually more readily available. Recent work by Sahal-Br\\'echot and Bommier concluded that despite underlying similarities in the physics of collisional broadening and depolarization processes, relationships between them are not possible to derive purely analytically. We aim to derive accurate numerical relationships between the collisional broadening rates and the collisional depolarization and polarization transfer rates due to hydrogen atom collisions. Such relationships would enable accurate and efficient estimation of collisional data for solar applications. Using earlier results for broadening and depolarization processes based on general (i.e. not specific to a given atom), semi-classical calculations employing interaction potentials...

  9. Interstellar hydrogen fluxes measured by IBEX-Lo in 2009: numerical modeling and comparison with the data

    E-Print Network [OSTI]

    Katushkina, O A; Alexashov, D B; Schwadron, N A; McComas, D J

    2015-01-01

    In this paper, we perform numerical modeling of the interstellar hydrogen fluxes measured by IBEX-Lo during orbit 23 (spring 2009) using a state-of-the-art kinetic model of the interstellar neutral hydrogen distribution in the heliosphere. This model takes into account the temporal and heliolatitudinal variations of the solar parameters as well as non-Maxwellian kinetic properties of the hydrogen distribution due to charge exchange in the heliospheric interface. We found that there is a qualitative difference between the IBEX-Lo data and the modeling results obtained with the three-dimensional, time-dependent model. Namely, the model predicts a larger count rate in energy bin~2 (20-41 eV) than in energy bin~1 (11-21 eV), while the data shows the opposite case. We perform study of the model parameter effects on the IBEX-Lo fluxes and the ratio of fluxes in two energy channels. We shown that the most important parameter, which has a major influence on the ratio of the fluxes in the two energy bins, is the solar...

  10. / free-slip / free-slip Numerical models of slab deformation in the upper mantle

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    of the plate. Model: Model domain: Results: Effect of decoupling mechanism 410 km 660 km oceánska doska nadlozná doska Results: Effect of boundary condition Effect of yield stress Plate velocity Kinematic, crust.s 1020 Pa.s 1021 Pa.s Free-slip, crust = 1020 Pas, y = 108 Pa Kinematic, crust = 1020 Pas, y = 109 Pa

  11. NUMERICAL MODELING FOR THE FORMATION MECHANISM OF 3D TOPOGRAPHY ON MICROBIAL MAT SURFACES 

    E-Print Network [OSTI]

    Patel, Harsh Jay

    2013-09-27

    a node in the fluid to solid (aggregate or the particle) ? b number of discrete velocities 14 In order to stochastically solve the stochastic solute diffusion equation (Eq. 6), initial and boundary conditions are specified before solving...) Model........................................... 1.2.2 The Diffusion Limited Aggregation-Cellular Automata (DLA-CA) Model................................................................................................ 1.2.3 The Reaction-Diffusion...

  12. Simulation of a Polar Low Case in the North Atlantic with different regional numerical models

    E-Print Network [OSTI]

    Zahn, Matthias

    by the DWD (German Weather Service) by means of their forecast model HRM (High Resolution Model) and another University Press, Cambridge. (a) CLM (b) REMO (c) HRM, DWD (d) BWK Figure 1: 1(a)- 1(c)10m wind velocity pressure from CLM and REMO simulations and HRM analysis, DWD, respectively, at 15/10/93, 6:00, 1(d) surface

  13. Well-characterized open pool experiment data and analysis for model validation and development.

    SciTech Connect (OSTI)

    Sundberg, David W.; Brown, Alexander L.; Blanchat, Thomas K.

    2006-12-01

    Four Well-Characterized Open Pool fires were conducted by Fire Science and Technology Department. The focus of the Well-Characterized Open Pool fire series was to provide environmental information for open pool fires on a physics first principal basis. The experiments measured the burning rate of liquid fuel in an open pool and the resultant heat flux to a weapon-sized object and the surrounding environment with well-characterized boundary and initial conditions. Results presented in this report include a general description of test observation (pre- and post-test), wind measurements, fire plume topology, average fuel recession and heat release rates, and incident heat flux to the pool and to the calorimeters. As expected, results of the experiments show a strong correlation between wind conditions, fuel vaporization (mass loss) rate, and incident heat flux to the fuel and ground surface and calorimeters. Numerical fire simulations using both temporally- and spatially-dependant wind boundary conditions were performed using the Vulcan fire code. Comparisons of data to simulation predictions showed similar trends; however, simulation-predicted incident heat fluxes were lower than measured.

  14. Experiments to Populate and Validate a Processing Model for Polyurethane Foam: Additional Data for Structural Foams.

    SciTech Connect (OSTI)

    Rao, Rekha R.; Celina, Mathias C.; Giron, Nicholas Henry; Long, Kevin Nicholas; Russick, Edward M.

    2015-01-01

    We are developing computational models to help understand manufacturing processes, final properties and aging of structural foam, polyurethane PMDI. Th e resulting model predictions of density and cure gradients from the manufacturing process will be used as input to foam heat transfer and mechanical models. BKC 44306 PMDI-10 and BKC 44307 PMDI-18 are the most prevalent foams used in structural parts. Experiments needed to parameterize models of the reaction kinetics and the equations of motion during the foam blowing stages were described for BKC 44306 PMDI-10 in the first of this report series (Mondy et al. 2014). BKC 44307 PMDI-18 is a new foam that will be used to make relatively dense structural supports via over packing. It uses a different catalyst than those in the BKC 44306 family of foams; hence, we expect that the reaction kineti cs models must be modified. Here we detail the experiments needed to characteriz e the reaction kinetics of BKC 44307 PMDI-18 and suggest parameters for the model based on these experiments. In additi on, the second part of this report describes data taken to provide input to the preliminary nonlinear visco elastic structural response model developed for BKC 44306 PMDI-10 foam. We show that the standard cu re schedule used by KCP does not fully cure the material, and, upon temperature elevation above 150 o C, oxidation or decomposition reactions occur that alter the composition of the foam. These findings suggest that achieving a fully cured foam part with this formulation may be not be possible through therma l curing. As such, visco elastic characterization procedures developed for curing thermosets can provide only approximate material properties, since the state of the material continuously evolves during tests.

