Atmospheric radiative transfer parametrization for solar energy yield calculations on buildings
Wagner, Jochen E
2015-01-01T23:59:59.000Z
In this paper the practical approach to evaluate the incoming solar radiation on buildings based on atmospheric composition and cloud cover is presented. The effects of absorption and scattering due to atmospheric composition is taken into account to calculate, using radiative transfer models, the net incoming solar radiation at surface level. A specific validation of the Alpine Region in Europe is presented with a special focus on the region of South Tyrol.
Radiative component and combined heat transfer in the thermal calculation of finned tube banks
Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering
1999-01-01T23:59:59.000Z
For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.
Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application
New York at Stoney Brook, State University of
the parallelization of the radiative heat transfer model introduced by Naraghi and Nunes of Manhattan College [8
The effect of the number of wavebands used in spectral radiation heat transfer calculations
Chang, S. L.; Golchert, B.; Petrick, M.
2000-05-09T23:59:59.000Z
A spectral radiation heat transfer model that conserves emitted and absorbed energy has been developed and used to model the combustion space of an industrial glass furnace. This comprehensive radiation heat transfer model coupled with a computational fluid dynamics (CFD) code was used to investigate the effect of spectral dependencies on the computed results. The results of this work clearly indicate the need for a spectral approach as opposed to a gray body approach since the gray body approach (one waveband) severely underestimates the energy emitted via radiation.
HELIOS-K: An Ultrafast, Open-source Opacity Calculator for Radiative Transfer
Grimm, Simon L
2015-01-01T23:59:59.000Z
We present an ultrafast opacity calculator for application to exoplanetary atmospheres, which we name HELIOS-K. It takes a line list as an input, computes the shape of each spectral line (e.g., a Voigt profile) and provides an option for grouping an enormous number of lines into a manageable number of bins. We implement a combination of Algorithm 916 and Gauss-Hermite quadrature to compute the Voigt profile, write the code in CUDA and optimise the computation for graphics processing units (GPUs). We use the k-distribution method to reduce $\\sim 10^5$ to $10^8$ lines to $\\sim 10$ to $10^4$ wavenumber bins, which may then be used for radiative transfer, atmospheric retrieval and general circulation models. We demonstrate that the resampling of the k-distribution function, within each bin, is an insignificant source of error across a broad range of wavenumbers and column masses. By contrast, the choice of line-wing cutoff for the Voigt profile is a significant source of error and affects the value of the compute...
Solar radiation intensity calculations
Levine, Randolph Steven
1978-01-01T23:59:59.000Z
SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Submitted to the Graduate College of Texas A&M University in partia'l fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject...: Physics SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Approved as to style and content by: (Chairman of Committee) (Member) (Member) ( member) (Head of Department) December 1978 f219 037 ABSTRACT Solar Radiation...
General Relativistic Radiative Transfer
S. Knop; P. H. Hauschildt; E. Baron
2006-11-30T23:59:59.000Z
We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz that allows to resolve spectral lines throughout the atmosphere. The used numerical solution is an operator splitting (OS) technique that uses a characteristic formal solution. The bending of photon paths and the wavelength shifts due to the effects of GR are fully taken into account, as is the treatment of image generation in a curved spacetime. We describe the algorithm we use and demonstrate the effects of GR on the radiative transport of a two level atom line in a neutron star like atmosphere for various combinations of continuous and line scattering coefficients. In addition, we present grey continuum models and discuss the effects of different scattering albedos on the emergent spectra and the determination of effective temperatures and radii of neutron star atmospheres.
Three Dimensional Radiative Transfer
Tom Abel
2000-05-09T23:59:59.000Z
Radiative Transfer (RT) effects play a crucial role in the thermal history of the intergalactic medium. Here I discuss recent advances in the development of numerical methods that introduce RT to cosmological hydrodynamics. These methods can also readily be applied to time dependent problems on interstellar and galactic scales.
Radiative heat transfer in porous uranium dioxide
Hayes, S.L. [Texas A and M Univ., College Station, TX (United States)] [Texas A and M Univ., College Station, TX (United States)
1992-12-01T23:59:59.000Z
Due to low thermal conductivity and high emissivity of UO{sub 2}, it has been suggested that radiative heat transfer may play a significant role in heat transfer through pores of UO{sub 2} fuel. This possibility was computationally investigated and contribution of radiative heat transfer within pores to overall heat transport in porous UO{sub 2} quantified. A repeating unit cell was developed to model approximately a porous UO{sub 2} fuel system, and the heat transfer through unit cells representing a wide variety of fuel conditions was calculated using a finite element computer program. Conduction through solid fuel matrix as wekk as pore gas, and radiative exchange at pore surface was incorporated. A variety of pore compositions were investigated: porosity, pore size, shape and orientation, temperature, and temperature gradient. Calculations were made in which pore surface radiation was both modeled and neglected. The difference between yielding the integral contribution of radiative heat transfer mechanism to overall heat transport. Results indicate that radiative component of heat transfer within pores is small for conditions representative of light water reactor fuel, typically less than 1% of total heat transport. It is much larger, however, for conditions present in liquid metal fast breeder reactor fuel; during restructuring of this fuel type early in life, the radiative heat transfer mode was shown to contribute as much as 10-20% of total heat transport in hottest regions of fuel.
Solar radiation intensity calculations
Levine, Randolph Steven
1978-01-01T23:59:59.000Z
, radiation per unit area per unit time, on a flat-plate collector is given by: I = I cos B (2. 1a) where I is the solar constant. insolation received at one astro- nomical unit from the sun. Since clear sky conditions are assumed I o w i 1 1 b e a.... INSOLATION EQUATIONS TABLE OF CONTENTS Page III. RESULTS AND CONCLUSIONS REFERENCES APPENDIX VITA 25 47 48 52 Vi LIST OF TABLES TABLE I. Optimal Inclination for Ap=O, No Checks for Ip &0 and a Time Independent Solar Constant. II. Optimal...
Siewert, Charles E.
subject to Fresnel boundary and interface conditions R.D.M. Garcia a,Ã, C.E. Siewert b a Instituto de: Radiative transfer Nascent delta function Fresnel conditions Discrete-ordinates method a b s t r a c in a plane-parallel, multi-layer medium subject to Fresnel boundary and interface conditions. As a result
Radiative transfer in molecular lines
A. Asensio Ramos; J. Trujillo Bueno; J. Cernicharo
2001-02-15T23:59:59.000Z
The highly convergent iterative methods developed by Trujillo Bueno and Fabiani Bendicho (1995) for radiative transfer (RT) applications are generalized to spherical symmetry with velocity fields. These RT methods are based on Jacobi, Gauss-Seidel (GS), and SOR iteration and they form the basis of a new NLTE multilevel transfer code for atomic and molecular lines. The benchmark tests carried out so far are presented and discussed. The main aim is to develop a number of powerful RT tools for the theoretical interpretation of molecular spectra.
Three-dimensional Radiative Transfer with Multilevel Atoms
P. Fabiani Bendicho; J. Trujillo Bueno
2007-10-29T23:59:59.000Z
The efficient numerical solution of Non-LTE multilevel transfer problems requires the combination of highly convergent iterative schemes with fast and accurate formal solution methods of the radiative transfer (RT) equation. This contribution begins presenting a method for the formal solution of the RT equation in three-dimensional (3D) media with horizontal periodic boundary conditions. This formal solver is suitable for both, unpolarized and polarized 3D radiative transfer and it can be easily combined with the iterative schemes for solving non-LTE multilevel transfer problems that we have developed over the last few years. We demonstrate this by showing some schematic 3D multilevel calculations that illustrate the physical effects of horizontal radiative transfer. These Non-LTE calculations have been carried out with our code MUGA 3D, a 3D multilevel Non-LTE code based on the Gauss-Seidel iterative scheme that Trujillo Bueno and Fabiani Bendicho (1995) developed for RT applications.
Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass
Kitamura, Rei; Pilon, Laurent
2009-01-01T23:59:59.000Z
Kaviany and B.P. Singh, “Radiative heat transfer in porousmedia”, Advances in Heat Transfer, vol. 23, no. 23, pp. 133–Thermal radiation heat transfer, Hemisphere Publishing Co. ,
Radiative heat transfer between dielectric bodies
Svend-Age Biehs
2011-03-16T23:59:59.000Z
The recent development of a scanning thermal microscope (SThM) has led to measurements of radiative heat transfer between a heated sensor and a cooled sample down to the nanometer range. This allows for comparision of the known theoretical description of radiative heat transfer, which is based on fluctuating electrodynamics, with experiment. The theory itself is a macroscopic theory, which can be expected to break down at distances much smaller than 10-8m. Against this background it seems to be reasonable to revisit the known macroscopic theory of fluctuating electrodynamics and of radiative heat transfer.
Radiative transfer for the FIRST era
J. Trujillo Bueno
2001-02-15T23:59:59.000Z
This paper presents a brief overview of some recent advances in numerical radiative transfer, which may help the molecular astrophysics community to achieve new breakthroughs in the interpretation of spectro-(polarimetric) observations.
Radiative Heat Transfer between Neighboring Particles
Alejandro Manjavacas; F. Javier Garcia de Abajo
2012-01-26T23:59:59.000Z
The near-field interaction between two neighboring particles is known to produce enhanced radiative heat transfer. We advance in the understanding of this phenomenon by including the full electromagnetic particle response, heat exchange with the environment, and important radiative corrections both in the distance dependence of the fields and in the particle absorption coefficients. We find that crossed terms of electric and magnetic interactions dominate the transfer rate between gold and SiC particles, whereas radiative corrections reduce it by several orders of magnitude even at small separations. Radiation away from the dimer can be strongly suppressed or enhanced at low and high temperatures, respectively. These effects must be taken into account for an accurate description of radiative heat transfer in nanostructured environments.
Fresnel Effect in Radiation Transfer in Biological Tissues Kyunghan Kim and Zhixiong Guo*
Guo, Zhixiong "James"
Fresnel Effect in Radiation Transfer in Biological Tissues Kyunghan Kim and Zhixiong Guo* MAE Method (DOM) to incorporate Fresnel's boundary in laser radiation transport in biological tissues is calculated by the use of Snell's law and Fresnel's equation. The radiation fields, including the radiative
accelerated radiative transfer: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
influence of particle shape on the radiative forcing caused by a cloud composed of small ice 123 Journal of Quantitative Spectroscopy & Radiative Transfer 101 (2006) 556...
Agriculture-related radiation dose calculations
Furr, J.M.; Mayberry, J.J.; Waite, D.A.
1987-10-01T23:59:59.000Z
Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs.
RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda
RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda A. Kersch 1 W. Morokoff 2 A accuracy modeling of the radiative heat transfer from the heater to the wafer. Figure 1 shows the draft Carlo simulation is often used to solve radiative transfer problems where complex physical phenomena
RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS
RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS A. Kersch1 W. Moroko2 A. Schuster1 1Siemens of Quasi-Monte Carlo to this problem. 1.1 Radiative Heat Transfer Reactors In the manufacturing of the problems which can be solved by such a simulation is high accuracy modeling of the radiative heat transfer
Heat Transfer Calculations for a Fixed CST Bed Column
Lee, S.Y.
2001-03-28T23:59:59.000Z
In support of the crystalline silicotitanate (CST) ion exchange project of High-Level Waste (HLW) Process Engineering, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the CST column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. The modeling and calculations were performed using a computational heat transfer approach.
Calculating reactor transfer functions by Pade approximation via Lanczos algorithm
PÃ¡zsit, Imre
Calculating reactor transfer functions by PadeÃ? approximation via Lanczos algorithm Zhifeng Kuang a function of a reactor, i.e. the neutron noise induced by a localised perturbation is calculated in one, *,1 , Imre PaÃ? zsit a , Axel Ruhe b a Department of Reactor Physics, Chalmers University of Technology
Radiative heat transfer in anisotropic many-body systems: Tuning and enhancement
Nikbakht, Moladad, E-mail: mnik@znu.ac.ir [Department of Physics, Faculty of Sciences, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of)
2014-09-07T23:59:59.000Z
A general formalism for calculating the radiative heat transfer in many body systems with anisotropic component is presented. Our scheme extends the theory of radiative heat transfer in isotropic many body systems to anisotropic cases. In addition, the radiative heating of the particles by the thermal bath is taken into account in our formula. It is shown that the radiative heat exchange (HE) between anisotropic particles and their radiative cooling/heating (RCH) could be enhanced several order of magnitude than that of isotropic particles. Furthermore, we demonstrate that both the HE and RCH can be tuned dramatically by particles relative orientation in many body systems.
Chen, Y.; Li, X.; Zhang, Q.; Spitler, J.; Fisher, D.
2006-01-01T23:59:59.000Z
Conduction transfer functions (CTFs) are widely used to calculate conduction heat transfer in building cooling load and energy calculations. They can conveniently fit into any load and energy calculation techniques to perform conduction calculations...
Investigation of spectral radiation heat transfer and NO{sub x} emission in a glass furnace
Golchert, B.; Zhou, C. Q.; Chang, S. L.; Petrick, M.
2000-08-02T23:59:59.000Z
A comprehensive radiation heat transfer model and a reduced NOx kinetics model were coupled with a computational fluid dynamics (CFD) code and then used to investigate the radiation heat transfer, pollutant formation and flow characteristics in a glass furnace. The radiation model solves the spectral radiative transport equation in the combustion space of emitting and absorbing media, i.e., CO{sub 2}, H{sub 2}O, and soot and emission/reflection from the furnace crown. The advanced numerical scheme for calculating the radiation heat transfer is extremely effective in conserving energy between radiation emission and absorption. A parametric study was conducted to investigate the impact of operating conditions on the furnace performance with emphasis on the investigation into the formation of NOx.
Fedkiw, Peter
2011-01-01T23:59:59.000Z
Calculations for the Asymptotic, Diffusion Dominated Mass-Transfer Coefficient in Packed Bed Reactors
Chen, Y.; Li, X.; Zhang, Q.; Spitler, J.; Fisher, D.
2006-01-01T23:59:59.000Z
USA lxq9031@yahoo.com.cn Abstract: Conduction transfer functions (CTFs) are widely used to calculate conduction heat transfer in building cooling load and energy calculations. They can conveniently fit into any load and energy calculation...
Small distance expansion for radiative heat transfer between curved objects
Golyk, Vladyslav A.
We develop a small distance expansion for the radiative heat transfer between gently curved objects, in terms of the ratio of distance to radius of curvature. A gradient expansion allows us to go beyond the lowest-order ...
Stefan Jordan; Holger Schmidt
2003-02-04T23:59:59.000Z
We compare four different methods to calculate radiative transfer through a magnetized stellar atmosphere, and apply them to the case of magnetic white dwarfs. All methods are numerically stable enough to allow determination of the magnetic field structure, but distinctions between faster, simplifying, methods, and elaborate, but more CPU-time consuming, methods, can be made.
Re ectance comparison between SCIAMACHY and a radiative transfer code in the UV
Tilstra, Gijsbert
Kon i nk l i j k Neder l ands Meteoro l og i sch Inst i tuut Re#29;ectance comparison between SCIAMACHY and a radiative transfer code in the UV L.G. Tilstra, G. van Soest, M. de Graaf, J.R. Acarreta, P#21;2400 nm. We compare its re#29;ectance mea- surements in the UV with calculations by a polarised radiative
COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS
Tanner, Joel D.; Basu, Sarbani; Demarque, Pierre [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)
2012-11-10T23:59:59.000Z
We examine the effect of different radiative transfer schemes on the properties of three-dimensional (3D) simulations of near-surface stellar convection in the superadiabatic layer, where energy transport transitions from fully convective to fully radiative. We employ two radiative transfer schemes that fundamentally differ in the way they cover the 3D domain. The first solver approximates domain coverage with moments, while the second solver samples the 3D domain with ray integrations. By comparing simulations that differ only in their respective radiative transfer methods, we are able to isolate the effect that radiative efficiency has on the structure of the superadiabatic layer. We find the simulations to be in good general agreement, but they show distinct differences in the thermal structure in the superadiabatic layer and atmosphere.
Enhanced radiative heat transfer between nanostructured gold plates
R. Guérout; J. Lussange; F. S. S. Rosa; J. -P. Hugonin; D. A. R. Dalvit; J. -J. Greffet; A. Lambrecht; S. Reynaud
2012-03-07T23:59:59.000Z
We compute the radiative heat transfer between nanostructured gold plates in the framework of the scattering theory. We predict an enhancement of the heat transfer as we increase the depth of the corrugations while keeping the distance of closest approach fixed. We interpret this effect in terms of the evolution of plasmonic and guided modes as a function of the grating's geometry.
Modelling of Radiative Transfer in Light Sources
Eindhoven, Technische Universiteit
. . . . . . . . . . . . . . . 30 2.5.3 Temperature distribution . . . . . . . . . . . . . . . . . . . . . . . . . 32 2-X radiative transition that is responsible for the sulfur lamp's bright sun-like spectrum #12;Contents 1
Adaptive Ray Tracing for Radiative Transfer around Point Sources
Tom Abel; Benjamin D. Wandelt
2001-11-01T23:59:59.000Z
We describe a novel adaptive ray tracing scheme to solve the equation of radiative transfer around point sources in hydrodynamical simulations. The angular resolution adapts to the local hydrodynamical resolution and hence is of use for adaptive meshes as well as adaptive smooth particle hydrodynamical simulations. Recursive creation of rays ensures ease of implementation. The multiple radial integrations needed to solve the time dependent radiative transfer are sped up significantly using a quad-tree once the rays are cast. Simplifications advantageous for methods with one radiation source are briefly discussed. The suggested method is easily generalized to speed up Monte Carlo radiative transfer techniques. In summary a nearly optimal use of long characteristics is presented and aspects of its implementation and comparison to other methods are given.
Heat transfer including radiation and slag particles evolution in MHD channel-I
Im, K.H.; Ahluwalia, R.K.
1980-01-01T23:59:59.000Z
Accurate estimates of convective and radiative heat transfer in the magnetohydrodynamic channel are provided. Calculations performed for a base load-size channel indicate that heat transfer by gas radiation almost equals that by convection for smooth walls, and amounts to 70% as much as the convective heat transfer for rough walls. Carbon dioxide, water vapor, and potassium atoms are the principal participating gases. The evolution of slag particles by homogeneous nucleation and condensation is also investigated. The particle-size spectrum so computed is later utilized to analyze the radiation enhancement by slag particles in the MHD diffuser. The impact of the slag particle spectrum on the selection of a workable and design of an efficient seed collection system is discussed.
Numerical methods for multidimensional radiative transfer
radiation plays a key role in various scientific applications, such as combustion physics, thermonuclear fusion and astrophysics. The equa- tion describing the transport of photons or neutrons through a medium
Optical Properties of Saharan Dust and Asian Dust: Application to Radiative Transfer Simulations
Fang, Guangyang
2012-07-16T23:59:59.000Z
properties for radiative transfer simulations. Using a Rapid Radiative Transfer Model (RRTM), the radiative forcing of mineral dust was computed at both the top of the atmosphere and the surface. By analyzing samples from various in-situ measurements, we...
D0 Solenoid Upgrade Project: Chimney LN2 Radiation Shield Attachment Area Calculation
Rucinski, R.; /Fermilab
1993-05-26T23:59:59.000Z
A short calculation was done to check the attachment method of the radiation shield to it's LN2 cooling tubes. The case considered was only for the obround chimney section. The proposed attachment method was to use 1/8-inch plug welds spaced every 5-inch along the length of the shield. The calculations were done conservatively for 6-inch spacing between plug welds. The criteria used was that the LN2 shield warmest temperature be less than 2 K above the temperature of the LN2 fluid. Using a very conservative heat transfer model. the calculations predict that the warmest temperature on the radiation shield will be < 1.4 K warmer than the LN2 fluid temperature.
Debris Disk Radiative Transfer Simulation Tool (DDS)
S. Wolf; L. A. Hillenbrand
2005-06-17T23:59:59.000Z
A WWW interface for the simulation of spectral energy distributions of optically thin dust configurations with an embedded radiative source is presented. The density distribution, radiative source, and dust parameters can be selected either from an internal database or defined by the user. This tool is optimized for studying circumstellar debris disks where large grains are expected to determine the far-infrared through millimeter dust reemission spectral energy distribution. The tool is available at http://aida28.mpia-hd.mpg.de/~swolf/dds
Giant radiation heat transfer through the micron gaps
Nefedov, Igor
2011-01-01T23:59:59.000Z
Near-field heat transfer between two closely spaced radiating media can exceed in orders radiation through the interface of a single black body. This effect is caused by exponentially decaying (evanescent) waves which form the photon tunnel between two transparent boundaries. However, in the mid-infrared range it holds when the gap between two media is as small as few tens of nanometers. We propose a new paradigm of the radiation heat transfer which makes possible the strong photon tunneling for micron thick gaps. For it the air gap between two media should be modified, so that evanescent waves are transformed inside it into propagating ones. This modification is achievable using a metamaterial so that the direct thermal conductance through the metamaterial is practically absent and the photovoltaic conversion of the transferred heat is not altered by the metamaterial.
Application Of A Spherical-Radial Heat Transfer Model To Calculate...
Spherical-Radial Heat Transfer Model To Calculate Geothermal Gradients From Measurements In Deep Boreholes Jump to: navigation, search OpenEI Reference LibraryAdd to library...
Journal of Quantitative Spectroscopy & Radiative Transfer 104 (2007) 384399
Pilon, Laurent
thickness, the single scattering albedo of the materials, and the incident pulse width have been developed inversion schemes accounting for anisotropic scattering. r 2006 Elsevier Ltd. All rights reserved. Keywords is the so-called radiative transfer equation (RTE). It expresses an energy balance in a unit solid angle d
Radiative Transfer Models for Gamma-Ray Bursts
Vurm, Indrek
2015-01-01T23:59:59.000Z
We present global radiative transfer models for heated relativistic jets. The simulations include all relevant radiative processes, starting deep in the opaque zone and following the evolution of radiation to and beyond the photosphere of the jet. The transfer models are compared with three gamma-ray bursts GRB 990123, GRB 090902B, and GRB 130427A, which have well-measured and different spectra. The models provide good fits to the observed spectra in all three cases. The fits give estimates for the jet magnetization parameter $\\varepsilon_{\\rm B}$ and the Lorentz factor $\\Gamma$. In the small sample of three bursts, $\\varepsilon_{\\rm B}$ varies between 0.01 and 0.1, and $\\Gamma$ varies between 340 and 1200.
Veron, Dana E
2009-03-12T23:59:59.000Z
This project had two primary goals: 1) development of stochastic radiative transfer as a parameterization that could be employed in an AGCM environment, and 2) exploration of the stochastic approach as a means for representing shortwave radiative transfer through mixed-phase layer clouds. To achieve these goals, an analysis of the performance of the stochastic approach was performed, a simple stochastic cloud-radiation parameterization for an AGCM was developed and tested, a statistical description of Arctic mixed phase clouds was developed and the appropriateness of stochastic approach for representing radiative transfer through mixed-phase clouds was assessed. Significant progress has been made in all of these areas and is detailed below.
Dana E. Veron
2012-04-09T23:59:59.000Z
This project had two primary goals: (1) development of stochastic radiative transfer as a parameterization that could be employed in an AGCM environment, and (2) exploration of the stochastic approach as a means for representing shortwave radiative transfer through mixed-phase layer clouds. To achieve these goals, climatology of cloud properties was developed at the ARM CART sites, an analysis of the performance of the stochastic approach was performed, a simple stochastic cloud-radiation parameterization for an AGCM was developed and tested, a statistical description of Arctic mixed phase clouds was developed and the appropriateness of stochastic approach for representing radiative transfer through mixed-phase clouds was assessed. Significant progress has been made in all of these areas and is detailed in the final report.
A convective-radiative heat transfer model for gas core reactors
Chen, G.; Anghaie, S. [Univ. of Florida, Gainesville, FL (United States)
1995-12-31T23:59:59.000Z
A convective-radiative heat transfer model is developed and used to predict the temperature distribution in gaseous fuel nuclear reactor cores. The axisymmetric, thin layer Navier-Stokes equations with diffusive radiation source term are the basis for this modeling approach. An algebraic turbulence model is used to calculate the eddy viscosity. The Rosseland diffusion approximation is used to model the radiative heat transfer. A hybrid implicit-explicit numerical scheme with Gauss-Seidel iterative process and a highly stretched grid system near wall is employed to solve the governing equations. Several cases with different internal heat generation rates are modeled and analyzed. Results of the temperature distribution, wall heat flux and the associated Nusselt number are presented. The influence of the internal heat generation rate and the wall temperature on the radiative and convective wall heat fluxes are discussed. At gas and wall temperatures close to 3,500 K and 1,600 K, respectively, the radiative and convective heat transfer rates have similar values.
Radiative heat transfer in 2D Dirac materials
Pablo Rodriguez-Lopez; Wang-Kong Tse; Diego A. R. Dalvit
2015-02-02T23:59:59.000Z
We compute the radiative heat transfer between two sheets of 2D Dirac materials, including topological Chern insulators and graphene, within the framework of the local approximation for the optical response of these materials. In this approximation, which neglects spatial dispersion, we derive both numerically and analytically the short-distance asymptotic of the near-field heat transfer in these systems, and show that it scales as the inverse of the distance between the two sheets. Finally, we discuss the limitations to the validity of this scaling law imposed by spatial dispersion in 2D Dirac materials.
Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2
Liou, K. N.
Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2 A. Hall,1 and K November 2006. [1] We developed a three-dimensional radiative transfer model simulating solar fluxes over (2006), Application of three-dimensional solar radiative transfer to mountains, J. Geophys. Res., 111, D
Radiative heat transfer in a hydrous mantle transition zone Sylvia-Monique Thomas a,n
Jacobsen, Steven D.
Radiative heat transfer in a hydrous mantle transition zone Sylvia-Monique Thomas a,n , Craig R contribute significantly to heat transfer in the mantle and demonstrate the importance of radiative heat, radiative heat transfer was considered relatively unimportant in the mantle. Earlier experimental work
Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau
Paris-Sud XI, Université de
Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped silicon the role of surface plasmons for nanoscale radiative heat transfer between doped silicon surfaces. We derive a new accurate and closed-form expression of the radiative near- field heat transfer. We also
Heat transfer through a water spray curtain under the effect of a strong radiative source
Paris-Sud XI, Université de
Heat transfer through a water spray curtain under the effect of a strong radiative source P. Boulet - mail Pascal.Boulet@lemta.uhp-nancy.fr Keywords : heat transfer, radiative transfer, vaporization, convection, water spray Abstract Heat transfer inside a participating medium, made of droplets flowing in gas
Alan P. Boss
2008-12-12T23:59:59.000Z
The disk instability mechanism for giant planet formation is based on the formation of clumps in a marginally-gravitationally unstable protoplanetary disk, which must lose thermal energy through a combination of convection and radiative cooling if they are to survive and contract to become giant protoplanets. While there is good observational support for forming at least some giant planets by disk instability, the mechanism has become theoretically contentious, with different three dimensional radiative hydrodynamics codes often yielding different results. Rigorous code testing is required to make further progress. Here we present two new analytical solutions for radiative transfer in spherical coordinates, suitable for testing the code employed in all of the Boss disk instability calculations. The testing shows that the Boss code radiative transfer routines do an excellent job of relaxing to and maintaining the analytical results for the radial temperature and radiative flux profiles for a spherical cloud with high or moderate optical depths, including the transition from optically thick to optically thin regions. These radial test results are independent of whether the Eddington approximation, diffusion approximation, or flux-limited diffusion approximation routines are employed. The Boss code does an equally excellent job of relaxing to and maintaining the analytical results for the vertical (theta) temperature and radiative flux profiles for a disk with a height proportional to the radial distance. These tests strongly support the disk instability mechanism for forming giant planets.
He, Xing; Lee, Euntaek; Wilcox, Lucas; Munipalli, Ramakanth; Pilon, Laurent
2013-01-01T23:59:59.000Z
of radiative transfer in combustion systems”, Int. J. Numer.c, “Radiation heat transfer in combustion systems”, Progressin Energy and Combustion Science, vol. 13, no. 2, pp. 97–
Radiative transfer with scattering from closely-spaced spheres
Drolen, B.L.
1986-01-01T23:59:59.000Z
Many heat-transfer applications including fluidized and packed beds, microsphere insulations, and reactor fuel pellets require the analysis of radiative transfer in packed-sphere systems. The radiative properties of surface deposits such as paint and soot layers, and of aerosols such as soot, may be determined by treating them as a collection of spheres. These properties are important for predicting heat transfer in furnaces and flames and for assessing atmospheric attenuation in nuclear-winter scenarios. For many applications when the particle size is larger than the wavelength, or when the volume fraction is small, scattering from individual spheres in the medium is independent of the influence of neighboring particles. Therefore the extinction characteristics of these systems are based on the properties of the discrete particles. This approach is shown to be in good agreement with published experimental data for a packed bed of spheres. When dependent scattering is important, effects caused by the proximity of the neighboring particles must be included. This model examines interference between the scattered waves from each of the particles in the medium. The particle centers correlate via a distribution function which represents the distribution of neighboring particles about a central particle.
Radiative charge transfer in cold and ultracold Sulfur atoms colliding with Protons
Shen, G; Wang, J G; McCann, J F; McLaughlin, B M
2015-01-01T23:59:59.000Z
Radiative decay processes at cold and ultra cold temperatures for Sulfur atoms colliding with protons are investigated. The MOLPRO quantum chemistry suite of codes was used to obtain accurate potential energies and transition dipole moments, as a function of internuclear distance, between low-lying states of the SH$^{+}$ molecular cation. A multi-reference configuration-interaction (MRCI) approximation together with the Davidson correction is used to determine the potential energy curves and transition dipole moments, between the states of interest, where the molecular orbitals (MO's) are obtained from state-averaged multi configuration-self-consistent field (MCSCF) calculations. The collision problem is solved approximately using an optical potential method to obtain radiative loss, and a fully two-channel quantum approach for radiative charge transfer. Cross sections and rate coefficients are determined for the first time for temperatures ranging from 10 $\\mu$ K up to 10,000 K. Results are obtained for all ...
Depletion calculations for the McClellan Nuclear Radiation Center.
Klann, Raymond T.; Newell, Daniel L.
1997-01-01T23:59:59.000Z
FOR THE MCCLELLAN RADIATION CENTER NUCLEAR BY Raymond T.for the McClellan Nuclear Radiation Center Raymond T. KkmnL. Newell McClellan Nuclear Radiation Center SM-ALC/TIR 5335
Impact of surface inhomogeneity on solar radiative transfer under overcast conditions
Li, Zhanqing
Impact of surface inhomogeneity on solar radiative transfer under overcast conditions Zhanqing Li1. Introduction [2] Solar radiative heating is the primary driving force of atmospheric and oceanic movements underlines the impact of surface inhomogeneity on the closure of SW radiative transfer. It also leads
Radiation damage calculation in PHITS Y. Iwamoto1, K. Niita2, T. Sawai1,
McDonald, Kirk
Radiation damage calculation in PHITS 1 Y. Iwamoto1, K. Niita2, T. Sawai1, R.M. Ronningen3, T Feb. 15 Feb. 2012 #12;2 Introduction Radiation damage model in PHITS Radiation damage calculation As the power of proton and heavy-ion accelerators is increasing, the prediction of the structural damage
Howard Barker; Jason Cole
2012-05-17T23:59:59.000Z
Utilization of cloud-resolving models and multi-dimensional radiative transfer models to investigate the importance of 3D radiation effects on the numerical simulation of cloud fields and their properties.
Hogan, Robin
Incorporating the Effects of 3D Radiative Transfer in the Presence of Clouds into Two. The 3D effect on shortwave cloud radiative forcing varies between around 225% and around 1100. Therefore, cumulus clouds are of particular im- portance when considering 3D radiative effects: although
End-to-end calculation of the radiation characteristics of VVER-1000 spent fuel assemblies
Linge, I. I.; Mitenkova, E. F., E-mail: mit@ibrae.ac.ru; Novikov, N. V. [Russian Academy of Sciences, Nuclear Safety Institute (Russian Federation)
2012-12-15T23:59:59.000Z
The results of end-to-end calculation of the radiation characteristics of VVER-1000 spent nuclear fuel are presented. Details of formation of neutron and gamma-radiation sources are analyzed. Distributed sources of different types of radiation are considered. A comparative analysis of calculated radiation characteristics is performed with the use of nuclear data from different ENDF/B and EAF files and ANSI/ANS and ICRP standards.