  15. Validity and sensitivity of a model for assessment of impacts of river floodplain reconstruction on protected and endangered species

    SciTech Connect (OSTI)

    Nooij, R.J.W. de [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands) and Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands)]. E-mail: R.deNooij@science.ru.nl; Lotterman, K.M. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Sande, P.H.J. van de [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Pelsma, T. [Institute for Inland Water Management and Waste Water Treatment (RIZA), P.O. Box 17, 8200 AA Lelystad (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands); Leuven, R.S.E.W. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands); Lenders, H.J.R. [Department of Environmental Science, Institute for Wetland and Water Research, Faculty of Science, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Netherlands Centre for River Studies (NCR), P.O. Box 177, 2600 MH Delft (Netherlands)

    2006-11-15

    Environmental Impact Assessment (EIA) must account for legally protected and endangered species. Uncertainties relating to the validity and sensitivity of EIA arise from predictions and valuation of effects on these species. This paper presents a validity and sensitivity analysis of a model (BIO-SAFE) for assessment of impacts of land use changes and physical reconstruction measures on legally protected and endangered river species. The assessment is based on links between species (higher plants, birds, mammals, reptiles and amphibians, butterflies and dragon- and damselflies) and ecotopes (landscape ecological units, e.g., river dune, soft wood alluvial forests), and on value assignment to protected and endangered species using different valuation criteria (i.e., EU Habitats and Birds directive, Conventions of Bern and Bonn and Red Lists). The validity of BIO-SAFE has been tested by comparing predicted effects of landscape changes on the diversity of protected and endangered species with observed changes in biodiversity in five reconstructed floodplains. The sensitivity of BIO-SAFE to value assignment has been analysed using data of a Strategic Environmental Assessment concerning the Spatial Planning Key Decision for reconstruction of the Dutch floodplains of the river Rhine, aimed at flood defence and ecological rehabilitation. The weights given to the valuation criteria for protected and endangered species were varied and the effects on ranking of alternatives were quantified. A statistically significant correlation (p < 0.01) between predicted and observed values for protected and endangered species was found. The sensitivity of the model to value assignment proved to be low. Comparison of five realistic valuation options showed that different rankings of scenarios predominantly occur when valuation criteria are left out of the assessment. Based on these results we conclude that linking species to ecotopes can be used for adequate impact assessments. Quantification of sensitivity of impact assessment to value assignment shows that a model like BIO-SAFE is relatively insensitive to assignment of values to different policy and legislation based criteria. Arbitrariness of the value assignment therefore has a very limited effect on assessment outcomes. However, the decision to include valuation criteria or not is very important.

  16. Testing the validity of the Kirkwood approximation using an extended Sznajd model

    E-Print Network [OSTI]

    Timpanaro, André Martin

    2015-01-01

    We revisit the deduction of the exit probability of the one dimensional Sznajd model through the Kirkwood approximation [F. Slanina et al., Europhys. Lett. 82, 18006 (2008)]. This approximation is peculiar in that in spite of the agreement with simulation results [F. Slanina et al., Europhys. Lett. 82, 18006 (2008), R. Lambiotte and S. Redner, Europhys. Lett. 82, 18007 (2008), A. M. Timpanaro and C. P. C. Prado, 89, 052808 (2014)] the hypothesis about the correlation lenghts behind it are inconsistent and fixing these inconsistencies leads to the same results as a simple mean field. We use an extended version of the Sznajd model to test the Kirkwood approximation in a wider context. This model includes the voter, Sznajd and "United we Stand, Divided we Fall" (USDF) models [R. A. Holley and T. M. Liggett, Ann. Prob. 3, 643 (1975), K. Sznajd-Weron and J. Sznajd, Int. Journ. Mod. Phys. C 11, 1157 (2000)] as different parameter combinations, meaning that some analytical results from these models can be used to ev...

  17. Controls on advance of tidewater glaciers: results from numerical modeling applied to Columbia Glacier

    E-Print Network [OSTI]

    Nick, F. M.; van der Veen, Cornelis J.; Oerlemans, J.

    2007-07-11

    at the glacier terminus and presented the flotation model. In the flotation model the terminus position is defined as the point where the ice thickness exceeds the flotation thickness by an amount H0. If the glacier thins, the terminus will retreat to a point... where this condition is again satisfied. Vieli et al. [2001] modified the flotation criterion and defined the thickness in excess of flotation H0 as a fraction of the flotation thickness. A recent modeling study by Nick and Oerlemans [2006] compared both...

  18. A simplified numerical model of coronal energy dissipation based on reduced MHD

    E-Print Network [OSTI]

    E. Buchlin; V. Aletti; S. Galtier; M. Velli; G. Einaudi; J. -C. Vial

    2003-03-27

    A 3D model intermediate between cellular automata (CA) models and the reduced magnetohydrodynamic (RMHD) equations is presented to simulate solar impulsive events generated along a coronal magnetic loop. The model consists of a set of planes distributed along a magnetic loop between which the information propagates through Alfven waves. Statistical properties in terms of power-laws for energies and durations of dissipative events are obtained, and their agreement with X-ray and UV flares observations is discussed. The existence of observational biases is also discussed.

  19. Numerical Modeling of the Transient Thermal Interference of Vertical U-Tube Haet Exchangers 

    E-Print Network [OSTI]

    Muraya, Norman K.

    1994-01-01

    Non-linear finite element models were developed to simulate transient heat and mass transfer in the soil surrounding the ground heat exchangers of ground-coupled heat pumps (GCHPs) operating in the cooling mode. Parametric ...

  20. Numerical and analytical modeling of heat transfer between fluid and fractured rocks

    E-Print Network [OSTI]

    Li, Wei, S.M. Massachusetts Institute of Technology

    2014-01-01

    Modeling of heat transfer between fluid and fractured rocks is of particular importance for energy extraction analysis in EGS, and therefore represents a critical component of EGS design and performance evaluation. In ...

  1. Numerical Modeling of Fractured Shale-Gas and Tight-Gas Reservoirs Using Unstructured Grids 

    E-Print Network [OSTI]

    Olorode, Olufemi Morounfopefoluwa

    2012-02-14

    Various models featuring horizontal wells with multiple induced fractures have been proposed to characterize flow behavior over time in tight gas and shale gas systems. Currently, there is little consensus regarding the effects of non...

  2. An Efficient Numerical Scheme for Simulating Unidirectional Irregular Waves Based on a Hybrid Wave Model 

    E-Print Network [OSTI]

    Jia, Dongxing 1984-

    2012-11-15

    The Unidirectional Hybrid Wave Model (UHWM) predicts irregular wave kinematics and pressure accurately in comparison with its linear counterpart and modification, especially near the free surface. Hence, in using the Morrison equation it has been...

  3. Final Report: A Model Management System for Numerical Simulations of Subsurface Processes

    SciTech Connect (OSTI)

    Zachmann, David

    2013-10-07

    The DOE and several other Federal agencies have committed significant resources to support the development of a large number of mathematical models for studying subsurface science problems such as groundwater flow, fate of contaminants and carbon sequestration, to mention only a few. This project provides new tools to help decision makers and stakeholders in subsurface science related problems to select an appropriate set of simulation models for a given field application.

  4. Validation of and enhancements to an operating-speed-based geometric design consistency evaluation model 

    E-Print Network [OSTI]

    Collins, Kent Michael

    1995-01-01

    .05 significance level. Analysis of observed 85th percentile speeds revealed that the current speed-profile model fits the observed data reasonably well. Hypothesis tests of mean observed 85th percentile speeds on tangents resulted in the conclusion that the mean...

  5. VALIDATION OF THE SUNY SATELLITE MODEL IN A METEOSAT ENVIRONMENT Richard Perez

    E-Print Network [OSTI]

    Perez, Richard R.