A GENERAL CIRCULATION MODEL FOR GASEOUS EXOPLANETS WITH DOUBLE-GRAY RADIATIVE TRANSFER
Rauscher, Emily [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721-0092 (United States); Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
2012-05-10T23:59:59.000Z
We present a new version of our code for modeling the atmospheric circulation on gaseous exoplanets, now employing a 'double-gray' radiative transfer scheme, which self-consistently solves for fluxes and heating throughout the atmosphere, including the emerging (observable) infrared flux. We separate the radiation into infrared and optical components, each with its own absorption coefficient, and solve standard two-stream radiative transfer equations. We use a constant optical absorption coefficient, while the infrared coefficient can scale as a power law with pressure; however, for simplicity, the results shown in this paper use a constant infrared coefficient. Here we describe our new code in detail and demonstrate its utility by presenting a generic hot Jupiter model. We discuss issues related to modeling the deepest pressures of the atmosphere and describe our use of the diffusion approximation for radiative fluxes at high optical depths. In addition, we present new models using a simple form for magnetic drag on the atmosphere. We calculate emitted thermal phase curves and find that our drag-free model has the brightest region of the atmosphere offset by {approx}12 Degree-Sign from the substellar point and a minimum flux that is 17% of the maximum, while the model with the strongest magnetic drag has an offset of only {approx}2 Degree-Sign and a ratio of 13%. Finally, we calculate rates of numerical loss of kinetic energy at {approx}15% for every model except for our strong-drag model, where there is no measurable loss; we speculate that this is due to the much decreased wind speeds in that model.
Near field radiative heat transfer between two nonlocal dielectrics
Singer, F; Joulain, Karl
2015-01-01T23:59:59.000Z
We explore in the present work the near-field radiative heat transfer between two semi-infinite parallel nonlocal dielectric planes by means of fluctuational electrodynamics. We use atheory for the nonlocal dielectric permittivityfunction proposed byHalevi and Fuchs. This theory has the advantage to includedifferent models performed in the literature. According to this theory, the nonlocal dielectric function is described by a Lorenz-Drude like single oscillator model, in which the spatial dispersion effects are represented by an additional term depending on the square of the total wavevector k. The theory takes into account the scattering of the electromagneticexcitation at the surface of the dielectric material, which leads to the need of additional boundary conditions in order to solve Maxwell's equations and treat the electromagnetic transmission problem. The additional boundary conditions appear as additional surface scattering parameters in the expressions of the surface impedances. It is shown that the...
Three-dimensional Radiative Transfer Modeling of the Polarization of the Sun's Continuous Spectrum
J. Trujillo Bueno; N. Shchukina
2008-12-18T23:59:59.000Z
Here we formulate and solve the 3D radiative transfer problem of the polarization of the solar continuous radiation. Our approach takes into account not only the anisotropy of the continuum radiation, but also the symmetry-breaking effects caused by the horizontal atmospheric inhomogeneities produced by the solar surface convection. Interestingly, our radiative transfer modeling in a well-known 3D hydrodynamical model of the solar photosphere shows remarkable agreement with the empirical data, significantly better than that obtained via the use of 1D atmospheric models. Although this result confirms that the above-mentioned 3D model was indeed a suitable choice for our Hanle-effect estimation of the substantial amount of "hidden" magnetic energy that is stored in the quiet solar photosphere, we have found however some small discrepancies whose origin may be due to uncertainties in the empirical data and/or in the thermal and density structure of the 3D model. For this reason, we have paid some attention also to other (more familiar) observables, like the center-limb variation of the continuum intensity, which we have calculated taking into account the scattering contribution to the continuum source function. The overall agreement with the observed center-limb variation turns out to be impressive, but we find a hint that the model's temperature gradients in the continuum forming layers could be slightly too steep, perhaps because all current simulations of solar surface convection and magnetoconvection compute the radiative flux divergence ignoring the fact that the effective polarizability is not completely negligible, especially in the downward-moving intergranular lane plasma.
Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method
Yuen, Walter W.
Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method Walter to analyze radiative heat transfer in high porosity insulation materials which have a large scattering for LI900, a material used in the insulation tile for the space shuttle. Comparisons are presented
Fannjiang, Albert
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering, Straining, and Mode and Applied Mathematics Vol. 61, No. 5, pp. 1545-1577 RADIATIVE TRANSFER OF SOUND WAVES IN A RANDOM FLOW the sound wave propagation in a random flow, whose mean flow is large compared with its fluctuation
Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model
Liou, K. N.
Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model of California, Los Angeles, Los Angeles, California B. H. KAHN Jet Propulsion Laboratory, California Institute radiative transfer model has been developed for application to cloudy satellite data assimilation
RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS
Guo, Zhixiong "James"
RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS Kyunghan Kim to incorporate transient radiation heat transfer in tissue welding and soldering with use of ultrafast lasers are performed between laser welding and laser soldering. The use of solder is found to substantially enhance
Goudon, Thierry
A Coupled Model for Radiative Transfer: Doppler Effects, Equilibrium and Non-Equilibrium Diffusion. The interaction terms take into account both scattering and absorption/emission phenomena, as well as Doppler-diffusion equations. Key words. Hydrodynamic limits. Diffusion approximation. Radiative transfer. Doppler correction
Robert, Pincus
A fast, flexible, approximate technique for computing radiative transfer in inhomogeneous cloud.-J. Morcrette, A fast, flexible, approximate technique for computing radiative transfer in inhomogeneous cloud, which computes fluxes at each level. [3] The description of clouds in current LSMs is quite simple: Most
A FAST FORWARD SOLVER OF RADIATIVE TRANSFER HAO GAO AND HONGKAI ZHAO
Soatto, Stefano
finite difference schemes (FD), the finite element method (FEM) [17, 20], the finite volume method (FVM transport equation [4, 13] in the field of neutron transport [4], atmospheric radiative transfer [1], heat. Key words and phrases. radiative transfer equation (RTE), optical imaging, discrete ordinate method
Glass foams: formation, transport properties, and heat, mass, and radiation transfer
Pilon, Laurent
Glass foams: formation, transport properties, and heat, mass, and radiation transfer Andrei G depend, to a large extent, on foams formed on the surface of the molten glass and of the batch due models for thermophysical and transport properties and heat, mass, and radiation transfer in glass foams
SKIRT: the design of a suite of input models for Monte Carlo radiative transfer simulations
Baes, Maarten
2015-01-01T23:59:59.000Z
The Monte Carlo method is the most popular technique to perform radiative transfer simulations in a general 3D geometry. The algorithms behind and acceleration techniques for Monte Carlo radiative transfer are discussed extensively in the literature, and many different Monte Carlo codes are publicly available. On the contrary, the design of a suite of components that can be used for the distribution of sources and sinks in radiative transfer codes has received very little attention. The availability of such models, with different degrees of complexity, has many benefits. For example, they can serve as toy models to test new physical ingredients, or as parameterised models for inverse radiative transfer fitting. For 3D Monte Carlo codes, this requires algorithms to efficiently generate random positions from 3D density distributions. We describe the design of a flexible suite of components for the Monte Carlo radiative transfer code SKIRT. The design is based on a combination of basic building blocks (which can...
T. A. Carroll; M. Kopf; K. G. Strassmeier
2008-07-24T23:59:59.000Z
The major challenges for a fully polarized radiative transfer driven approach to Zeeman-Doppler imaging are still the enormous computational requirements. In every cycle of the iterative interplay between the forward process (spectral synthesis) and the inverse process (derivative based optimization) the Stokes profile synthesis requires several thousand evaluations of the polarized radiative transfer equation for a given stellar surface model. To cope with these computational demands and to allow for the incorporation of a full Stokes profile synthesis into Doppler- and Zeeman-Doppler imaging applications as well as into large scale solar Stokes profile inversions, we present a novel fast and accurate synthesis method for calculating local Stokes profiles. Our approach is based on artificial neural network models, which we use to approximate the complex non-linear mapping between the most important atmospheric parameters and the corresponding Stokes profiles. A number of specialized artificial neural networks, are used to model the functional relation between the model atmosphere, magnetic field strength, field inclination, and field azimuth, on one hand and the individual components (I,Q,U,V) of the Stokes profiles, on the other hand. We performed an extensive statistical evaluation and show that our new approach yields accurate local as well as disk-integrated Stokes profiles over a wide range of atmospheric conditions. The mean rms errors for the Stokes I and V profiles are well below 0.2% compared to the exact numerical solution. Errors for Stokes Q and U are in the range of 1%. Our approach does not only offer an accurate approximation to the LTE polarized radiative transfer it, moreover, accelerates the synthesis by a factor of more than 1000.
Parameterization and Analysis of 3-D Solar Radiative Transfer in Clouds: Final Report
Jerry Y. Harrington
2012-09-21T23:59:59.000Z
This document reports on the research that we have done over the course of our two-year project. The report also covers the research done on this project during a 1 year no-cost extension of the grant. Our work has had two main, inter-related thrusts: The first thrust was to characterize the response of stratocumulus cloud structure and dynamics to systematic changes in cloud infrared radiative cooling and solar heating using one-dimensional radiative transfer models. The second was to couple a three-dimensional (3-D) solar radiative transfer model to the Large Eddy Simulation (LES) model that we use to simulate stratocumulus. The purpose of the studies with 3-D radiative transfer was to examine the possible influences of 3-D photon transport on the structure, evolution, and radiative properties of stratocumulus. While 3-D radiative transport has been examined in static cloud environments, few studies have attempted to examine whether the 3-D nature of radiative absorption and emission influence the structure and evolution of stratocumulus. We undertook this dual approach because only a small number of LES simulations with the 3-D radiative transfer model are possible due to the high computational costs. Consequently, LES simulations with a 1-D radiative transfer solver were used in order to examine the portions of stratocumulus parameter space that may be most sensitive to perturbations in the radiative fields. The goal was then to explore these sensitive regions with LES using full 3-D radiative transfer. Our overall goal was to discover whether 3-D radiative processes alter cloud structure and evolution, and whether this may have any indirect implications for cloud radiative properties. In addition, we collaborated with Dr. Tamas Varni, providing model output fields for his attempt at parameterizing 3-D radiative effects for cloud models.
Robert, Pincus
The Accuracy of Determining Three-Dimensional Radiative Transfer Effects in Cumulus Clouds Using. Three-dimensional radiative transfer effects and why one might estimate them in two-dimensional clouds expensive independent column approximation is called the 3D radiative transfer effect. Assessing
Radiative charge transfer in cold and ultracold Sulfur atoms colliding with Protons
G Shen; P C Stancil; J G Wang; J F McCann; B M McLaughlin
2015-02-25T23:59:59.000Z
Radiative decay processes at cold and ultra cold temperatures for Sulfur atoms colliding with protons are investigated. The MOLPRO quantum chemistry suite of codes was used to obtain accurate potential energies and transition dipole moments, as a function of internuclear distance, between low-lying states of the SH$^{+}$ molecular cation. A multi-reference configuration-interaction (MRCI) approximation together with the Davidson correction is used to determine the potential energy curves and transition dipole moments, between the states of interest, where the molecular orbitals (MO's) are obtained from state-averaged multi configuration-self-consistent field (MCSCF) calculations. The collision problem is solved approximately using an optical potential method to obtain radiative loss, and a fully two-channel quantum approach for radiative charge transfer. Cross sections and rate coefficients are determined for the first time for temperatures ranging from 10 $\\mu$ K up to 10,000 K. Results are obtained for all isotopes of Sulfur, colliding with H$^{+}$ and D$^{+}$ ions and comparison is made to a number of other collision systems.
RADIATIVE TRANSFER SIMULATIONS OF NEUTRON STAR MERGER EJECTA
Tanaka, Masaomi [National Astronomical Observatory of Japan, Mitaka, Tokyo (Japan); Hotokezaka, Kenta, E-mail: masaomi.tanaka@nao.ac.jp, E-mail: hotoke@tap.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto (Japan)
2013-10-01T23:59:59.000Z
Mergers of binary neutron stars (NSs) are among the most promising gravitational wave (GW) sources. Next generation GW detectors are expected to detect signals from NS mergers within about 200 Mpc. The detection of electromagnetic wave (EM) counterparts is crucial to understanding the nature of GW sources. Among the possible EM emission from the NS merger, emission powered by radioactive r-process nuclei is one of the best targets for follow-up observations. However, predictions so far have not taken into account detailed r-process element abundances in the ejecta. We perform for the first time radiative transfer simulations of the NS merger ejecta including all the r-process elements from Ga to U. We show that the opacity of the NS merger ejecta is about ? = 10 cm{sup 2} g{sup –1}, which is higher than that of Fe-rich Type Ia supernova ejecta by a factor of ?100. As a result, the emission is fainter and lasts longer than previously expected. The spectra are almost featureless due to the high expansion velocity and bound-bound transitions of many different r-process elements. We demonstrate that the emission is brighter for a higher mass ratio of the two NSs and a softer equation of state adopted in the merger simulations. Because of the red color of the emission, follow-up observations in red optical and near-infrared (NIR) wavelengths will be the most efficient. At 200 Mpc, the expected brightness of the emission is i = 22-25 AB mag, z = 21-23 AB mag, and 21-24 AB mag in the NIR JHK bands. Thus, observations with wide-field 4 m- and 8 m-class optical telescopes and wide-field NIR space telescopes are necessary. We also argue that the emission powered by radioactive energy can be detected in the afterglow of nearby short gamma-ray bursts.
Graphene-assisted near-field radiative heat transfer between corrugated polar materials
Liu, X. L.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)
2014-06-23T23:59:59.000Z
Graphene has attracted great attention in nanoelectronics, optics, and energy harvesting. Here, the near-field radiative heat transfer between graphene-covered corrugated silica is investigated based on the exact scattering theory. It is found that graphene can improve the radiative heat flux between silica gratings by more than one order of magnitude and alleviate the performance sensitivity to lateral shift. The underlying mechanism is mainly attributed to the improved photon tunneling of modes away from phonon resonances. Besides, coating with graphene leads to nonlocal radiative transfer that breaks Derjaguin's proximity approximation and enables corrugated silica to outperform bulk silica in near-field radiation.
Near-field thermal radiation transfer controlled by plasmons in graphene
Ilic, Ognjen
It is shown that thermally excited plasmon-polariton modes can strongly mediate, enhance, and tune the near-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange ...
Efficient weakly-radiative wireless energy transfer: An EIT-like approach
Hamam, Rafif E.
Inspired by a quantum interference phenomenon known in the atomic physics community as electromagnetically induced transparency (EIT), we propose an efficient weakly radiative wireless energy transfer scheme between two ...
Global oceanic rainfall estimation from AMSR-E data based on a radiative transfer model
Jin, Kyoung-Wook
2006-04-12T23:59:59.000Z
An improved physically-based rainfall algorithm was developed using AMSR-E data based on a radiative transfer model. In addition, error models were designed and embedded in the algorithm to assess retrieval errors ...
Radiation heat transfer in multitube, alkaline-metal thermal-to-electric converter
Tournier, J.M.P.; El-Genk, M.S. [Univ. of New Mexico, Albuquerque, NM (United States)
1999-02-01T23:59:59.000Z
Vapor anode, multitube Alkali-Metal Thermal-to-Electric Converters (AMTECs) are being considered for a number of space missions, such as the NASA Pluto/Express (PX) and Europa missions, scheduled for the years 2004 and 2005, respectively. These static converters can achieve a high fraction of Carnot efficiency at relatively low operating temperatures. An optimized cell can potentially provide a conversion efficiency between 20 and 30 percent, when operated at a hot-side temperature of 1000--1200 K and a cold-side temperature of 550--650 K. A comprehensive modeling and testing program of vapor anode, multitube AMTEC cells has been underway for more than three years at the Air Force Research Laboratory`s Power and Thermal Group (AFRL/VSDVP), jointly with the University of New Mexico`s Institute for Space and Nuclear Power Studies. The objective of this program is to demonstrate the readiness of AMTECs for flight on future US Air Force space missions. A fast, integrated AMTEC Performance and Evaluation Analysis Model (APEAM) has been developed to support ongoing vacuum tests at AFRL and perform analyses and investigate potential design changes to improve the PX-cell performance. This model consists of three major components (Tournier and El-Genk 1998a, b): (a) a sodium vapor pressure loss model, which describes continuum, transition and free-molecule flow regimes in the low-pressure cavity of the cell; (b) an electrochemical and electrical circuit model; and (c) a radiation/conduction heat transfer model, for calculating parasitic heat losses. This Technical Note describes the methodology used to calculate the radiation view factors within the enclosure of the PX-cells, and the numerical procedure developed in this work to determine the radiation heat transport and temperatures within the cell cavity.
atmospheric radiative transfer: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
transfer through the Intergalactic Medium Astrophysics (arXiv) Summary: We use a probabilistic method to compute the propagation of an ionization front corresponding to the...