    ]. In this paper we evaluate the model's performance with another set of satellites: the European Meteosat 5 and 7 NREL, 1617 Cole Blvd. Golden, CO 80847 David_renne@nrel.gov Shannon Cowlin NREL Shannon_cowlin@nrel.gov Ray George NREL Ray_george@nrel.gov Bibek Bandyopadhyay Solar Energy Centre New Delhi, India bbibek

  6. Development and validation of a combustion model for a fuel cell off-gas burner

    E-Print Network [OSTI]

    Collins, William Tristan

    2008-10-14

    Burner Details 164 C.1 Burner Inlet Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 C.2 Emission Indices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 List of References 173 List of Figures 1.1 SOFC... Steady Laminar Flamelet Model . . . . . . . . . . . . . . . . . . . . . . 16 SOFC Solid Oxide Fuel Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 UDF User De?ned Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73...

  7. CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL

    E-Print Network [OSTI]

    Heinemann, Detlev

    between two different core radiation transfer models that will be applied during the SWERA (Solar and Wind ­ 048°31'42"W / 10m) 2. BASIC DESCRIPTION OF SOLAR RADIATION SITES The two sites were chosen because they provide high quality radiation data and represent different climatic/environmental regions and different

  8. Data gathering to build and validate small-scale social models for simulation. Two ways: strict control and stake-holders involvement

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Data gathering to build and validate small-scale social models for simulation. Two ways: strict. Nowadays, it has become a norm to assess results with actually comparable data and to build the hypothesis for the right use of empirical data in the building of models (Moss and Edmonds, 2005). In this paper, we focus

  9. Autoignition measurements and a validated kinetic model for the biodiesel surrogate, methyl butanoate

    SciTech Connect (OSTI)

    Dooley, S.; Curran, H.J.; Simmie, J.M.

    2008-04-15

    The autoignition of methyl butanoate has been studied at 1 and 4 atm in a shock tube over the temperature range 1250-1760 K at equivalence ratios of 1.5, 1.0, 0.5, and 0.25 at fuel concentrations of 1.0 and 1.5%. These measurements are complemented by autoignition data from a rapid compression machine over the temperature range 640-949 K at compressed gas pressures of 10, 20, and 40 atm and at varying equivalence ratios of 1.0, 0.5, and 0.33 using fuel concentrations of 1.59 and 3.13%. The autoignition of methyl butanoate is observed to follow Arrhenius-like temperature dependence over all conditions studied. These data, together with speciation data reported in the literature in a flow reactor, a jet-stirred reactor, and an opposed-flow diffusion flame, were used to produce a detailed chemical kinetic model. It was found that the model correctly simulated the effect of change in equivalence ratio, fuel fraction, and pressure for shock tube ignition delays. The agreement with rapid compression machine ignition delays is less accurate, although the qualitative agreement is reasonable. The model reproduces most speciation data with good accuracy. In addition, the important reaction pathways over each regime have been elucidated by both sensitivity and flux analyses. (author)

  10. Numerical model for the vacuum pyrolysis of scrap tires in batch reactors

    SciTech Connect (OSTI)

    Yang, J.; Tanguy, P.A.; Roy, C.

    1995-06-01

    A quantitative model for scrap tire pyrolysis in a batch scale reactor developed comprises the following basic phenomena: conduction inside tire particles; conduction, convection, and radiation between the feedstock particles or between the fluids and the particles; tire pyrolysis reaction; exothermicity and endothermicity caused by tire decomposition and volatilization; and the variation of the composition and the thermal properties of tire particles. This model was used to predict the transient temperature and density distributions in the bed of particles, the volatile product evolution rate, the mass change, the energy consumption during the pyrolysis process, and the pressure history in a tire pyrolysis reactor with a load of 1 kg. The model predictions agree well with independent experimental data.

  11. Synthesis of Numerical Methods for Modeling Wave Energy Converter-Point Absorbers: Preprint

    SciTech Connect (OSTI)

    Li, Y.; Yu, Y. H.

    2012-05-01

    During the past few decades, wave energy has received significant attention among all ocean energy formats. Industry has proposed hundreds of prototypes such as an oscillating water column, a point absorber, an overtopping system, and a bottom-hinged system. In particular, many researchers have focused on modeling the floating-point absorber as the technology to extract wave energy. Several modeling methods have been used such as the analytical method, the boundary-integral equation method, the Navier-Stokes equations method, and the empirical method. However, no standardized method has been decided. To assist the development of wave energy conversion technologies, this report reviews the methods for modeling the floating-point absorber.

  12. Modeling and numerical techniques for high-speed digital simulation of nuclear power plants

    SciTech Connect (OSTI)

    Wulff, W.; Cheng, H.S.; Mallen, A.N.

    1987-01-01

    Conventional computing methods are contrasted with newly developed high-speed and low-cost computing techniques for simulating normal and accidental transients in nuclear power plants. Six principles are formulated for cost-effective high-fidelity simulation with emphasis on modeling of transient two-phase flow coolant dynamics in nuclear reactors. Available computing architectures are characterized. It is shown that the combination of the newly developed modeling and computing principles with the use of existing special-purpose peripheral processors is capable of achieving low-cost and high-speed simulation with high-fidelity and outstanding user convenience, suitable for detailed reactor plant response analyses.

  13. Investigation of the effect of chemistry models on the numerical predictions of the supersonic combustion of hydrogen

    SciTech Connect (OSTI)

    Kumaran, K.; Babu, V.

    2009-04-15

    In this numerical study, the influence of chemistry models on the predictions of supersonic combustion in a model combustor is investigated. To this end, 3D, compressible, turbulent, reacting flow calculations with a detailed chemistry model (with 37 reactions and 9 species) and the Spalart-Allmaras turbulence model have been carried out. These results are compared with earlier results obtained using single step chemistry. Hydrogen is used as the fuel and three fuel injection schemes, namely, strut, staged (i.e., strut and wall) and wall injection, are considered to evaluate the impact of the chemistry models on the flow field predictions. Predictions of the mass fractions of major species, minor species, dimensionless stagnation temperature, dimensionless static pressure rise and thrust percentage along the combustor length are presented and discussed. Overall performance metrics such as mixing efficiency and combustion efficiency are used to draw inferences on the nature (whether mixing- or kinetic-controlled) and the completeness of the combustion process. The predicted values of the dimensionless wall static pressure are compared with experimental data reported in the literature. The calculations show that multi step chemistry predicts higher and more wide spread heat release than what is predicted by single step chemistry. In addition, it is also shown that multi step chemistry predicts intricate details of the combustion process such as the ignition distance and induction distance. (author)

  14. NUMERICAL MODEL OF PLASMA CONFINEMENT J. C. Sprott and E. J. Strait

    E-Print Network [OSTI]

    Sprott, Julien Clinton

    , a fast, simple, time-dependent, zero-dimensional computer model for plasmas confined in cylindrical chamber wall temperature (eV) B = average magnetic field strength (kG) B o = peak magnetic field strength) For the levitated toroidal oetupole, we take the values: T w = .025 eV a = 50 em L = 800 em Q = " 104 o S = 103

  15. Numerical modeling and experiments of creep crack growth under cyclic loading

    SciTech Connect (OSTI)

    Brust, F.W.

    1995-12-31

    This paper presents a summary of some recent studies of creep crack growth under history dependent load conditions. The effect of a proper constitutive law is illustrated. Moreover, the asymptotic fields are reconsidered under cyclic creep conditions. In addition, several experiments are modeled and the behavior of integral parameters is discussed.

  16. A numerical procedure to model and monitor CO2 sequestration in ...

    E-Print Network [OSTI]

    santos

    Sep 7, 2012 ... The model of the formation is based on the porosity and clay .... The porosity and dry bulk and shear modulus of the formation were obtained using a pore ... The viscosity, density and bulk modulus of CO2 needed for the flow ...

  17. Numerical modeling of spray cooling-assisted dermatologic laser surgery for treatment of port wine stains

    E-Print Network [OSTI]

    Aguilar, Guillermo

    . The objectives of this paper are: to improve the thermal modeling of skin undergoing CSC-assisted DLS for PWS that incorporate all the complexity of the problem are a valuable and fundamental research tool. Keywords: Spray Engineering, University of California, Riverside, CA 92521 bBeckman Laser Institute Medical Clinic, University

  18. A nanoscale numerical model of calcium silicate hydrate P.C. Fonseca a,

    E-Print Network [OSTI]

    Andrade, Jose

    to pre- dict the bulk properties of cement and concrete, such as shrinkage, creep, permeability and the properties of structural concrete are not fully under- stood. Models are becoming increasingly important, and cracking. C­S­H is responsible for much of the cohesive proper- ties in concrete but the chemical origin

  19. An XFEM Model for Carbon Sequestration Journal: International Journal for Numerical Methods in Engineering

    E-Print Network [OSTI]

    Gracie, Robert

    the temperatures and pressures are such that the CO2 exists in a supercritical state. The supercritical CO2 is less method (XFEM) model is presented to analyze the injection and sequestration of carbon dioxide (CO2 method (SUPG-FEM-FDM) to approximate the distribution of CO2 in the aquifer. Near well enrichment

  20. Malcolm Roberts: Research Statement My research interests are mathematical modelling, numerical analysis, and

    E-Print Network [OSTI]

    Roberts, Malcolm

    analysis, and high-performance computing. I have experience working in the areas of compu- tational fluid mechanics, subgrid models for turbulence, and flows in complex geometries. 1 Introduction Consider, which is the product of the characteristic length and velocity of the flow divided by the kinematic

  1. Distributed energy resources in practice: A case study analysis and validation of LBNL's customer adoption model

    SciTech Connect (OSTI)

    Bailey, Owen; Creighton, Charles; Firestone, Ryan; Marnay, Chris; Stadler, Michael

    2003-02-01

    This report describes a Berkeley Lab effort to model the economics and operation of small-scale (<500 kW) on-site electricity generators based on real-world installations at several example customer sites. This work builds upon the previous development of the Distributed Energy Resource Customer Adoption Model (DER-CAM), a tool designed to find the optimal combination of installed equipment, and idealized operating schedule, that would minimize the site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a historic test period, usually a recent year. This study offered the first opportunity to apply DER-CAM in a real-world setting and evaluate its modeling results. DER-CAM has three possible applications: first, it can be used to guide choices of equipment at specific sites, or provide general solutions for example sites and propose good choices for sites with similar circumstances; second, it can additionally provide the basis for the operations of installed on-site generation; and third, it can be used to assess the market potential of technologies by anticipating which kinds of customers might find various technologies attractive. A list of approximately 90 DER candidate sites was compiled and each site's DER characteristics and their willingness to volunteer information was assessed, producing detailed information on about 15 sites of which five sites were analyzed in depth. The five sites were not intended to provide a random sample, rather they were chosen to provide some diversity of business activity, geography, and technology. More importantly, they were chosen in the hope of finding examples of true business decisions made based on somewhat sophisticated analyses, and pilot or demonstration projects were avoided. Information on the benefits and pitfalls of implementing a DER system was also presented from an additional ten sites including agriculture, education, health care, airport, and manufacturing facilities.

  2. Development and Validation of Aggregated Models for Thermostatic Controlled Loads with Demand Response

    SciTech Connect (OSTI)

    Kalsi, Karanjit; Elizondo, Marcelo A.; Fuller, Jason C.; Lu, Shuai; Chassin, David P.

    2012-01-04

    Demand response is playing an increasingly important role in smart grid research and technologies being examined in recently undertaken demonstration projects. The behavior of load as it is affected by various load control strategies is important to understanding the degree to which different classes of end-use load can contribute to demand response programs at various times. This paper focuses on developing aggregated control models for a population of thermostatically controlled loads. The effects of demand response on the load population dynamics are investigated.

  3. A Complete Transport Validated Model on a Zeolite Membrane for Carbon Dioxide Permeance and Capture

    E-Print Network [OSTI]

    Gkanas, Evangelos I; Stubos, Athanasios K; Makridis, Sofoklis S

    2013-01-01

    The CO2 emissions from major industries cause serious global environment problems and their mitigation is urgently needed. The use of zeolite membranes is a very efficient way in order to capture CO2 from some flue gases. The dominant transport mechanism at low temperature andor high pressure is the diffusion through the membrane. This procedure can be divided in three steps: Adsorption of the molecules of the species in the surface of the membrane, then a driving force gives a path where the species follow inside the membrane and finally the species desorbed from the surface of the membrane. The current work is aimed at developing a simulation model for the CO2 transport through a zeolite membrane and estimate the diffusion phenomenon through a very thin membrane of 150 nm in a Wicke-Kallenbach cell. The cell is cylindrical in shape with diameter of 19 mm and consists of a retentate gas chamber, a permeate gas chamber which are separated by a cylindrical zeolite membrane. This apparatus have been modeled wit...

  4. CO{sub 2} adsorption: Experimental investigation with kinetics verification and CFD reactor model validation

    SciTech Connect (OSTI)

    Breault, Ronald W, [U.S. DOE; Huckaby, Ernest D. [U.S. DOE; Shadle, Lawrence J [U.S. DOE; Spenik, James L. [REM Engineering PLLC

    2013-01-01

    The National Energy Technology Laboratory is investigating a new process for CO{sub 2} capture from large sources such as utility power generation facilities as an alternative to liquid amine based absorption processes. Many, but not all of these advanced dry processes are based upon sorbents composed of supported polyamines. In this analysis, experiments have been conducted in a small facility at different temperatures and compared to CFD reactor predictions using kinetics obtained from TGA tests. This particular investigation compares the predicted performance and the experimental performance of one of these new class of sorbents in a fluidized bed reactor. In the experiment, the sorbent absorbs CO{sub 2} from simulated flue gas in a riser reactor, separates the carbonated particles from the de-carbonated flue gas in a cyclone and then regenerates the sorbent, creating a concentrated stream of pure CO{sub 2} for sequestration. In this work, experimental measurements of adsorption are compared to predictions from a 3-dimensional non-isothermal reacting multiphase flow model. The effects of the gas flow rate and reactor temperature are explored. It is shown that the time duration for CO{sub 2} adsorption decreased for an increase in the gas flow. The details of the experimental facility and the model as well as the comparative analysis between the data and the simulation results are discussed.