A Module for Radiation Hydrodynamic Calculations With ZEUS-2D Using Flux-Limited Diffusion
N. J. Turner; J. M. Stone
2001-02-08T23:59:59.000Z
A module for the ZEUS-2D code is described which may be used to solve the equations of radiation hydrodynamics to order unity in v/c, in the flux-limited diffusion (FLD) approximation. In this approximation, the tensor Eddington factor f which closes the radiation moment equations is chosen to be an empirical function of radiation energy density. This is easier to implement and faster than full-transport techniques, in which f is computed by solving the transfer equation. However, FLD is less accurate when the flux has a component perpendicular to the gradient in radiation energy density, and in optically thin regions when the radiation field depends strongly on angle. The material component of the fluid is here assumed to be in local thermodynamic equilibrium. The energy equations are operator-split, with transport terms, radiation diffusion term, and other source terms evolved separately. Transport terms are applied using the same consistent transport algorithm as in ZEUS-2D. The radiation diffusion term is updated using an alternating-direction implicit method with convergence checking. Remaining source terms are advanced together implicitly using numerical root-finding. However when absorption opacity is zero, accuracy is improved by treating compression and expansion source terms using time-centered differencing. Results are discussed for test problems including radiation-damped linear waves, radiation fronts propagating in optically-thin media, subcritical and supercritical radiating shocks, and an optically-thick shock in which radiation dominates downstream pressure.
Paris-Sud XI, Université de
-cooled reactor. It is typically made of many prismatic blocks of graphite in which are inserted the nuclear fuel in the homogenization of heat transfer in periodic porous media where the fluid part is made of long thin parallel in the solid part of the domain and by conduction, convection and radiative transfer in the fluid part (the
New model of calculating the energy transfer efficiency for the spherical theta-pinch device
Xu, G; Loisch, G; Xiao, G; Jacoby, J; Weyrich, K; Li, Y; Zhao, Y
2015-01-01T23:59:59.000Z
Ion-beam-plasma-interaction plays an important role in the field of Warm Dense Matter (WDM) and Inertial Confinement Fusion (ICF). A spherical theta pinch is proposed to act as a plasma target in various applications including a plasma stripper cell. One key parameter for such applications is the free electron density. A linear dependency of this density to the amount of energy transferred into the plasma from an energy storage was found by C. Teske. Since the amount of stored energy is known, the energy transfer efficiency is a reliable parameter for the design of a spherical theta pinch device. The traditional two models of energy transfer efficiency are based on assumptions which comprise the risk of systematical errors. To obtain precise results, this paper proposes a new model without the necessity of any assumption to calculate the energy transfer efficiency for an inductively coupled plasma device. Further, a comparison of these three different models is given at a fixed operation voltage for the full ...
Stramski, Dariusz
Characterization of the solar light field within the ocean mesopelagic zone based on radiative light field Apparent optical properties Mesopelagic zone Radiative transfer modeling a b s t r a c t The solar light field within the ocean from the sea surface to the bottom of the mesopelagic zone
Gitelson, Anatoly
Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative for Sciences, 260 Panama Street, Stanford, CA 94305, USA d Center for Advanced Land Management Information squares regression We used synthetic reflectance spectra generated by a radiative transfer model, PROSPECT
Gitelson, Anatoly
Optimizing spectral indices and chemometric analysis of leaf chemical properties using radiative for Sciences, 260 Panama Street, Stanford, CA 94305, USA d Center for Advanced Land Management Information regression We used synthetic reflectance spectra generated by a radiative transfer model, PROSPECT-5
A Coupled AtmosphereOcean Radiative Transfer System Using the Analytic Four-Stream Approximation
Liou, K. N.
of the ocean. Shortwave radiation from the sun contributes most of the heat fluxes that penetrate the airA Coupled AtmosphereOcean Radiative Transfer System Using the Analytic Four-Stream Approximation WEI-LIANG LEE AND K. N. LIOU Department of Atmospheric and Oceanic Sciences, University of California
Author's personal copy Radiation transfer in photobiological carbon dioxide fixation and fuel
Pilon, Laurent
and fuel production by microalgae Laurent Pilon a,Ã, Halil Berberoglu b,1 , Razmig Kandilian a a Mechanical a c t Solar radiation is the energy source driving the metabolic activity of microorganisms able to photobiologically fixate carbon dioxide and convert solar energy into biofuels. Thus, careful radiation transfer
Radiative Transfer in the Midwave Infrared Applicable to Full Spectrum Atmospheric
Kerekes, John
of the radiative effects in the MWIR is needed. The MWIR is characterized by a unique combination of reduced solar conditions are stressing (e.g., high moisture, heavy aerosol/particulate loading, partial cloud cover, lowRadiative Transfer in the Midwave Infrared Applicable to Full Spectrum Atmospheric Characterization
Radiative heat transfer in a parallelogram shaped cavity
Dez, V Le
2015-01-01T23:59:59.000Z
An exact analytical description of the internal radiative field inside an emitting-absorbing gray semi-transparent medium enclosed in a two-dimensional parallelogram cavity is proposed. The expressions of the incident radiation and the radiative flux field are angularly and spatially discretized with a double Gauss quadrature, and the temperature field is obtained by using an iterative process. Some numerical solutions are tabulated and graphically presented as the benchmark solutions. Temperature and two components of the radiative flux are finally sketched on the whole domain. It is shown that the proposed method gives perfectly smooth results.
Correlation, entropy, and information transfer in black hole radiation
Baocheng Zhang; Qingyu Cai; Mingsheng Zhan; Li You
2014-03-28T23:59:59.000Z
Since the discovery of Hawking radiation, its consistency with quantum theory has been widely questioned. In the widely described picture, irrespective of what initial state a black hole starts with before collapsing, it eventually evolves into a thermal state of Hawking radiations after the black hole is exhausted. This scenario violates the principle of unitarity as required for quantum mechanics and leads to the acclaimed "information loss paradox". This paradox has become an obstacle or a reversed touchstone for any possible theory to unify the gravity and quantum mechanics. Based on the results from Hawking radiation as tunneling, we recently show that Hawking radiations can carry off all information about the collapsed matter in a black hole. After discovering the existence of information-carrying correlation, we show in great detail that entropy is conserved for Hawking radiation based on standard probability theory and statistics. We claim that information previously considered lost remains hidden inside Hawking radiation. More specifically, it is encoded into correlations between Hawking radiations. Our study thus establishes harmony between Harking radiation and the unitarity of quantum mechanics, which establishes the basis for a significant milestone towards resolving the long-standing information loss paradox. The paper provides a brief review of the exciting development on Hawking raidation. In addition to summarize our own work on this subject, we compare and address other related studies.
Influence of Infrared Radiation on Attic Heat Transfer
Katipamula, S.; Turner, W. D.; Murphy, W. E.; O'Neal, D. L.
1985-01-01T23:59:59.000Z
An experimental study concerned with different modes of heal transfer in fibrous and cellulose insulating material is presented. A series of experiments were conducted using an attic simulator to determine the effects of ventilation on attic heat...
Effective-medium model of wire metamaterials in the problems of radiative heat transfer
Mirmoosa, M. S., E-mail: mohammad.mirmoosa@aalto.fi; Nefedov, I. S., E-mail: igor.nefedov@aalto.fi; Simovski, C. R., E-mail: konstantin.simovski@aalto.fi [Department of Radio Science and Engineering, School of Electrical Engineering, Aalto University, P. O. Box 13000, 00076 Aalto (Finland); Rüting, F., E-mail: felix.ruting@uam.es [Departamento de Física Teorica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autonoma de Madrid, E-28049 (Spain)
2014-06-21T23:59:59.000Z
In the present work, we check the applicability of the effective medium model (EMM) to the problems of radiative heat transfer (RHT) through so-called wire metamaterials (WMMs)—composites comprising parallel arrays of metal nanowires. It is explained why this problem is so important for the development of prospective thermophotovoltaic (TPV) systems. Previous studies of the applicability of EMM for WMMs were targeted by the imaging applications of WMMs. The analogous study referring to the transfer of radiative heat is a separate problem that deserves extended investigations. We show that WMMs with practically realizable design parameters transmit the radiative heat as effectively homogeneous media. Existing EMM is an adequate tool for qualitative prediction of the magnitude of transferred radiative heat and of its effective frequency band.
Stephens, Graeme L.
in downwelling radiative fluxes at the surface induced by changes in cloud cover and water vapor distributions. 1An Assessment of the Parameterization of Subgrid-Scale Cloud Effects on Radiative Transfer. Part II form 5 January 2005) ABSTRACT The role of horizontal inhomogeneity in radiative transfer through cloud
Weston, Ken
Prediction of Protein Solubility from Calculation of Transfer Free Energy Harianto Tjong and Huan transfer free energy from the condensed phase to the solution phase was found to predict reasonably well to develop theoretical methods for predicting protein relative and abso- lute solubility. Such methods may
Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 239248
Guo, Zhixiong "James"
method such as decomposition method, and it takes a CPU time that is proportional to the third power of ; Stabilized bi-conjugate gradient method (BiCGSTAB); Thermal radiation 1. Introduction It is important
Paris-Sud XI, UniversitÃ© de
of radiative transfer model for assessing solar radiation: the relative importance of atmospheric constituents, Germany * Corresponding Author, armel.oumbe@ensmp.fr Abstract Solar radiation is modified in its way: solar radiation, atmospheric optics, satellite images, Heliosat method 1. Introduction A wealth
Journal of Quantitative Spectroscopy & Radiative Transfer 99 (2006) 341348
2006-01-01T23:59:59.000Z
structure on non-LTE, non-diffusive radiation transport and X-ray production is discussed. r 2005 Elsevier Ltd. All rights reserved. Keywords: Z-pinch plasma; K-shell X-ray production and spectroscopy; Opacity tungsten wires [2]. Strong j Â B forces implode the wire array, which generates nearly 2 MJ of X-rays in o
PRECONDITIONED BI-CONJUGATE GRADIENT METHOD FOR RADIATIVE TRANSFER IN SPHERICAL MEDIA
Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, Bangalore 560 034 (India); Paletou, F.; Leger, L. [Laboratoire d'Astrophysique de Toulouse-Tarbes, Universite de Toulouse, CNRS, 14 Ave. E. Belin, 31400 Toulouse (France)
2009-10-10T23:59:59.000Z
A robust numerical method called the Preconditioned Bi-Conjugate Gradient (Pre-BiCG) method is proposed for the solution of the radiative transfer equation in spherical geometry. A variant of this method called Stabilized Preconditioned Bi-Conjugate Gradient (Pre-BiCG-STAB) is also presented. These are iterative methods based on the construction of a set of bi-orthogonal vectors. The application of the Pre-BiCG method in some benchmark tests shows that the method is quite versatile, and can handle difficult problems that may arise in astrophysical radiative transfer theory.
Nonlocal study of the near field radiative heat transfer between two n-doped semiconductors
Singer, F; Joulain, Karl
2015-01-01T23:59:59.000Z
We study in this work the near-field radiative heat transfer between two semi-infinite parallel planes of highly n-doped semiconductors. Using a nonlocal model of the dielectric permittivity, usually used for the case of metallic planes, we show that the radiative heat transfer coefficientsaturates as the separation distance is reduced for high doping concentration. These results replace the 1/d${}^2$ infinite divergence obtained in the local model case. Different features of the obtained results are shown to relate physically to the parameters of the materials, mainly the doping concentration and the plasmon frequency.
da Costa, Fatima Rubio; Petrosian, Vahe'; Carlsson, Mats
2015-01-01T23:59:59.000Z
Solar flares involve complex processes that are coupled together and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present such a model to simulate the coupling of high-energy particle kinetics with hydrodynamics of the atmospheric plasma. We combine the Stanford unified Fokker-Planck code that models particle acceleration, transport, and bremsstrahlung radiation with the RADYN hydrodynamic code that models the atmospheric response to collisional heating by non-thermal electrons through detailed radiative transfer calculations. We perform simulations using different injection electron spectra, including an {\\it ad hoc} power law and more realistic spectra predicted by the stochastic acceleration model due to turbulence or plasma waves. Surprisingly, stochastically accelerated electrons, even with energy flux $\\ll 10^{10}$ erg s$^{-1}$ cm$^{-2}$, cause "explosive" chromospheric evaporation and drive stronger up- an...
Heat-transfer calculations for a potted (solid matrix embedded) subassembly
Betten, P.R.
1984-01-01T23:59:59.000Z
Standard Liquid Metal Fast Breeder Reactor (LMFBR) subassemblies used in the Experimental Breeder Reactor II (EBR-II) have been investigated for fuel-bundle distortion using a destructive examination method known as potting. The potting technique embeds and permanently fixes the fuel elements in a solid matrix that can be sectioned and polished to reveal details in the internal structure of the elements or subassembly. Thus, an advantage of the potting technique is that it permits investigation of the internal structure of the subassembly in situ, as this structure would be lost or significantly altered during subassembly disassembly. However, since the elements in the subassembly are radioactive, the potting material must efficiently conduct radioactive decay heat to the environment so that the melting or softening temperatures of the potting material are not exceeded. The purpose of this paper is to present the heat transfer calculations for a potted subassembly and to recommend a simplified method for solving similar problems.
Zhao, J.M., E-mail: jmzhao@hit.edu.cn [School of Energy Science and Engineering, Harbin Institute of Technology, 92 West Dazhi Street, Harbin 150001, People's Republic of China (China); Tan, J.Y., E-mail: tanjy@hit.edu.cn [School of Auto Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai 264209, People's Republic of China (China); Liu, L.H., E-mail: lhliu@hit.edu.cn [School of Energy Science and Engineering, Harbin Institute of Technology, 92 West Dazhi Street, Harbin 150001, People's Republic of China (China); School of Auto Engineering, Harbin Institute of Technology at Weihai, 2 West Wenhua Road, Weihai 264209, People's Republic of China (China)
2013-01-01T23:59:59.000Z
A new second order form of radiative transfer equation (named MSORTE) is proposed, which overcomes the singularity problem of a previously proposed second order radiative transfer equation [J.E. Morel, B.T. Adams, T. Noh, J.M. McGhee, T.M. Evans, T.J. Urbatsch, Spatial discretizations for self-adjoint forms of the radiative transfer equations, J. Comput. Phys. 214 (1) (2006) 12-40 (where it was termed SAAI), J.M. Zhao, L.H. Liu, Second order radiative transfer equation and its properties of numerical solution using finite element method, Numer. Heat Transfer B 51 (2007) 391-409] in dealing with inhomogeneous media where some locations have very small/zero extinction coefficient. The MSORTE contains a naturally introduced diffusion (or second order) term which provides better numerical property than the classic first order radiative transfer equation (RTE). The stability and convergence characteristics of the MSORTE discretized by central difference scheme is analyzed theoretically, and the better numerical stability of the second order form radiative transfer equations than the RTE when discretized by the central difference type method is proved. A collocation meshless method is developed based on the MSORTE to solve radiative transfer in inhomogeneous media. Several critical test cases are taken to verify the performance of the presented method. The collocation meshless method based on the MSORTE is demonstrated to be capable of stably and accurately solve radiative transfer in strongly inhomogeneous media, media with void region and even with discontinuous extinction coefficient.