  5. Numerical study of three-dimensional PIC for the surface plasmon excitation based on Drude model

    E-Print Network [OSTI]

    Liu, La-Qun; Wang, Hui-Hui; Liu, Da-Gang

    2015-01-01

    This paper explores the time-domain equations of noble metals, in which Drude model is adopted to describe the dielectric constant, to implement three-dimensional particle-in-cell (PIC) simulations for the surface plasmon excitation with the finite-difference time-domain method (FDTD). A three-dimensional model for an electron bunch movement near the metal film is constructed, and particle-in-cell (PIC) simulations are carried out with various metal films of different thicknesses. The frequency of surface plasmon obtained from PIC simulation is agreed with that from theory. Furthermore, the surface plasmon wave properties of excitation and propagation with the metal film is summarized by PIC results.

  6. Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions 

    E-Print Network [OSTI]

    Gotika, Priyanka

    2012-02-14

    : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 73 ix LIST OF FIGURES FIGURE Page 1 Constitutive relation for Bingham-type uid. Force due to dash- pot cannot be written as a function of kinematic variables (that is, velocity of the mass). On the other hand, as shown in the gure, velocity... of constitutive relation between velocity and force due to dash-pot for a dash-pot governed by visco-elastic model. : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 9 5 A pictorial representation of constitutive relation between velocity...

  7. Modeling electrospinning process and a numerical scheme using Lattice Boltzmann method to simulate viscoelastic fluid flows 

    E-Print Network [OSTI]

    Karra, Satish

    2009-05-15

    [35] developed a stability analysis for the ax- isymmetric Rayleigh instability as well as the non-axisymmetric whipping instability in Newtonian fluids. According to them, the Rayleigh instability due to electrical forces is equivalent to the surface... for viscoelasticity between the beads. . . . . . . . 19 7 Typical result for the discrete particle model showing the bending loop in the jet. Top view shows that the envelope of the jet trajectory is a cone. The number of beads for this simulation N = 100 and non...

  8. Numerical Model for the Deformation of Nucleated Cells by Optical Stretchers

    E-Print Network [OSTI]

    Ihab Sraj; Joshua Francois; David W. M. Marr; Charles D. Eggleton

    2015-01-15

    In this paper, we seek to model the deformation of nucleated cells by single diode-laser bar optical stretchers. We employ a recently developed computational model, the Dynamic Ray-Tracing method, to determine the stress distribution induced by the applied optical forces on a capsule encapsulating a nucleus of different optical properties. These forces are shape dependent and can deform real non-rigid objects; thus resulting in a dynamically changing optical stress distribution with cell and nucleus deformation. Chinese hamster ovary cell is a common biological cell that is of interest to the biomedical community because of their use in recombinant protein therapeutics and is an example of a nucleated cell. To this end, we model chinese hamster ovary cells as two three-dimensional elastic capsules of variable inner capsule size immersed in a fluid where the hydrodynamic forces are calculated using the Immersed Boundary Method. Our results show that the presence of a nucleus has a major effect on the force distribution on the cell surface and the net deformation. Scattering and gradient forces are reported for different nucleus sizes and the effect of nucleus size on the cell deformation is discussed.

  9. Numerical Model for the Deformation of Nucleated Cells by Optical Stretchers

    E-Print Network [OSTI]

    Sraj, Ihab; Marr, David W M; Eggleton, Charles D

    2015-01-01

    In this paper, we seek to model the deformation of nucleated cells by single diode-laser bar optical stretchers. We employ a recently developed computational model, the Dynamic Ray-Tracing method, to determine the stress distribution induced by the applied optical forces on a capsule encapsulating a nucleus of different optical properties. These forces are shape dependent and can deform real non-rigid objects; thus resulting in a dynamically changing optical stress distribution with cell and nucleus deformation. Chinese hamster ovary cell is a common biological cell that is of interest to the biomedical community because of their use in recombinant protein therapeutics and is an example of a nucleated cell. To this end, we model chinese hamster ovary cells as two three-dimensional elastic capsules of variable inner capsule size immersed in a fluid where the hydrodynamic forces are calculated using the Immersed Boundary Method. Our results show that the presence of a nucleus has a major effect on the force dis...

  10. Modelling the high-energy emission from gamma-ray binaries using numerical relativistic hydrodynamics

    E-Print Network [OSTI]

    Dubus, Guillaume; Fromang, Sébastien

    2015-01-01

    Detailed modeling of the high-energy emission from gamma-ray binaries has been propounded as a path to pulsar wind physics. Fulfilling this ambition requires a coherent model of the flow and its emission in the region where the pulsar wind interacts with the stellar wind of its companion. We developed a code that follows the evolution and emission of electrons in the shocked pulsar wind based on inputs from a relativistic hydrodynamical simulation. The code is used to model the well-documented spectral energy distribution and orbital modulations from LS 5039. The pulsar wind is fully confined by a bow shock and a back shock. The particles are distributed into a narrow Maxwellian, emitting mostly GeV photons, and a power law radiating very efficiently over a broad energy range from X-rays to TeV gamma rays. Most of the emission arises from the apex of the bow shock. Doppler boosting shapes the X-ray and VHE lightcurves, constraining the system inclination to $i\\approx 35^{\\rm o}$. There is a tension between th...

  11. Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation

    SciTech Connect (OSTI)

    Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher

    2011-12-29

    The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.

  12. An improved neutral diffusion model and numerical solution of the two dimensional edge plasma fluid equations. Final report

    SciTech Connect (OSTI)

    Prinja, A.K.

    1998-09-01

    In this work, it has been shown that, for the given sets of parameters (transport coefficients), the Tangent-Predictor (TP) continuation method, which was used in the coarsest grid, works remarkably well. The problems in finding an initial guess that resides well within Newton`s method radius of convergence are alleviated by correcting the initial guess by the predictor step of the TP method. The TP method works well also in neutral gas puffing and impurity simulations. The neutral gas puffing simulation is performed by systematically increasing the fraction of puffing rate according to the TP method until it reaches a desired condition. Similarly, the impurity simulation characterized by using the fraction of impurity density as the continuation parameter, is carried out in line with the TP method. Both methods show, as expected, a better performance than the classical embedding (CE) method. The convergence criteria {epsilon} is set to be 10{sup {minus}9} based on the fact that lower value of {epsilon} does not alter the solution significantly. Correspondingly, the number of Newton`s iterations in the corrector step of the TP method decrease substantially, an extra point in terms of code speed. The success of the TP method enlarges the possibility of including other sets of parameters (operations and physics). With the availability of the converged coarsest grid solution, the next forward step to the multigrid cycle becomes possible. The multigrid method shows that the memory storage problems that plagued the application of Newton`s method on fine grids, are of no concern. An important result that needs to be noted here is the performance of the FFCD model. The FFCD model is relatively simple and is based on the overall results the model has shown to predict different divertor plasma parameters. The FFCD model treats exactly the implementation of the deep penetration of energetic neutrals emerging from the divertor plate. The resulting ionization profiles are relatively smooth as a consequence of the less localized recycling, leading to an improved convergence rate of the numerical algorithm. Peak plasma density is lower and the temperature correspondingly higher than those predicted by the standard diffusion model. It is believed that the FFCD model is more accurate. With both the TP continuation and multigrid methods, the author has demonstrated the robustness of these two methods. A mutually beneficial hybridization between the TP method and multigrid methods is clearly an alternative for edge plasma simulation. While the fundamental transport model considered in this work has ignored important physics such as drifts and currents, he has nevertheless demonstrated the versatility and robustness of the numerical scheme to handle such new physics. The application of gaseous-radiative divertor model in this work is just a beginning and up to this point numerically, the future is exciting.

  13. Mathematical and numerical models to achieve high speed with special-purpose parallel processors

    SciTech Connect (OSTI)

    Cheng, H.S.; Wulff, W.; Mallen, A.N.

    1986-07-01

    One simulation facility that has been developed is the BNL Plant Analyzer, currently set up for BWR plant simulations at up to seven times faster than real-time process speeds. The principal hardware components of the BNL Plant Analyzer are two units of special-purpose parallel processors, the AD10 of Applied Dynamics International and a PDP-11/34 host computer. The AD10 is specifically designed for time-critical system simulations, utilizing the modern parallel processing technology with pipeline architecture. The simulator employs advanced modeling techniques and efficient integration techniques in conjunction with the parallel processors to achieve high speed performance.

  14. Numerical modeling of boundary layer flow under shoaling and breaking waves 

    E-Print Network [OSTI]

    Pattipawaej, Olga Catherina

    1998-01-01

    velocities and shear stresses in the bottom boundary layer under breaking waves. The experiment wss conducted in the Precision Wave Tank located in the Ocean Engineering Laboratory at the University of Delaware. The flume was 33 m long, 0. 6 m wide, and 1... modeling of surf zone hydrodynamics. " Rep. No. CACR-95-97, Center for Applied Coastal Research, University Delaware, Newark, Delaware. Cox, D. T. , Kobayashi, N. , and Okayasu, A. (1996). "Bottom shear stress in the surf zone. " J. Geophys. Res. , 101(C...

  15. Numerical modeling of two-phase behavior in the PEFC gas diffusion layer

    SciTech Connect (OSTI)

    Mukherjee, Partha Pa223876 [Los Alamos National Laboratory; Kang, Qinjun [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Borup, Rod L [Los Alamos National Laboratory

    2009-01-01

    A critical performance limitation in the polymer electrolye fuel cell (PEFC) is attributed to the mass transport loss originating from suboptimal liquid water transport and flooding phenomena. Liquid water can block the porous pathways in the fibrous gas diffusion layer (GDL) and the catalyst layer (CL), thus hindering oxygen transport from the flow field to the electrochemically actives sites in the catalyst layer. In this paper, the study of the two phase behavior and the durability implications due to the wetting characteristics in the carbon paper GDL are presented using a pore-scale modeling framework.

  16. Dark matter, neutrino masses and high scale validity of an inert Higgs doublet model

    E-Print Network [OSTI]

    Nabarun Chakrabarty; Dilip Kumar Ghosh; Biswarup Mukhopadhyaya; Ipsita Saha

    2015-01-15

    We consider a two-Higgs doublet scenario containing three $SU(2)_L$ singlet heavy neutrinos with Majorana masses. The second scalar doublet as well as the neutrinos are odd under a $Z_2$ symmetry. This scenario not only generates Majorana masses for the light neutrinos radiatively but also makes the lighter of the neutral $Z_2$-odd scalars an eligible dark matter candidate, in addition to triggering leptogenesis at the scale of the heavy neutrino masses. Taking two representative values of this mass scale, we identify the allowed regions of the parameter space of the model, which are consistent with all dark matter constraints. At the same time, the running of quartic couplings in the scalar potential to high scales is studied, thus subjecting the regions consistent with dark matter constraints to further requirements of vacuum stability, perturbativity and unitarity. It is found that part of the parameter space is consistent with all of these requirements all the way up to the Planck scale, and also yields the correct signal strength in the diphoton channel for the scalar observed at the Large Hadron Collider.

  17. Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

    SciTech Connect (OSTI)

    Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France)

    2014-01-29

    In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  18. Numerical modelling of VLF radio wave propagation through earth-ionosphere waveguide and its application to sudden ionospheric disturbances

    E-Print Network [OSTI]

    Pal, Sujay

    2015-01-01

    In this thesis, we theoretically predict the normal characteristics of Very Low Frequency (3~30 kHz) radio wave propagation through Earth-ionosphere waveguide corresponding to normal behavior of the D-region ionosphere. We took the VLF narrow band data from the receivers of Indian Centre for Space Physics (ICSP) to validate our models. Detection of sudden ionospheric disturbances (SIDs) are common to all the measurements. We apply our theoretical models to infer the D-region characteristics and to reproduce the observed VLF signal behavior corresponding to such SIDs. We develop a code based on ray theory to simulate the diurnal behavior of VLF signals over short propagation paths (2000~3000 km). The diurnal variation from this code are comparable to the variation obtained from a more general Long Wave Propagation Capability (LWPC) code which is based on mode theory approach. We simulate the observational results obtained during the Total Solar Eclipse of July 22, 2009 in India. We also report and simulate a h...

  19. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    SciTech Connect (OSTI)

    Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France); Bradu, Benjamin [CERN, CH-1211 Genève 23 (Switzerland)

    2014-01-29

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  20. Fast Track Analysis of Shale Numerical Models A. Kalantari-Dahaghi ,SPE, S. Esmaili, SPE, West Virginia University, S.D. Mohaghegh, SPE, Intelligent Solution

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    SPE 162699 Fast Track Analysis of Shale Numerical Models A. Kalantari-Dahaghi ,SPE, S. Esmaili, SPE of SPE copyright. Abstract Latest advances in shale gas reservoir simulation and modeling have made it possible to optimize and enhance the production from organic rich shale gas reservoirs. Reservoir simulator

  1. Motivation Literature Trans. Network Models Relative Total Cost Indices Numerical Examples Summary A Relative Total Cost Index for the Evaluation of

    E-Print Network [OSTI]

    Nagurney, Anna

    A Relative Total Cost Index for the Evaluation of Transportation Network Robustness in the Presence Index #12;Motivation Literature Trans. Network Models Relative Total Cost Indices Numerical Examples, Qiang Qiang Relative Total Cost Index #12;Motivation Literature Trans. Network Models Relative Total

  2. ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS

    SciTech Connect (OSTI)

    Chiswell, S

    2009-01-11

    Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make consequence assessment more valuable during both routine operation as well as potential emergency situations. During 2008, the United States National Weather Service (NWS) radars implemented a significant upgrade which increased the real-time level II data resolution to 8 times their previous 'legacy' resolution, from 1 km range gate and 1.0 degree azimuthal resolution to 'super resolution' 250 m range gate and 0.5 degree azimuthal resolution (Fig 1). These radar observations provide reflectivity, velocity and returned power spectra measurements at a range of up to 300 km (460 km for reflectivity) at a frequency of 4-5 minutes and yield up to 13.5 million point observations per level in super-resolution mode. The migration of National Weather Service (NWS) WSR-88D radars to super resolution is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current operational mesoscale model domains utilize grid spacing several times larger than the legacy data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of super resolution reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution is investigated here to determine the impact of the improved data resolution on model predictions.

  3. Canyon Disposal Initiative - Numerical Modeling of Contaminant Transport from Grouted Residual Waste in the 221-U Facility (U Plant)

    SciTech Connect (OSTI)

    Rockhold, Mark L.; White, Mark D.; Freeman, Eugene J.