Lyalpha RADIATIVE TRANSFER WITH DUST: ESCAPE FRACTIONS FROM SIMULATED HIGH-REDSHIFT GALAXIES
Laursen, Peter; Sommer-Larsen, Jesper; Andersen, Anja C., E-mail: pela@dark-cosmology.d, E-mail: jslarsen@astro.ku.d [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100, Copenhagen Oe (Denmark)
2009-10-20T23:59:59.000Z
The Lyalpha emission line is an essential diagnostic tool for probing galaxy formation and evolution. Not only is it commonly the strongest observable line from high-redshift galaxies, but from its shape detailed information about its host galaxy can be revealed. However, due to the scattering nature of Lyalpha photons increasing their path length in a nontrivial way, if dust is present in the galaxy, the line may be severely suppressed and its shape altered. In order to interpret observations correctly, it is thus of crucial significance to know how much of the emitted light actually escapes the galaxy. In the present work, using a combination of high-resolution cosmological hydrosimulations and an adaptively refinable Monte Carlo Lyalpha radiative transfer code including an environment dependent model of dust, the escape fractions f {sub esc} of Lyalpha radiation from high-redshift (z = 3.6) galaxies are calculated. In addition to the average escape fraction, the variation of f {sub esc} in different directions and from different parts of the galaxies is investigated, as well as the effect on the emergent spectrum. Escape fractions from a sample of simulated galaxies of representative physical properties are found to decrease for increasing galaxy virial mass M {sub vir}, from f {sub esc} approaching unity for M {sub vir} approx 10{sup 9} M {sub sun} to f {sub esc} less than 10% for M {sub vir} approx 10{sup 12} M {sub sun}. In spite of dust being almost gray, it is found that the emergent spectrum is affected nonuniformly, with the escape fraction of photons close to the line center being much higher than of those in the wings, thus effectively narrowing the Lyalpha line.
Radiation Skyshine Calculation with MARS15 for the mu2e Experiment at Fermilab
Leveling, A F
2015-01-01T23:59:59.000Z
The Fermilab Antiproton source is to be repurposed to provide an 8 kW proton beam to the Mu2e experiment by 1/3 integer, slow resonant extraction. Shielding provided by the existing facility must be supplemented with in-tunnel shielding to limit the radiation effective dose rate above the shield in the AP30 service building. In addition to the nominal radiation shield calculations, radiation skyshine calculations were required to ensure compliance with Fermilab Radiological Control Manual. A complete model of the slow resonant extraction system including magnets, electrostatic septa, magnetic fields, tunnel enclosure with shield, and a nearby exit stairway are included in the model. The skyshine model extends above the beam enclosure surface to 10 km vertically and 5 km radially.
ARM - Publications: Science Team Meeting Documents: ARM Radiative Transfer
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa-Anomalous Radiative AbsorptionARM In TheACloudStatus,Newatmospheric profilesModeling
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering and ModeCoupling
Ryzhik, Lenya
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering and ModeÂCoupling Albert the sound wave propagation in a random flow, whose mean flow is large compared with its fluctuation and the turbulent scattering and modeÂcoupling of sound waves. We show that, because of the flowÂstraining term
BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1
Naylor, David A.
radiance incident on the spectrometer/radiometer. Computer simulations, known as radiative transfer models source of opacity at submillimetre wavelengths where many objects emit most of their energy. Although high altitude observatories (such as the James Clerk Maxwell Telescope (JCMT) in Hawaii and the Atacama
CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL
Heinemann, Detlev
CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL Enio B-970, SP, Brazil. Phone + 55 12 39456741, Fax + 55 12 39456810, fernando@dge.inpe.br. Samuel L. Abreu, Hans, Federal University of Santa Catarina -UFSC, Florianópolis, 88040-900, (SC), Brazil. Richard Perez
Levis, Aviad; Aides, Amit; Davis, Anthony B
2015-01-01T23:59:59.000Z
This paper introduces a method to preform optical tomography, using 3D radiative transfer as the forward model. We use an iterative approach predicated on the Spherical Harmonics Discrete Ordinates Method (SHDOM) to solve the optimization problem in a scalable manner. We illustrate with an application in remote sensing of a cloudy atmosphere.
Shape-independent limits to near-field radiative heat transfer
Miller, Owen D; Rodriguez, Alejandro W
2015-01-01T23:59:59.000Z
We derive shape-independent limits to the spectral radiative heat-transfer rate between two closely spaced bodies, generalizing the concept of a black body to the case of near-field energy transfer. By conservation of energy, we show that each body of susceptibility $\\chi$ can emit and absorb radiation at enhanced rates bounded by $|\\chi|^2 / \\operatorname{Im} \\chi$, optimally mediated by near-field photon transfer proportional to $1/d^2$ across a separation distance $d$. Dipole--dipole and dipole--plate structures approach restricted versions of the limit, but common large-area structures do not exhibit the material enhancement factor and thus fall short of the general limit. By contrast, we find that particle arrays interacting in an idealized Born approximation exhibit both enhancement factors, suggesting the possibility of orders-of-magnitude improvement beyond previous designs and the potential for radiative heat transfer to be comparable to conductive heat transfer through air at room temperature, and s...
Liberman, M A; Kiverin, A D
2015-01-01T23:59:59.000Z
In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. Th...
Calculation of radiation therapy dose using all particle Monte Carlo transport
Chandler, William P. (Tracy, CA); Hartmann-Siantar, Christine L. (San Ramon, CA); Rathkopf, James A. (Livermore, CA)
1999-01-01T23:59:59.000Z
The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media.
Calculation of radiation therapy dose using all particle Monte Carlo transport
Chandler, W.P.; Hartmann-Siantar, C.L.; Rathkopf, J.A.
1999-02-09T23:59:59.000Z
The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media. 57 figs.
Boyer, Edmond
equilibrium; Application to reflooding of a nuclear reactor. Miloud Chahlafia,b,c , Fabien Belleta,b , Florian Transfer 55, 13-14 (2012) 3666-3676" DOI : 10.1016/j.ijheatmasstransfer.2012.02.067 #12;nuclear reactor flux Indexes - At the calculation point -+ Dimensionless 3 hal-00680676,version1-19Mar2012 #12;-(j) jth
Effect of radiative heat transfer on the coagulation dynamics of combustion-generated particles
Mackowski, D.W. (Auburn Univ., AL (United States)); Tassopoulos, M.; Rosner, D.E. (Yale Univ., New Haven, CT (United States))
1994-01-01T23:59:59.000Z
We examine the influences of radiation heat transfer on the size and number density evolution of small coagulating particles. On a microscopic level, radiative emission and/or absorption by the particle will perturb the gas temperature field adjacent to each particle. As a result of thermophoretic particle transport, the nonequilibrium condition can alter the collision rates with neighboring particles. A simplified analysis of the thermophoretic coagulation mechanism suggests that net radiative cooling of the particles can lead to an accelerated growth of [mu]m-sized particles, whereas net radiative heating can act to essentially freeze coagulation rates. On the macroscopic level, the addition or removal of heat in the gas through radiative absorption emission by the particle cloud can also significantly alter, through thermophoretic transport, the local particle number density. Under certain cases these effects can augment the accelerated coagulation rates that occur under radiative cooling conditions. We also examine the particular situation of equilibrium between particle cloud radiative absorption and emission - which results in no net macroscopic effect on the gas. 30 refs., 9 figs.
Greendyke, Robert Brian
1988-01-01T23:59:59.000Z
will examine the radiance model and various step models in order to determine their appropriateness to the flight regime of the AOTV. The final area to be investigated will be the effect of nonequilibrium corrections on the radiative heat transfer models... of T and e T will be valid as long as there is a reasonable amount vNs of nitrogen molecules in the flow. Radiative Heat Transfer Models For this study, four radiative heat transfer models were examined. One of these models is an optically thin radiance...
Svend-Age Biehs
2011-03-15T23:59:59.000Z
We investigate the thermal radiation and thermal near-field energy density of a metal-coated semi-infinite body for different substrates. We show that the surface polariton coupling within the metal coating leads to an enhancement of the TM-mode part of the thermal near-field energy density when a polar substrate is used. In this case the result obtained for a free standing metal film is retrieved. In contrast, in the case of a metal substrate there is no enhancement in the TM-mode part, as can also be explained within the framework of surface plasmon coupling within the coating. Finally, we discuss the influence of the enhanced thermal energy density on the near-field radiative heat transfer between a simple semi-infinite and a coated semi-infinite body for different material combinations.
Non-contact pumping of light emitters via non-radiative energy transfer
Klimov, Victor I. (Los Alamos, NM); Achermann, Marc (Los Alamos, NM)
2010-01-05T23:59:59.000Z
A light emitting device is disclosed including a primary light source having a defined emission photon energy output, and, a light emitting material situated near to said primary light source, said light emitting material having an absorption onset equal to or less in photon energy than the emission photon energy output of the primary light source whereby non-radiative energy transfer from said primary light source to said light emitting material can occur yielding light emission from said light emitting material.
PARALLEL COMPUTATIONS OF RADIATIVE HEAT TRANSFER USING THE DISCRETE ORDINATES METHOD
Utah, University of
of the important radiatively active species (CO2, H2O, soot) and temperature, which are calculated on the spatially increasingly tractable. Issues relating to the use of high-performance computing in participating media heat properties. First we summarize previous applications of spatial decomposition strategies to finite
Time-dependent Radiation Transfer in the Internal Shock Model Scenario for Blazar Jets
Manasvita Joshi; Markus Boettcher
2010-11-13T23:59:59.000Z
We describe the time-dependent radiation transfer in blazar jets, within the internal shock model. We assume that the central engine, which consists of a black hole and an accretion disk, spews out relativistic shells of plasma with different velocity, mass, and energy. We consider a single inelastic collision between a faster (inner) and a slower (outer) moving shell. We study the dynamics of the collision and evaluate the subsequent emission of radiation via the synchrotron and synchrotron self Compton (SSC) processes after the interaction between the two shells has begun. The collision results in the formation of a forward shock (FS) and a reverse shock (RS) that convert the ordered bulk kinetic energy of the shells into magnetic field energy and accelerate the particles, which then radiate. We assume a cylindrical geometry for the emission region of the jet. We treat the self-consistent radiative transfer by taking into account the inhomogeneity in the photon density throughout the region. In this paper, we focus on understanding the effects of varying relevant input parameters on the simulated spectral energy distribution (SED) and spectral variability patterns.
Delgado-Correal, Camilo; Castaño, Gabriel
2012-01-01T23:59:59.000Z
Radiative transfer models explain and predict interaction between solar radiation and the different elements present in the atmosphere, which are responsible for energy attenuation. In Colombia there have been neither measurements nor studies of atmospheric components such as gases and aerosols that can cause turbidity and pollution. Therefore satellite images cannot be corrected radiometrically in a proper way. When a suitable atmospheric correction is carried out, loss of information is avoided, which may be useful for discriminating image land cover. In this work a computational model was used to find radiative atmospheric attenuation (300 1000nm wavelength region) on an equatorial tropical desert (La Tatacoa, Colombia) in order to conduct an adequate atmospheric correction.
Calculation of synchrotron radiation from high intensity electron beam at eRHIC
Jing Y.; Chubar, O.; Litvinenko, V.
2012-05-20T23:59:59.000Z
The Electron-Relativistic Heavy Ion Collider (eRHIC) at Brookhaven National Lab is an upgrade project for the existing RHIC. A 30 GeV energy recovery linac (ERL) will provide a high charge and high quality electron beam to collide with proton and ion beams. This will improve the luminosity by at least 2 orders of magnitude. The synchrotron radiation (SR) from the bending magnets and strong quadrupoles for such an intense beam could be penetrating the vacuum chamber and producing hazards to electronic devices and undesired background for detectors. In this paper, we calculate the SR spectral intensity, power density distributions and heat load on the chamber wall. We suggest the wall thickness required to stop the SR and estimate spectral characteristics of the residual and scattered background radiation outside the chamber.
Joulain, Karl; Drevillon, Jeremie; Ben-Abdallah, Philippe
2015-01-01T23:59:59.000Z
We show in this article that phase change materials (PCM) exhibiting a phase transition between a dielectric state and a metallic state are good candidates to perform modulation as well as amplification of radiative thermal flux. We propose a simple situation in plane parallel geometry where a so-called radiative thermal transistor could be achieved. In this configuration, we put a PCM between two blackbodies at different temperatures. We show that the transistor effect can be achieved easily when this material has its critical temperature between the two blackbody temperatures. We also see, that the more the material is reflective in the metallic state, the more switching effect is realized whereas the more PCM transition is stiff in temperature, the more thermal amplification is high. We finally take the example of VO2 that exhibits an insulator-metallic transition at 68{\\textdegree}C. We show that a demonstrator of a radiative transistor could easily be achieved in view of the heat flux levels predicted. F...
Lee, K.H.; Lee, J.S.; Choi, M. [Seoul National Univ. (Korea, Republic of). Dept. of Mechanical Engineering
1996-02-09T23:59:59.000Z
In the outside vapor deposition (OVD) process, silica particles are deposited by thermophoretic force on the surface of a cylinder. This process is associated with complex physical phenomena such as heat transfer between a torch and a cylinder, chemical reaction for silica particle formation, and particle deposition. Since the OVD process is carried out in a very high temperature environment, radiative heat transfer should be taken into consideration. Here, the radiative-convective heat transfer around a circular cylinder in a cross flow of a radiating gas has been numerically analyzed using the finite volume radiation solution method in a nonorthogonal coordinate system. The cross-flow Reynolds number based on the cylinder diameter is 40, and the fluid Prandtl number is assumed to be 0.7. The radiative heat transfer coupled with convection is reasonably predicted by the finite volume radiation solution method. Distributions of the local Nusselt number are investigated according to the variation of radiation parameters such as conduction-to-radiation parameter, optical thickness, scattering albedo, and cylinder wall emissivity.
Wang, Chenxi
2013-07-25T23:59:59.000Z
observations and fast radiative transfer models (RTMs). In the first part, we develop two computationally efficient RTMs simulating satellite observations under cloudy-sky conditions in the visible/shortwave infrared (VIS/SWIR) and thermal inferred (IR...
Greendyke, Robert Brian
1988-01-01T23:59:59.000Z
A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN GREENDYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1988 Major Subject: Aerospace Engineering A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN...
Biggs, P.J. (Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston (United States))
1991-10-01T23:59:59.000Z
Shielding calculations for door thicknesses for megavoltage radiotherapy facilities with mazes are generally straightforward. To simplify the calculations, the standard formalism adopts several approximations relating to the average beam path, scattering coefficients, and the mean energy of the spectrum of scattered radiation. To test the accuracy of these calculations, the Monte Carlo program, ITS, was applied to this problem by determining the dose and energy spectrum of the radiation at the door for 4- and 10-MV bremsstrahlung beams incident on a phantom at isocenter. This was performed for mazes, one termed 'standard' and the other a shorter maze where the primary beam is incident on the wall adjacent to the door. The peak of the photon-energy spectrum at the door was found to be the same for both types of maze, independent of primary beam energy, and also, in the case of the conventional maze, of the primary beam orientation. The spectrum was harder for the short maze and for 10 MV vs. 4 MV. The thickness of the lead door for a short maze configuration was 1.5 cm for 10 MV and 1.2 cm for 4 MV vs. approximately less than 1 mm for a conventional maze. For the conventional maze, the Monte Carlo calculation predicts the dose at the door to be lower than given by NCRP 49 and NCRP 51 by about a factor of 2 at 4 MV but to be the same at 10 MV. For the short maze, the Monte Carlo predicts the dose to be a factor of 3 lower for 4 MV and about a factor of 1.5 lower for 10 MV. Experimental results support the Monte Carlo findings for the short maze.
Bergstrom, Paul M. (Livermore, CA); Daly, Thomas P. (Livermore, CA); Moses, Edward I. (Livermore, CA); Patterson, Jr., Ralph W. (Livermore, CA); Schach von Wittenau, Alexis E. (Livermore, CA); Garrett, Dewey N. (Livermore, CA); House, Ronald K. (Tracy, CA); Hartmann-Siantar, Christine L. (Livermore, CA); Cox, Lawrence J. (Los Alamos, NM); Fujino, Donald H. (San Leandro, CA)
2000-01-01T23:59:59.000Z
A system and method is disclosed for radiation dose calculation within sub-volumes of a particle transport grid. In a first step of the method voxel volumes enclosing a first portion of the target mass are received. A second step in the method defines dosel volumes which enclose a second portion of the target mass and overlap the first portion. A third step in the method calculates common volumes between the dosel volumes and the voxel volumes. A fourth step in the method identifies locations in the target mass of energy deposits. And, a fifth step in the method calculates radiation doses received by the target mass within the dosel volumes. A common volume calculation module inputs voxel volumes enclosing a first portion of the target mass, inputs voxel mass densities corresponding to a density of the target mass within each of the voxel volumes, defines dosel volumes which enclose a second portion of the target mass and overlap the first portion, and calculates common volumes between the dosel volumes and the voxel volumes. A dosel mass module, multiplies the common volumes by corresponding voxel mass densities to obtain incremental dosel masses, and adds the incremental dosel masses corresponding to the dosel volumes to obtain dosel masses. A radiation transport module identifies locations in the target mass of energy deposits. And, a dose calculation module, coupled to the common volume calculation module and the radiation transport module, for calculating radiation doses received by the target mass within the dosel volumes.