    2004-10-12

    This letter report documents initial numerical analyses conducted by PNNL to provide support for a feasibility study on decommissioning of the canyon buildings at Hanford. The 221-U facility is the first of the major canyon buildings to be decommissioned. The specific objective of this modeling effort was to provide estimates of potential rates of migration of residual contaminants out of the 221-U facility during the first 40 years after decommissioning. If minimal contaminant migration is predicted to occur from the facility during this time period, then the structure may be deemed to provide a level of groundwater protection that is essentially equivalent to the liner and leachate collection systems that are required at conventional landfills. The STOMP code was used to simulate transport of selected radionuclides out of a canyon building, representative of the 221-U facility after decommissioning, for a period of 40 years. Simulation results indicate that none of the selected radionuclides that were modeled migrated beyond the concrete structure of the facility during the 40-year period of interest. Jacques (2001) identified other potential contaminants in the 221-U facility that were not modeled, however, including kerosene, phenol, and various metals. Modeling of these contaminants was beyond the scope of this preliminary effort due to increased complexity. Simulation results indicate that contaminant release from the canyon buildings will be diffusion controlled at early times. Advection is expected to become much more important at later times, after contaminants have diffused out of the facility and into the surrounding soil environment. After contaminants have diffused out of the facility, surface infiltration covers will become very important for mitigating further transport of contaminants in the underlying vadose zone and groundwater.

  4. Model Verification and Validation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGEMission Mission Missionof EnergyJennings= a Judicial Science

  5. Methyl Formate Oxidation: Speciation Data, Laminar Burning Velocities, Ignition Delay Times and a Validated Chemical Kinetic Model

    SciTech Connect (OSTI)

    Dooley, S.; Burke, M. P.; Chaos, M.; Stein, Y.; Dryer, F. L.; Zhukov, V. P.; Finch, O.; Simmie, J. M.; Curran, H. J.

    2010-07-16

    The oxidation of methyl formate (CH{sub 3}OCHO) has been studied in three experimental environments over a range of applied combustion relevant conditions: 1. A variable-pressure flow reactor has been used to quantify reactant, major intermediate and product species as a function of residence time at 3 atm and 0.5% fuel concentration for oxygen/fuel stoichiometries of 0.5, 1.0, and 1.5 at 900 K, and for pyrolysis at 975 K. 2. Shock tube ignition delays have been determined for CH{sub 3}OCHO/O{sub 2}/Ar mixtures at pressures of ? 2.7, 5.4, and 9.2 atm and temperatures of 1275–1935 K for mixture compositions of 0.5% fuel (at equivalence ratios of 1.0, 2.0, and 0.5) and 2.5% fuel (at an equivalence ratio of 1.0). 3. Laminar burning velocities of outwardly propagating spherical CH{sub 3}OCHO/air flames have been determined for stoichiometries ranging from 0.8–1.6, at atmospheric pressure using a pressure-release-type high-pressure chamber. A detailed chemical kinetic model has been constructed, validated against, and used to interpret these experimental data. The kinetic model shows that methyl formate oxidation proceeds through concerted elimination reactions, principally forming methanol and carbon monoxide as well as through bimolecular hydrogen abstraction reactions. The relative importance of elimination versus abstraction was found to depend on the particular environment. In general, methyl formate is consumed exclusively through molecular decomposition in shock tube environments, while at flow reactor and freely propagating premixed flame conditions, there is significant competition between hydrogen abstraction and concerted elimination channels. It is suspected that in diffusion flame configurations the elimination channels contribute more significantly than in premixed environments.

  6. Gas release during salt-well pumping: Model predictions and laboratory validation studies for soluble and insoluble gases

    SciTech Connect (OSTI)

    Peurrung, L.M.; Caley, S.M.; Gauglitz, P.A.

    1997-08-01

    The Hanford Site has 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. Of these, 67 are known or suspected to have leaked liquid from the tanks into the surrounding soil. Salt-well pumping, or interim stabilization, is a well-established operation for removing drainable interstitial liquid from SSTs. The overall objective of this ongoing study is to develop a quantitative understanding of the release rates and cumulative releases of flammable gases from SSTs as a result of salt-well pumping. The current study is an extension of the previous work reported by Peurrung et al. (1996). The first objective of this current study was to conduct laboratory experiments to quantify the release of soluble and insoluble gases. The second was to determine experimentally the role of characteristic waste heterogeneities on the gas release rates. The third objective was to evaluate and validate the computer model STOMP (Subsurface Transport over Multiple Phases) used by Peurrung et al. (1996) to predict the release of both soluble (typically ammonia) and insoluble gases (typically hydrogen) during and after salt-well pumping. The fourth and final objective of the current study was to predict the gas release behavior for a range of typical tank conditions and actual tank geometry. In these models, the authors seek to include all the pertinent salt-well pumping operational parameters and a realistic range of physical properties of the SST wastes. For predicting actual tank behavior, two-dimensional (2-D) simulations were performed with a representative 2-D tank geometry.

  7. Calibration and Validation of a FAST Floating Wind Turbine Model of the DeepCwind Scaled Tension-Leg Platform: Preprint

    SciTech Connect (OSTI)

    Stewart, G.; Lackner, M.; Robertson, A.; Jonkman, J.; Goupee, A.

    2012-05-01

    With the intent of improving simulation tools, a 1/50th-scale floating wind turbine atop a TLP was designed based on Froude scaling by the University of Maine under the DeepCwind Consortium. This platform was extensively tested in a wave basin at MARIN to provide data to calibrate and validate a full-scale simulation model. The data gathered include measurements from static load tests and free-decay tests, as well as a suite of tests with wind and wave forcing. A full-scale FAST model of the turbine-TLP system was created for comparison to the results of the tests. Analysis was conducted to validate FAST for modeling the dynamics of this floating system through comparison of FAST simulation results to wave tank measurements. First, a full-scale FAST model of the as-tested scaled configuration of the system was constructed, and this model was then calibrated through comparison to the static load, free-decay, regular wave only, and wind-only tests. Next, the calibrated FAST model was compared to the combined wind and wave tests to validate the coupled hydrodynamic and aerodynamic predictive performance. Limitations of both FAST and the data gathered from the tests are discussed.

  8. Vehicle Technologies Office Merit Review 2015: Validation of Material Models for Crash Simulation of Automotive Carbon Fiber Composite Structures (VMM)

    Broader source: Energy.gov [DOE]

    Presentation given by Ford Motor Company at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about validation of material...

  9. Use of international data sets to evaluate and validate pathway assessment models applicable to exposure and dose reconstruction at DOE facilities. Progress report, March--May 1994

    SciTech Connect (OSTI)

    Anspaugh, L.R.; Hendrickson, S.M.; Hoffman, F.O.