Soljaèiæ, Marin
2012-01-01T23:59:59.000Z
in graphene Ognjen Ilic,1,* Marinko Jablan,2 John D. Joannopoulos,1 Ivan Celanovic,3 Hrvoje Buljan,2 and Marin-field radiation transfer between two closely separated graphene sheets. The dependence of near-field heat exchange interband or intraband processes. We predict maximum transfer at low doping and for plasmons in two graphene
Boyer, Edmond
Eurotherm Seminar N°81 Reactive Heat Transfer in Porous Media, Ecole des Mines d'Albi, France June 4-6, 2007 ET81- 1 HEAT TRANSFER BY SIMULTANEOUS RADIATION-CONDUCTION AND CONVECTION IN A HIGH for the packed bed. The comparison between the radiative heat transfer and the exchanges by conduction and forced
Investigation of Radiation and Chemical Resistance of Flexible HLW Transfer Hose
E. Skidmore; Billings, K.; Hubbard, M.
2010-03-24T23:59:59.000Z
A chemical transfer hose constructed of an EPDM (ethylene-propylene diene monomer) outer covering with a modified cross-linked polyethylene (XLPE) lining was evaluated for use in high level radioactive waste transfer applications. Laboratory analysis involved characterization of the hose liner after irradiation to doses of 50 to 300 Mrad and subsequent exposure to 25% NaOH solution at 93 C for 30 days, simulating 6 months intermittent service. The XLPE liner mechanical and structural properties were characterized at varying dose levels. Burst testing of irradiated hose assemblies was also performed. Literature review and test results suggest that radiation effects below doses of 100 kGy are minimal, with acceptable property changes to 500 kGy. Higher doses may be feasible. At a bounding dose of 2.5 MGy, the burst pressure is reduced to the working pressure (1.38 MPa) at room temperature. Radiation exposure slightly reduces liner tensile strength, with more significant decrease in liner elongation. Subsequent exposure to caustic solutions at elevated temperature slightly increases elongation, suggesting an immersion/hydrolytic effect or possible thermal annealing of radiation damage. This paper summarizes the laboratory results and recommendations for field deployment.
Varivtsev, A. V., E-mail: vav3@niiar.ru; Zhemkov, I. Yu. [JSC “SSC RIAR,” Dimitrovgrad-10 (Russian Federation)
2014-12-15T23:59:59.000Z
The application of the improved method for calculating the radiation heat generation in the elements of an experimental device located at the periphery of the BOR-60 reactor core results in a significant reduction in the discrepancies between the calculated and the experimental data. This allows us to conclude that the improved method has an advantage over the one used earlier.
Alan M. Watson; William J. Henney
2001-08-30T23:59:59.000Z
We describe an efficient Monte Carlo algorithm for a restricted class of scattering problems in radiation transfer. This class includes many astrophysically interesting problems, including the scattering of ultraviolet and visible light by grains. The algorithm correctly accounts for multiply-scattered light. We describe the algorithm, present a number of important optimizations, and explicity show how the algorithm can be used to estimate quantities such as the emergent and mean intensity. We present two test cases, examine the importance of the optimizations, and show that this algorithm can be usefully applied to optically-thin problems, a regime sometimes considered limited to explicit single-scattering plus attenuation approximations.
Analytical Green's function of the radiative transfer radiance for the infinite medium
Liemert, Andre; Kienle, Alwin [Institut fuer Lasertechnologien in der Medizin und Messtechnik, Helmholtzstrasse12, D-89081 Ulm (Germany)
2011-03-15T23:59:59.000Z
An analytical solution of the radiative transfer equation for the radiance caused by an isotropic source which is located in an infinitely extended medium was derived using the P{sub N} method. The results were compared with Monte Carlo simulations and excellent agreement was found. In addition, the radiance of the SP{sub N} approximation for the same geometry was derived. Comparison with Monte Carlo simulations showed that the SP{sub N} radiance, although being more exact than the radiance derived from diffusion theory, has relatively large errors in many relevant cases.
Radiative heat transfer between two dielectric nanogratings in the scattering approach
J. Lussange; R. Guérout; F. S. S. Rosa; J. -J. Greffet; A. Lambrecht; S. Reynaud
2012-06-01T23:59:59.000Z
We present a theoretical study of radiative heat transfer between dielectric nanogratings in the scattering approach. As a comparision with these exact results, we also evaluate the domain of validity of Derjaguin's Proximity Approximation (PA). We consider a system of two corrugated silica plates with various grating geometries, separation distances, and lateral displacement of the plates with respect to one another. Numerical computations show that while the PA is a good approximation for aligned gratings, it cannot be used when the gratings are laterally displaced. We illustrate this by a thermal modulator device for nanosystems based on such a displacement.
Multi--dimensional Cosmological Radiative Transfer with a Variable Eddington Tensor Formalism
Nickolay Y. Gnedin; Tom Abel
2001-06-15T23:59:59.000Z
We present a new approach to numerically model continuum radiative transfer based on the Optically Thin Variable Eddington Tensor (OTVET) approximation. Our method insures the exact conservation of the photon number and flux (in the explicit formulation) and automatically switches from the optically thick to the optically thin regime. It scales as N logN with the number of hydrodynamic resolution elements and is independent of the number of sources of ionizing radiation (i.e. works equally fast for an arbitrary source function). We also describe an implementation of the algorithm in a Soften Lagrangian Hydrodynamic code (SLH) and a multi--frequency approach appropriate for hydrogen and helium continuum opacities. We present extensive tests of our method for single and multiple sources in homogeneous and inhomogeneous density distributions, as well as a realistic simulation of cosmological reionization.
RADIATION HEAT TRANSFER ENVIRONMENT IN FIRE AND FURNACE TESTS OF RADIOACTIVE MATERIALS PAKCAGES
Smith, A
2008-12-31T23:59:59.000Z
The Hypothetical Accident Conditions (HAC) sequential test of radioactive materials packages includes a thermal test to confirm the ability of the package to withstand a transportation fire event. The test specified by the regulations (10 CFR 71) consists of a 30 minute, all engulfing, hydrocarbon fuel fire, with an average flame temperature of at least 800 C. The requirements specify an average emissivity for the fire of at least 0.9, which implies an essentially black radiation environment. Alternate test which provide equivalent total heat input at the 800 C time averaged environmental temperature may also be employed. When alternate tests methods are employed, such as furnace or gaseous fuel fires, the equivalence of the radiation environment may require justification. The effects of furnace and open confinement fire environments are compared with the regulatory fire environment, including the effects of gases resulting from decomposition of package overpack materials. The results indicate that furnace tests can produce the required radiation heat transfer environment, i.e., equivalent to the postulated pool fire. An open enclosure, with transparent (low emissivity) fire does not produce an equivalent radiation environment.
Zav'yalkin, F.M.; Osipov, S.P.
1986-08-01T23:59:59.000Z
This paper describes a method of calculating the scattering function for a linear array of detectors. The authors consider the detector arrangement which in the best way utilizes the radiation flux but which to the greatest extent is affected by the scattering of radiation from one detector to another: optically separated scintillatorsf in the form of parallelepipeds are assumed to be closely packed in a linear array and directed toward the radiation source. In order to obtain estimates of the scattering function with an accuracy of 3-5% for x close to zero at radiation not less than 2 MeV, the leakage of secondary electrons are taken into account.
Taylor, Michael, E-mail: michael.taylor@rmit.edu.au [School of Applied Sciences, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria (Australia); Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Dunn, Leon; Kron, Tomas; Height, Felicity; Franich, Rick [School of Applied Sciences, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria (Australia); Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia)
2012-04-01T23:59:59.000Z
Prediction of dose distributions in close proximity to interfaces is difficult. In the context of radiotherapy of lung tumors, this may affect the minimum dose received by lesions and is particularly important when prescribing dose to covering isodoses. The objective of this work is to quantify underdosage in key regions around a hypothetical target using Monte Carlo dose calculation methods, and to develop a factor for clinical estimation of such underdosage. A systematic set of calculations are undertaken using 2 Monte Carlo radiation transport codes (EGSnrc and GEANT4). Discrepancies in dose are determined for a number of parameters, including beam energy, tumor size, field size, and distance from chest wall. Calculations were performed for 1-mm{sup 3} regions at proximal, distal, and lateral aspects of a spherical tumor, determined for a 6-MV and a 15-MV photon beam. The simulations indicate regions of tumor underdose at the tumor-lung interface. Results are presented as ratios of the dose at key peripheral regions to the dose at the center of the tumor, a point at which the treatment planning system (TPS) predicts the dose more reliably. Comparison with TPS data (pencil-beam convolution) indicates such underdosage would not have been predicted accurately in the clinic. We define a dose reduction factor (DRF) as the average of the dose in the periphery in the 6 cardinal directions divided by the central dose in the target, the mean of which is 0.97 and 0.95 for a 6-MV and 15-MV beam, respectively. The DRF can assist clinicians in the estimation of the magnitude of potential discrepancies between prescribed and delivered dose distributions as a function of tumor size and location. Calculation for a systematic set of 'generic' tumors allows application to many classes of patient case, and is particularly useful for interpreting clinical trial data.
Calculation of unsteady-state heat and mass transfer in steam injection wells
Ruddy, Kenneth Edward
1986-01-01T23:59:59.000Z
) and (5) are defined as the fluid flow equations for the gas and liquid phases, respectively. Mass Balance E uation The thermodynamic system under consideration is a vertical cylindri- cal conduit as depicted in figure 1. A mass balance applied... Equation Method of Solution. RESULTS Comparison with Field Data. Comparison with Results from Steady-State Mass Transfer Model CONCLUSIONS NOMENCLATURE . REFERENCES APPENDIX A: TURBULENCE FACTOR. APPENDIX B: RELATIVE FLUID CONDUCTIVITT. Page vi...
Vladislav V. Serov; A. S. Kheifets
2014-10-30T23:59:59.000Z
We analyze a transfer ionization (TI) reaction in the fast proton-helium collision $\\rm H^+ + He \\to H^0 + He^{2+} + e^-$ by solving a time-dependent Schr\\"odinger equation (TDSE) under the classical projectile motion approximation in one-dimensional kinematics. In addition, we construct various time independent analogues of our model using lowest order perturbation theory in the form of the Born series. By comparing various aspects of the TDSE and the Born series calculations, we conclude that the recent discrepancies of experimental and theoretical data may be attributed to deficiency of the Born models used by other authors. We demonstrate that the correct Born series for TI should include the momentum space overlap between the double ionization amplitude and the wave function of the transferred electron.
The dusty MOCASSIN: fully self-consistent 3D photoionisation and dust radiative transfer models
B. Ercolano; M. J. Barlow; P. J. Storey
2005-07-02T23:59:59.000Z
We present the first 3D Monte Carlo (MC) photoionisation code to include a fully self-consistent treatment of dust radiative transfer (RT) within a photoionised region. This is the latest development (Version 2.0) of the gas-only photoionisation code MOCASSIN (Ercolano et al., 2003a), and employs a stochastic approach to the transport of radiation, allowing both the primary and secondary components of the radiation field to be treated self-consistently, whilst accounting for the scattering of radiation by dust grains mixed with the gas, as well as the absorption and emission of radiation by both the gas and the dust components. A set of rigorous benchmark tests have been carried out for dust-only spherically symmetric geometries and 2D disk configurations. MOCASSIN's results are found to be in agreement with those obtained by well established dust-only RT codes that employ various approaches to the solution of the RT problem. A model of the dust and of the photoionised gas components of the planetary nebula (PN) NGC 3918 is also presented as a means of testing the correct functioning of the RT procedures in a case where both gas and dust opacities are present. The two components are coupled via the heating of dust grains by the absorption of both UV continuum photons and resonance line photons emitted by the gas. The MOCASSIN results show agreement with those of a 1D dust and gas model of this nebula published previously, showing the reliability of the new code, which can be applied to a variety of astrophysical environments.
Development of a coupling code for PWR reactor cavity radiation streaming calculation
Zheng, Z.; Wu, H.; Cao, L.; Zheng, Y.; Zhang, H.; Wang, M. [NECP Laboratory, School of Nuclear Science and Technology, Xi'an Jiaotong Univ., Xi'an Shaanxi 710049 (China)
2012-07-01T23:59:59.000Z
PWR reactor cavity radiation streaming is important for the safe of the personnel and equipment, thus calculation has to be performed to evaluate the neutron flux distribution around the reactor. For this calculation, the deterministic codes have difficulties in fine geometrical modeling and need huge computer resource; and the Monte Carlo codes require very long sampling time to obtain results with acceptable precision. Therefore, a coupling method has been developed to eliminate the two problems mentioned above in each code. In this study, we develop a coupling code named DORT2MCNP to link the Sn code DORT and Monte Carlo code MCNP. DORT2MCNP is used to produce a combined surface source containing top, bottom and side surface simultaneously. Because SDEF card is unsuitable for the combined surface source, we modify the SOURCE subroutine of MCNP and compile MCNP for this application. Numerical results demonstrate the correctness of the coupling code DORT2MCNP and show reasonable agreement between the coupling method and the other two codes (DORT and MCNP). (authors)
MicroShield analysis to calculate external radiation dose rates for several spent fuel casks
Marincel, M.K. [Missouri Univ., Rolla, MO (United States); Weiner, R.F.; Osborn, D.M. [Sandia National Laboratories, Albuquerque, NM (United States)
2007-07-01T23:59:59.000Z
The purpose of this MicroShield analysis is to calculate the external radiation, primarily gamma, dose rate for spent fuel casks. The reason for making this calculation is that currently all analyses of transportation risk assume that this external dose rate is the maximum allowed by regulation, 10 mrem/hr at 2 m from the casks, and the risks of incident-free transportation are thus always overestimated to an unknown extent. In order to do this, the program by Grove Software, MicroShield 7.01, was used to model three Nuclear Regulatory Commission (NRC) approved casks: HI-STAR 100, GA-4, and NAC-STC, loaded with specific source material. Dimensions were obtained from NUREG/CR-6672 and the Certificates of Compliance for each respective cask. Detectors were placed at the axial point at 1 m and 2 m from the outer gamma shielding of the casks. In the April 8, 2004 publication of the Federal Register, a notice of intent to prepare a Supplemental Yucca Mountain Environmental Impact Statement (DOE/EIS-0250F-S1) was published by the Office of Civilian Radioactive Waste Management (OCRWM) in order to consider design, construction, operation, and transportation of spent nuclear fuel to the Yucca Mountain repository [1]. These more accurate estimates of the external dose rates could be used in order to provide a more risk-informed analysis. (authors)
Chen, Z. F.; Reading, John F.
1993-01-01T23:59:59.000Z
by Wilets and Gallaher. The discrepancy may be attributed to the inaccuracy in numerical calcula- tion. These two-centered expansions (TCE) consume much computing time. Reading, Ford, and Becker [23?25] have invented a set of one... ranges have been extended from 100 keV in previous work to 250 keV. The charge-transfer cross sections to the 2p state fit the experimental data at 30 keV and are almost the same as those calculated using TCE method by Cheshire and Shakeshaft...
Chadima, Pavel; Harmanec, Petr; Wolf, Marek [Astronomical Institute of the Charles University, Faculty of Mathematics and Physics, V Holesovickach 2, CZ-180 00 Praha 8 (Czech Republic); Firt, Roman [Mathematical Institute, University of Bayreuth, D-95447 Bayreuth (Germany); Ruzdjak, Domagoj; Bozic, Hrvoje [Hvar Observatory, Faculty of Geodesy, University of Zagreb, 10000 Zagreb (Croatia); Koubsky, Pavel, E-mail: pavel.chadima@gmail.com [Astronomical Institute of the Academy of Sciences, CZ-251 65 Ondrejov (Czech Republic)
2011-07-15T23:59:59.000Z
H{alpha} emission V/R variations caused by discontinuous mass transfer in interacting binaries with a rapidly rotating accreting star are modeled qualitatively for the first time. The program ZEUS-MP was used to create a non-linear three-dimensional hydrodynamical model of a development of a blob of gaseous material injected into an orbit around a star. It resulted in the formation of an elongated disk with a slow prograde revolution. The LTE radiative transfer program SHELLSPEC was used to calculate the H{alpha} profiles originating in the disk for several phases of its revolution. The profiles have the form of a double emission and exhibit V/R and radial velocity variations. However, these variations should be a temporal phenomenon since imposing a viscosity in the given model would lead to a circularization of the disk and fading-out of the given variations.