    1994-06-01

    The project described in this report was the result of a Memorandum of Cooperation between the US and the former-USSR following the accident at the Chernobyl Nuclear Power Plant Unit 4. A joint program was established to improve the safety of nuclear power plants and to understand the implications of environmental releases. The task of Working Group 7 was ``to develop jointly methods to project rapidly the health effects of any future nuclear reactor accident.`` The current objective of this project is to evaluate and validate pathway-assessment models applicable to exposure and dose reconstruction at DOE facilities through use of international data sets. This project incorporates data used for the prediction of radionuclide transfer through agricultural and aquatic systems to humans. It also includes participation in two multinational studies, BIOMOVS (Biospheric Model Validation Study) with the Swedish National Institute for Radiation Protection and VAMP (Validation of Model Predictions) with the International Atomic Energy Agency, that address testing the performance of models of radionuclide transport through foodchains. In the future, this project will be considered separately from the Chernobyl Studies Project and the essential activities of former Task 7.1D will be folded within the broader umbrella of the BIOMOVS and VAMP projects. The Working Group Leader of Task 7.1D will continue to provide oversight for this project.

  10. IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS, VOL. 17, NO. 4, APRIL 1998 305 Numerically Stable Green Function for Modeling and

    E-Print Network [OSTI]

    California at Berkeley, University of

    IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS, VOL. 17, NO. 4, APRIL 1998 305 Numerically Stable Green Function for Modeling and Analysis of Substrate Coupling. Meyer, Fellow, IEEE Abstract-- The Green function over a multilayer substrate is derived by solving

  11. Numerical analysis of a locking-free mixed finite element method for a bending moment formulation of Reissner-Mindlin plate model

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    ´on, Chile. This paper deals with the approximation of the bending of a clamped plate modeled by ReissnerNumerical analysis of a locking-free mixed finite element method for a bending moment formulation the thickness t is small. Here, we propose a new mixed formulation in terms of the bending moments, shear stress

  12. An analytical and numerical model to determine stresses in a Rock Melt Drill produced glass liner for potential use on Mars 

    E-Print Network [OSTI]

    McConnell, Joshua B

    2000-01-01

    A numerical and analytical model was constructed to determine the resultant stress state imposed on a Rock Melt Drill produced liner. The purpose of this study was to determine if the liner produced would possess the strength required to prevent a...

  13. SANSMIC Validation.

    SciTech Connect (OSTI)

    Weber, Paula D.; Rudeen, David Keith; Lord, David

    2014-08-01

    SANSMIC is solution mining software that was developed and utilized by SNL in its role as geotechnical advisor to the US DOE SPR for planning purposes. Three SANSMIC leach modes - withdrawal, direct, and reverse leach - have been revalidated with multiple test cases for each mode. The withdrawal mode was validated using high quality data from recent leach activity while the direct and reverse modes utilized data from historical cavern completion reports. Withdrawal results compared very well with observed data, including the location and size of shelves due to string breaks with relative leached volume differences ranging from 6 - 10% and relative radius differences from 1.5 - 3%. Profile comparisons for the direct mode were very good with relative leached volume differences ranging from 6 - 12% and relative radius differences from 5 - 7%. First, second, and third reverse configurations were simulated in order to validate SANSMIC over a range of relative hanging string and OBI locations. The first-reverse was simulated reasonably well with relative leached volume differences ranging from 1 - 9% and relative radius differences from 5 - 12%. The second-reverse mode showed the largest discrepancies in leach profile. Leached volume differences ranged from 8 - 12% and relative radius differences from 1 - 10%. In the third-reverse, relative leached volume differences ranged from 10 - 13% and relative radius differences were ~4 %. Comparisons to historical reports were quite good, indicating that SANSMIC is essentially the same as documented and validated in the early 1980's.

  14. Numerical Transform Inversion to Analyze Teletraffic Models Gagan L. Choudhury, a David M. Lucantoni a and Ward Whitt b

    E-Print Network [OSTI]

    Whitt, Ward

    . Lucantoni a and Ward Whitt b a AT&T Bell Laboratories, Holmdel, NJ 07733­3030, USA b AT&T Bell Laboratories, Murray Hill, NJ 07974­0636, USA We describe recently developed algorithms for numerically inverting

  15. Numerical failure analysis of a stretch-bending test on dual-phase steel sheets using a phenomenological fracture model

    E-Print Network [OSTI]

    Luo, Meng

    Advanced High Strength Steels (AHSS) are increasingly used in automotive industry due to their superior strength and substantial weight advantage. However, their compromised ductility gives rise to numerous manufacturing ...

  16. American Institute of Aeronautics and Astronautics Wind Tunnel Validation of a CFD-Based Aero-Optics Model

    E-Print Network [OSTI]

    Gordeyev, Stanislav

    American Institute of Aeronautics and Astronautics 1 Wind Tunnel Validation of a CFD-Based Aero Air Force Academy, Colorado Spring, CO Abstract: A computational fluid dynamics (CFD)-based aero LATFORMS at high subsonic Mach numbers introduce aero-optic disturbances caused when free shear layers

  17. Verification and Validation Strategy for LWRS Tools

    SciTech Connect (OSTI)

    Carl M. Stoots; Richard R. Schultz; Hans D. Gougar; Thomas K Larson; Michael Corradini; Laura Swiler; David Pointer; Jess Gehin

    2012-09-01

    One intension of the Department of Energy (DOE) Light Water Reactor Sustainability (LWRS) program is to create advanced computational tools for safety assessment that enable more accurate representation of a nuclear power plant safety margin. These tools are to be used to study the unique issues posed by lifetime extension and relicensing of the existing operating fleet of nuclear power plants well beyond their first license extension period. The extent to which new computational models / codes such as RELAP-7 can be used for reactor licensing / relicensing activities depends mainly upon the thoroughness with which they have been verified and validated (V&V). This document outlines the LWRS program strategy by which RELAP-7 code V&V planning is to be accomplished. From the perspective of developing and applying thermal-hydraulic and reactivity-specific models to reactor systems, the US Nuclear Regulatory Commission (NRC) Regulatory Guide 1.203 gives key guidance to numeric model developers and those tasked with the validation of numeric models. By creating Regulatory Guide 1.203 the NRC defined a framework for development, assessment, and approval of transient and accident analysis methods. As a result, this methodology is very relevant and is recommended as the path forward for RELAP-7 V&V. However, the unique issues posed by lifetime extension will require considerations in addition to those addressed in Regulatory Guide 1.203. Some of these include prioritization of which plants / designs should be studied first, coupling modern supporting experiments to the stringent needs of new high fidelity models / codes, and scaling of aging effects.

  18. Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models

    SciTech Connect (OSTI)

    Houze, Jr., Robert A.

    2013-11-13

    We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. 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 observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.

  19. Positive field-cooled dc susceptibility in granular superconductors interpreted through numerical simulations on a simple Josephson-junction-array model

    SciTech Connect (OSTI)

    Auletta, C.; Raiconi, G.; De Luca, R.; Pace, S.

    1995-05-01

    We have performed numerical simulations of a field-cooled dc susceptibility experiment carried out for granular superconductors by modeling these systems with a simple Josephson-junction array proposed by the authors. By this analysis the temperature dependence of the positive field-cooled susceptibility at very low values of the applied magnetic field, observed by Braunisch {ital et} {ital al}. [Phys. Rev. Lett. 68, 1908 (1992)] for some ceramic superonductors, has been reproduced and interpreted.

  20. MARMOT Validation

    Broader source: Energy.gov [DOE]

    The composition-dependent mobility in the formulism of the phase-field modeling is implemented into the MARMOT phase-field algorithm.