Fragment transition density method to calculate electronic coupling for excitation energy transfer
Voityuk, Alexander A., E-mail: alexander.voityuk@icrea.cat [Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain and Institut de Química Computacional i Catàlisi (IQCC), Universitat de Girona 17071 Girona (Spain)
2014-06-28T23:59:59.000Z
A general approach, the Fragment Transition Density (FTD) scheme, is introduced to estimate electronic coupling for excitation energy transfer in a molecular system. Within this method, the excitation energies and transition densities of the system are used to derive the coupling matrix element. The scheme allows one to treat systems where exciton donor and acceptor are close together and their exchange interaction and orbital overlap are significant. The FTD method can be applied in combination with any quantum mechanical approach to treat excited states of general nature including single-, double-, and higher excitations. Using FTD approach, we derive excitonic couplings for several systems computed with the CIS, TD DFT and MS-CASPT2 methods. In particular, it is shown that the estimated coupling values in DNA ?-stacks are strongly affected by the short-range electronic interaction of adjacent nucleobases.
Rudenko, V. V. [Russian Federation Ministry of Defense, 12th Central Scientific Research Institute (Russian Federation)
2010-12-15T23:59:59.000Z
The problem of laser deposition with allowance for thermal radiation transport inside and outside the laser torch is considered in a multigroup approximation. The energy fluxes of laser torch thermal radiation onto a target in the far and near zones are calculated as functions of time and the character of the exposure. It is shown that absorption of thermal fluxes in the substrate and target in the course of laser deposition results in their substantial heating. The possibility of diagnosing thermal radiation fluxes from the laser torch by using photodetectors is demonstrated.
A new nonlocal thermodynamical equilibrium radiative transfer method for cool stars
Lambert, Julien; Ryde, Nils; Faure, Alexandre
2015-01-01T23:59:59.000Z
Context: The solution of the nonlocal thermodynamical equilibrium (non-LTE) radiative transfer equation usually relies on stationary iterative methods, which may falsely converge in some cases. Furthermore, these methods are often unable to handle large-scale systems, such as molecular spectra emerging from, for example, cool stellar atmospheres. Aims: Our objective is to develop a new method, which aims to circumvent these problems, using nonstationary numerical techniques and taking advantage of parallel computers. Methods: The technique we develop may be seen as a generalization of the coupled escape probability method. It solves the statistical equilibrium equations in all layers of a discretized model simultaneously. The numerical scheme adopted is based on the generalized minimum residual method. Result:. The code has already been applied to the special case of the water spectrum in a red supergiant stellar atmosphere. This demonstrates the fast convergence of this method, and opens the way to a wide va...
A Realizability-Preserving Discontinuous Galerkin Method for the $M_1$ Model of Radiative Transfer
Frank, Martin [RWTH Aachen University; Olbrant, Edgar [RWTH Aachen University; Hauck, Cory D [ORNL
2012-01-01T23:59:59.000Z
The M{sub 1} model for radiative transfer coupled to a material energy equation in planar geometry is studied in this paper. For this model to be well-posed, its moment variables must fulfill certain realizability conditions. Our main focus is the design and implementation of an explicit Runge-Kutta discontinuous Galerkin method which, under a more restrictive CFL condition, guarantees the realizability of the moment variables and the positivity of the material temperature. An analytical proof for our realizability-preserving scheme, which also includes a slope-limiting technique, is provided and confirmed by various numerical examples. Among other things, we present accuracy tests showing convergence up to fourth-order, compare our results with an analytical solution in a Riemann problem, and consider a Marshak wave problem.
Jiri Stepan; Petr Heinzel; Sylvie Sahal-Brechot
2007-01-22T23:59:59.000Z
Context. We present a theoretical review of the effect of impact polarization of a hydrogen H$\\alpha$ line due to an expected proton beam bombardment in solar flares. Aims. Several observations indicate the presence of the linear polarization of the hydrogen H$\\alpha$ line observed near the solar limb above 5% and preferentially in the radial direction. We theoretically review the problem of deceleration of the beam originating in the coronal reconnection site due to its interaction with the chromospheric plasma, and describe the formalism of the density matrix used in our description of the atomic processes and the treatment of collisional rates. Methods. We solve the self-consistent NLTE radiation transfer problem for the particular semiempirical chromosphere models for both intensity and linear polarization components of the radiation field. Results. In contrast to recent calculations, our results show that the energy distribution of the proton beam at H$\\alpha$ formation levels and depolarizing collisions by background electrons and protons cause a significant reduction of the effect below 0.1%. The radiation transfer solution shows that tangential resonance-scattering polarization dominates over the impact polarization effect in all considered models. Conclusions. In the models studied, proton beams are unlikely to be a satisfying explanation for the observed linear polarization of the H$\\alpha$ line.
Xie, Weiwei; Xu, Yang; Zhu, Lili; Shi, Qiang, E-mail: qshi@iccas.ac.cn [Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100190 (China)] [Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100190 (China)
2014-05-07T23:59:59.000Z
We present mixed quantum classical calculations of the proton transfer (PT) reaction rates represented by a double well system coupled to a dissipative bath. The rate constants are calculated within the so called nontraditional view of the PT reaction, where the proton motion is quantized and the solvent polarization is used as the reaction coordinate. Quantization of the proton degree of freedom results in a problem of non-adiabatic dynamics. By employing the reactive flux formulation of the rate constant, the initial sampling starts from the transition state defined using the collective reaction coordinate. Dynamics of the collective reaction coordinate is treated classically as over damped diffusive motion, for which the equation of motion can be derived using the path integral, or the mixed quantum classical Liouville equation methods. The calculated mixed quantum classical rate constants agree well with the results from the numerically exact hierarchical equation of motion approach for a broad range of model parameters. Moreover, we are able to obtain contributions from each vibrational state to the total reaction rate, which helps to understand the reaction mechanism from the deep tunneling to over the barrier regimes. The numerical results are also compared with those from existing approximate theories based on calculations of the non-adiabatic transmission coefficients. It is found that the two-surface Landau-Zener formula works well in calculating the transmission coefficients in the deep tunneling regime, where the crossing point between the two lowest vibrational states dominates the total reaction rate. When multiple vibrational levels are involved, including additional crossing points on the free energy surfaces is important to obtain the correct reaction rate using the Landau-Zener formula.
Constraints on Blazar Jet Conditions During Gamma-Ray Flaring from Radiative Transfer Modeling
Aller, Margo F; Aller, Hugh D; Hovatta, Talvikki
2013-01-01T23:59:59.000Z
As part of a program to investigate jet flow conditions during GeV gamma-ray flares detected by Fermi, we are using UMRAO multi-frequency, centimeter-band total flux density and linear polarization monitoring observations to constrain radiative transfer models incorporating propagating shocks orientated at an arbitrary angle to the flow direction. We describe the characteristics of the model, illustrate how the data are used to constrain the models, and present results for three program sources with diverse characteristics: PKS 0420-01, OJ 287, and 1156+295. The modeling of the observed spectral behavior yields information on the sense, strength and orientation of the shocks producing the radio-band flaring; on the energy distribution of the radiating particles; and on the observer's viewing angle with respect to the jet independent of VLBI data. We present evidence that, while a random component dominates the jet magnetic field, a distinguishing feature of those radio events with an associated gamma-ray flar...
An Analytical Model of Radiation-Induced Charge Transfer Inefficiency for CCD Detectors
Short, Alexander; de Bruijne, Jos H J; Prod'homme, Thibaut
2013-01-01T23:59:59.000Z
The European Space Agency's Gaia mission is scheduled for launch in 2013. It will operate at L2 for 5 years, rotating slowly to scan the sky so that its two optical telescopes will repeatedly observe more than one billion stars. The resulting data set will be iteratively reduced to solve for the position, parallax and proper motion of every observed star. The focal plane contains 106 large area silicon CCDs continuously operating in a mode where the line transfer rate and the satellite rotation are in synchronisation. One of the greatest challenges facing the mission is radiation damage to the CCDs which will cause charge deferral and image shape distortion. This is particularly important because of the extreme accuracy requirements of the mission. Despite steps taken at hardware level to minimise the effects of radiation, the residual distortion will need to be calibrated during the pipeline data processing. Due to the volume and inhomogeneity of data involved, this requires a model which describes the effec...
Baum, Bryan A.
, a parameterization of the bulk scattering properties is developed. The radiative properties of ice cloudsSpectral signature of ice clouds in the far-infrared region: Single-scattering calculations the spectral signature of ice clouds in the far-infrared (far-IR) spectral region from 100 to 667 cmÃ?1 (15
Borodkin, P.G.; Borodkin, G.I.; Khrennikov, N.N. [Scientific and Engineering Centre for Nuclear and Radiation Safety SEC NRS, Building 5, Malaya Krasnoselskaya Street, 2/8, 107140 Moscow (Russian Federation)
2011-07-01T23:59:59.000Z
The approach of improved uncertainty-accounted conservative evaluation of vodo-vodyanoi energetichesky reactor (VVER) (reactor-) pressure-vessel (RPV) radiation loading parameters has been proposed. This approach is based on the calculational-experimental procedure, which takes into account C/E ratio, depending on over- or underestimation, and uncertainties of measured and calculated results. An application of elaborated approach to the full-scale ex-vessel neutron dosimetry experiments on Russian VVERs combined with neutron-transport calculations has been demonstrated in the paper. (authors)
Improved method for calculating the radiation heat generation in the BOR-60 reactor
Varivtsev, A. V., E-mail: vav3@niiar.ru; Zhemkov, I. Yu. [JSC “SSC RIAR,” Dimitrovgrad-10 (Russian Federation)
2014-12-15T23:59:59.000Z
The results of theoretical and experimental studies aimed at determining the radiation heat generation in the BOR-60 reactor reveal the drawbacks of the computational methods used at present. An algorithm that is free from these drawbacks and allows one to determine the radiation heat generation computationally is proposed.
Building wall heat flux calculations
Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.
1987-01-01T23:59:59.000Z
Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall.
Ly{alpha} RADIATIVE TRANSFER IN COSMOLOGICAL SIMULATIONS USING ADAPTIVE MESH REFINEMENT
Laursen, Peter [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100, Copenhagen Oe (Denmark); Razoumov, Alexei O. [Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Mary's University, Halifax, NS, B3H3C3 (Canada); Sommer-Larsen, Jesper [Excellence Cluster Universe, Technische Universitaet Muenchen, Boltzmannstrasse 2, D-85748 Garching (Germany)], E-mail: pela@dark-cosmology.dk, E-mail: razoumov@ap.smu.ca, E-mail: jslarsen@astro.ku.dk
2009-05-01T23:59:59.000Z
A numerical code for solving various Ly{alpha} radiative transfer (RT) problems is presented. The code is suitable for an arbitrary, three-dimensional distribution of Ly{alpha} emissivity, gas temperature, density, and velocity field. Capable of handling Ly{alpha} RT in an adaptively refined grid-based structure, it enables detailed investigation of the effects of clumpiness of the interstellar (or intergalactic) medium. The code is tested against various geometrically and physically idealized configurations for which analytical solutions exist, and subsequently applied to three different simulated high-resolution 'Lyman-break galaxies', extracted from high-resolution cosmological simulations at redshift z = 3.6. Proper treatment of the Ly{alpha} scattering reveals a diversity of surface brightness (SB) and line profiles. Specifically, for a given galaxy the maximum observed SB can vary by an order of magnitude, and the total flux by a factor of 3-6, depending on the viewing angle. This may provide an explanation for differences in observed properties of high-redshift galaxies, and in particular a possible physical link between Lyman-break galaxies and regular Ly{alpha} emitters.
Hillen, M; Menu, J; Van Winckel, H; Min, M; Mulders, G D
2015-01-01T23:59:59.000Z
We aim to constrain the structure of the circumstellar material around the post-AGB binary and RV Tauri pulsator AC Her. We want to constrain the spatial distribution of the amorphous as well as of the crystalline dust. We present very high-quality mid-IR interferometric data that were obtained with MIDI/VLTI. We analyse the MIDI data and the full SED, using the MCMax radiative transfer code, to find a good structure model of AC Her's circumbinary disk. We include a grain size distribution and midplane settling of dust self-consistently. The spatial distribution of crystalline forsterite in the disk is investigated with the mid-IR features, the 69~$\\mu$m band and the 11.3~$\\mu$m signatures in the interferometric data. All the data are well fitted. The inclination and position angle of the disk are well determined at i=50+-8 and PA=305+-10. We firmly establish that the inner disk radius is about an order of magnitude larger than the dust sublimation radius. Significant grain growth has occurred, with mm-sized ...
Temperature-extrapolation method for Implicit Monte Carlo - Radiation hydrodynamics calculations
McClarren, R. G. [Department of Nuclear Engineering, Texas A and M University, 3133 TAMU, College Station, TX 77802 (United States); Urbatsch, T. J. [XTD-5: Air Force Systems, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 77845 (United States)
2013-07-01T23:59:59.000Z
We present a method for implementing temperature extrapolation in Implicit Monte Carlo solutions to radiation hydrodynamics problems. The method is based on a BDF-2 type integration to estimate a change in material temperature over a time step. We present results for radiation only problems in an infinite medium and for a 2-D Cartesian hohlraum problem. Additionally, radiation hydrodynamics simulations are presented for an RZ hohlraum problem and a related 3D problem. Our results indicate that improvements in noise and general behavior are possible. We present considerations for future investigations and implementations. (authors)
Gritzo, L.A.; Skocypec, R.D. [Sandia National Labs., Albuquerque, NM (United States); Tong, T.W. [Arizona State Univ., Tempe, AZ (United States). Dept. of Mechanical and Aerospace Engineering
1995-01-11T23:59:59.000Z
Radiation in participating media is an important transport mechanism in many physical systems. The simulation of complex radiative transfer has not effectively exploited high-performance computing capabilities. In response to this need, a workshop attended by members active in the high-performance computing community, members active in the radiative transfer community, and members from closely related fields was held to identify how high-performance computing can be used effectively to solve the transport equation and advance the state-of-the-art in simulating radiative heat transfer. This workshop was held on March 29-30, 1994 in Albuquerque, New Mexico and was conducted by Sandia National Laboratories. The objectives of this workshop were to provide a vehicle to stimulate interest and new research directions within the two communities to exploit the advantages of high-performance computing for solving complex radiative heat transfer problems that are otherwise intractable.
Efficient weakly-radiative wireless energy transfer: An EIT-like approach
Soljaèiæ, Marin
coupling on which witricity-type wireless energy transfer is based. We show that in certain parameter
McCauley, Alexander P; Krüger, Matthias; Johnson, Steven G
2011-01-01T23:59:59.000Z
We examine the non-equilibrium radiative heat transfer between a plate and finite cylinders and cones, making the first accurate theoretical predictions for the total heat transfer and the spatial heat flux profile for three-dimensional compact objects including corners or tips. We find qualitatively different scaling laws for conical shapes at small separations, and in contrast to a flat/slightly-curved object, a sharp cone exhibits a local \\emph{minimum} in the spatially resolved heat flux directly below the tip. The method we develop, in which a scattering-theory formulation of thermal transfer is combined with a boundary-element method for computing scattering matrices, can be applied to three-dimensional objects of arbitrary shape.
Diesel Cycle: Since we use a Closed System, the work and heat transfers are calculated from changes of Diesels (and therefore potential th) are likely to be much higher, because rather than worrying about pre-ignition, we are counting on self-ignition! 1 #12;On top of that, Diesel cycles have no throttling losses, so
A revised model of the kidney for medical internal radiation dose calculations
Patel, Jyoti Shivabhai
1988-01-01T23:59:59.000Z
are frequently the organs receiving the highest level of radioactivity and, therefore, the largest radiation dose. Short lived radiopharmaceuticals, that are now injected in millicurie quantities in nuclear medicine for rapid-sequence imaging of the brain... radionuclides (Appendix B). 17 These include the following radionuclides presently used in nuclear medicine: P-32, Cr-51, Co-57, Ga-67, Tc-99m, In-ill, I-123, Xe-127, I-131, Xe-133, and T1-201. If the radionuclide emits penetrating radiation, the code...
Moncada-Villa, Edwin; Garcia-Vidal, Francisco J; Garcia-Martin, Antonio; Cuevas, Juan Carlos
2015-01-01T23:59:59.000Z
We present a comprehensive theoretical study of the magnetic field dependence of the near-field radiative heat transfer (NFRHT) between two parallel plates. We show that when the plates are made of doped semiconductors, the near-field thermal radiation can be severely affected by the application of a static magnetic field. We find that irrespective of its direction, the presence of a magnetic field reduces the radiative heat conductance, and dramatic reductions up to 700% can be found with fields of about 6 T at room temperature. We show that this striking behavior is due to the fact that the magnetic field radically changes the nature of the NFRHT. The field not only affects the electromagnetic surface waves (both plasmons and phonon polaritons) that normally dominate the near-field radiation in doped semiconductors, but it also induces hyperbolic modes that progressively dominate the heat transfer as the field increases. In particular, we show that when the field is perpendicular to the plates, the semicond...
Comparison of different global information sources used in surface radiative flux calculation
), the Laboratoire de MeÂ´teÂ´orologie Dynamique, NOAA/NASA Pathfinder Advanced Very High Resolution Radiometer project Spectroradiometer product, the NASA Global Energy and Water Cycle Experiment Surface Radiation Budget project surface albedos in the near-infrared remain poorly constrained (highly uncertain), they do not cause too
Frankel, J.I.
1997-09-01T23:59:59.000Z
This investigation used sysmbolic manipulation in developing analytical methods and general computational strategies for solving both linear and nonlinear, regular and singular integral and integro-differential equations which appear in radiative and mixed-mode energy transport. Contained in this report are seven papers which present the technical results as individual modules.
LR Greenwood
1999-06-17T23:59:59.000Z
The Fusion Breeder Reactor (FUBR) and Breeder Exchange Matrix (BEATRIX) experiments were cooperative efforts by members of the International Energy Agency to investigate the irradiation behavior of solid breeder materials for tritium production to support future fusion reactors. Lithium ceramic materials including Li{sub 2}O, LiAlO{sub 2}, Li{sub 4}SiO{sub 4}, and Li{sub 2}ZrO{sub 3} with varying {sup 6}Li enrichments from 0 to 95% were irradiated in a series of experiments in the Experimental Breeder Reactor (EBR II) and in the Fast Flux Test Facility (FFTF) over a period of about 10 years from 1982 to 1992. These experiments were characterized in terms of the nominal fast neutron fluences and measured {sup 6}Li burnup factors, as determined by either mass spectrometry or helium measurements. Radiation damage in these compounds is caused by both the {sup 6}Li-burnup reaction and by all other possible neutron reactions with the atoms in the compound materials. In this report, displacements per atom (dpa) values have been calculated for each type of material in each of the various irradiations that were conducted. Values up to 11% {sup 6}Li-burnup and 130 dpa are predicted for the longest irradiations. The dpa cross sections were calculated for each compound using the SPECOMP computer code. Details of the dpa calculations are presented in the report. Total dpa factors were determined with the SPECTER computer code by averaging the dpa cross sections over the measured or calculated neutron flux spectra for each series of irradiations. Using these new calculations, previously measured radiation damage effects in these lithium compounds can be compared or correlated with other irradiation data on the basis of the dpa factor as well as {sup 6}Li-burnup.
D'Angelo, Gennaro
2013-01-01T23:59:59.000Z
We perform global three-dimensional (3-D) radiation-hydrodynamics calculations of the envelopes surrounding young planetary cores of 5, 10, and 15 Earth masses, located in a protoplanetary disk at 5 and 10 AU from a solar-mass star. We apply a nested-grid technique to resolve the thermodynamics of the disk at the orbital-radius length scale and that of the envelope at the core-radius length scale. The gas is modeled as a solar mixture of molecular and atomic hydrogen, helium, and their ions. The equation of state accounts for both gas and radiation, and gas energy includes contributions from rotational and vibrational states of molecular hydrogen and from ionization of atomic species. Dust opacities are computed from first principles, applying the full Mie theory. One-dimensional (1-D) calculations of planet formation are used to supplement the 3-D calculations by providing energy deposition rates in the envelope due to solids accretion. We compare 1-D and 3-D envelopes and find that masses and gas accretion ...
Building wall heat flux calculations
Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.
1987-06-01T23:59:59.000Z
Calculations of the heat transfer through the standard stud wall structure of a residential building are described. The wall cavity contains no insulation. Four of the five test cases represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using the Implicit Compressible Eulerian (ICE) algorithm. The fluid flow calculation is coupled to the radiation-conduction model for the solid portions of the system. Conduction through sill plates is about 4% of the total heat transferred through a composite wall. All of the other model elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.
Kubas, Adam; Blumberger, Jochen, E-mail: j.blumberger@ucl.ac.uk [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)] [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Hoffmann, Felix [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom) [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, Universitätsstr. 150, 44801 Bochum (Germany); Heck, Alexander; Elstner, Marcus [Institute of Physical Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, 76131 Karlsruhe (Germany)] [Institute of Physical Chemistry, Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, 76131 Karlsruhe (Germany); Oberhofer, Harald [Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747 Garching (Germany)] [Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85747 Garching (Germany)
2014-03-14T23:59:59.000Z
We introduce a database (HAB11) of electronic coupling matrix elements (H{sub ab}) for electron transfer in 11 ?-conjugated organic homo-dimer cations. High-level ab inito calculations at the multireference configuration interaction MRCI+Q level of theory, n-electron valence state perturbation theory NEVPT2, and (spin-component scaled) approximate coupled cluster model (SCS)-CC2 are reported for this database to assess the performance of three DFT methods of decreasing computational cost, including constrained density functional theory (CDFT), fragment-orbital DFT (FODFT), and self-consistent charge density functional tight-binding (FODFTB). We find that the CDFT approach in combination with a modified PBE functional containing 50% Hartree-Fock exchange gives best results for absolute H{sub ab} values (mean relative unsigned error = 5.3%) and exponential distance decay constants ? (4.3%). CDFT in combination with pure PBE overestimates couplings by 38.7% due to a too diffuse excess charge distribution, whereas the economic FODFT and highly cost-effective FODFTB methods underestimate couplings by 37.6% and 42.4%, respectively, due to neglect of interaction between donor and acceptor. The errors are systematic, however, and can be significantly reduced by applying a uniform scaling factor for each method. Applications to dimers outside the database, specifically rotated thiophene dimers and larger acenes up to pentacene, suggests that the same scaling procedure significantly improves the FODFT and FODFTB results for larger ?-conjugated systems relevant to organic semiconductors and DNA.
Effective field theory calculation of nd radiative capture at thermal energies
H. Sadeghi; S. Bayegan; Harald W. Griesshammer
2006-12-03T23:59:59.000Z
The cross section for the thermal neutron capture by the deuteron is calculated with pionless Effective Field Theory(EFT). No new Three-Nucleon forces are needed up to next-to-next-to-leading order in order to achieve cut-off independent results, besides those fixed by the triton binding energy and Nd scattering length in the triton channel. The cross-section is accurately determined to be $\\sigma_{tot}=[0.503\\pm 0.003]mb$. At zero energies, the magnetic $M1$-transition gives the dominant contribution and is calculated up to next-to-next-to-leading order (N$^2$LO). Close agreement between the available experimental data and the calculated cross section is reached. We demonstrate convergence and cutoff independence order by order in the low-energy expansion.
Carney, J.H.; DeAngelis, D.L.; Gardner, R.H.; Mankin, J.B.; Post, W.M.
1981-02-01T23:59:59.000Z
Six indices are presented for linear compartment systems that quantify the probable pathways of matter or energy transfer, the likelihood of recurrence if the model contains feedback loops, and the number of steps (transfers) through the system. General examples are used to illustrate how these indices can simplify the comparison of complex systems or organisms in unrelated systems.
Benjamin Seibold; Martin Frank
2014-06-12T23:59:59.000Z
We present a simple method to solve spherical harmonics moment systems, such as the the time-dependent $P_N$ and $SP_N$ equations, of radiative transfer. The method, which works for arbitrary moment order $N$, makes use of the specific coupling between the moments in the $P_N$ equations. This coupling naturally induces staggered grids in space and time, which in turn give rise to a canonical, second-order accurate finite difference scheme. While the scheme does not possess TVD or realizability limiters, its simplicity allows for a very efficient implementation in Matlab. We present several test cases, some of which demonstrate that the code solves problems with ten million degrees of freedom in space, angle, and time within a few seconds. The code for the numerical scheme, called StaRMAP (Staggered grid Radiation Moment Approximation), along with files for all presented test cases, can be downloaded so that all results can be reproduced by the reader.
A. Avdeenkov; S. Goriely; S. Kamerdzhiev; S. Krewald
2011-08-08T23:59:59.000Z
The E1 strength function for 15 stable and unstable Sn even-even isotopes from A=100 till A=176 are calculated using the self-consistent microscopic theory which, in addition to the standard (Q)RPA approach, takes into account the single-particle continuum and the phonon coupling. Our analysis shows two distinct regions for which the integral characteristics of both the giant and pygmy resonances behave rather differently. For neutron-rich nuclei, starting from $^{132}$Sn, we obtain a giant E1 resonance which significantly deviates from the widely-used systematics extrapolated from experimental data in the $\\beta$-stability valley. We show that the inclusion of the phonon coupling is necessary for a proper description of the low-energy pygmy resonances and the corresponding transition densities for $A132$ region the influence of phonon coupling is significantly smaller. The radiative neutron capture cross sections leading to the stable $^{124}$Sn and unstable $^{132}$Sn and $^{150}$Sn nuclei are calculated with both the (Q)RPA and the beyond-(Q)RPA strength functions and shown to be sensitive to both the predicted low-lying strength and the phonon coupling contribution. The comparison with the widely-used phenomenological Generalized Lorentzian approach shows considerable differences both for the strength function and the radiative neutron capture cross section. In particular, for the neutron-rich $^{150}$Sn, the reaction cross section is found to be increased by a factor greater than 20. We conclude that the present approach may provide a complete and coherent description of the $\\gamma$-ray strength function for astrophysics applications. In particular, such calculations are highly recommended for a reliable estimate of the electromagnetic properties of exotic nuclei.
HEAT AND MOISTURE TRANSFER THROUGH CLOTHING
Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie
2009-01-01T23:59:59.000Z
R. C. Eberhart (ed), Heat transfer in medicine and biology.between convective heat transfer and mass transferConvective and radiative heat transfer coefficients for
Heat and moisture transfer through clothing
Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie
2009-01-01T23:59:59.000Z
R. C. Eberhart (ed), Heat transfer in medicine and biology.Convective and radiative heat transfer coefficients forbetween convective heat transfer and mass transfer
Clementel, Nicola; Kruip, Chael J H; Paardekooper, Jan-Pieter
2015-01-01T23:59:59.000Z
Spectral observations of the massive colliding wind binary Eta Carinae show phase-dependent variations, in intensity and velocity, of numerous helium emission and absorption lines throughout the entire 5.54-year orbit. Approaching periastron, the 3D structure of the wind-wind interaction region (WWIR) gets highly distorted due to the eccentric ($e \\sim 0.9$) binary orbit. The secondary star ($\\eta_{\\mathrm{B}}$) at these phases is located deep within the primary's dense wind photosphere. The combination of these effects is thought to be the cause of the particularly interesting features observed in the helium lines at periastron. We perform 3D radiative transfer simulations of $\\eta$ Car's interacting winds at periastron. Using the SimpleX radiative transfer algorithm, we post-process output from 3D smoothed particle hydrodynamic simulations of the inner 150 au of the $\\eta$ Car system for two different primary star mass-loss rates ($\\dot{M}_{\\eta_{\\mathrm{A}}}$). Using previous results from simulations at ap...
Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)
2010-12-15T23:59:59.000Z
This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)
Gan, Li, E-mail: ligan0001@gmail.com; Mousen, Cheng; Xiaokang, Li [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)] [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)
2014-03-15T23:59:59.000Z
In the laser intensity range that the laser supported detonation (LSD) wave can be maintained, dissociation, ionization and radiation take a substantial part of the incidence laser energy. There is little treatment on the phenomenon in the existing models, which brings obvious discrepancies between their predictions and the experiment results. Taking into account the impact of dissociation, ionization and radiation in the conservations of mass, momentum and energy, a modified LSD wave model is developed which fits the experimental data more effectively rather than the existing models. Taking into consideration the pressure decay of the normal and the radial rarefaction, the laser induced impulse that is delivered to the target surface is calculated in the air; and the dependencies of impulse performance on laser intensity, pulse width, ambient pressure and spot size are indicated. The results confirm that the dissociation is the pivotal factor of the appearance of the momentum coupling coefficient extremum. This study focuses on a more thorough understanding of LSD and the interaction between laser and matter.
Napier, B.A.; Roswell, R.L.; Kennedy, W.E. Jr.; Strenge, D.L.
1980-06-01T23:59:59.000Z
The computer programs ARRRG and FOOD were written to facilitate the calculation of internal radiation doses to man from the radionuclides in the environment and external radiation doses from radionuclides in the environment. Using ARRRG, radiation doses to man may be calculated for radionuclides released to bodies of water from which people might obtain fish, other aquatic foods, or drinking water, and in which they might fish, swim or boat. With the FOOD program, radiation doses to man may be calculated from deposition on farm or garden soil and crops during either an atmospheric or water release of radionuclides. Deposition may be either directly from the air or from irrigation water. Fifteen crop or animal product pathways may be chosen. ARRAG and FOOD doses may be calculated for either a maximum-exposed individual or for a population group. Doses calculated are a one-year dose and a committed dose from one year of exposure. The exposure is usually considered as chronic; however, equations are included to calculate dose and dose commitment from acute (one-time) exposure. The equations for calculating internal dose and dose commitment are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and Maximum Permissible Concentration (MPC) of each radionuclide. The radiation doses from external exposure to contaminated farm fields or shorelines are calculated assuming an infinite flat plane source of radionuclides. A factor of two is included for surface roughness. A modifying factor to compensate for finite extent is included in the shoreline calculations.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Lee, W.-L.; Gu, Y.; Liou, K. N.; Leung, L. R.; Hsu, H.-H.
2014-01-01T23:59:59.000Z
We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the Western United States, specifically the Rocky Mountains and Sierra Nevada using CCSM4 (CAM4/CLM4) global model with a 0.23° × 0.31° resolution for simulations over 6 years. In 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation [3-D ? PP (plane-parallel)] adjustment to ensure that energy balance at the surface is conserved in global climate simulations based on 3-D radiation parameterization.more »We show that deviations of the net surface fluxes are not only affected by 3-D mountains, but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while decreases for higher elevations with a minimum in April. Liquid runoff significantly decreases in higher elevations after April due to reduced SWE and precipitation.« less
Order Reduction of the Radiative Heat Transfer Model for the Simulation of Plasma Arcs
Fagiano, Lorenzo
2015-01-01T23:59:59.000Z
An approach to derive low-complexity models describing thermal radiation for the sake of simulating the behavior of electric arcs in switchgear systems is presented. The idea is to approximate the (high dimensional) full-order equations, modeling the propagation of the radiated intensity in space, with a model of much lower dimension, whose parameters are identified by means of nonlinear system identification techniques. The low-order model preserves the main structural aspects of the full-order one, and its parameters can be straightforwardly used in arc simulation tools based on computational fluid dynamics. In particular, the model parameters can be used together with the common approaches to resolve radiation in magnetohydrodynamic simulations, including the discrete-ordinate method, the P-N methods and photohydrodynamics. The proposed order reduction approach is able to systematically compute the partitioning of the electromagnetic spectrum in frequency bands, and the related absorption coefficients, tha...
Multigroup half space moment approximations to the radiative heat transfer equations q
Coudière, Yves
cooling) over astrophysics to combustion (e.g., in gas turbine combustion chambers). Since radiative heat into direction l 2 ½À1; 1. Furthermore, T ðx; tÞ is the material temperature. The heat conductivity is denoted with the following boundary conditions. For the material temper
Radiative transfer based scaling of LAI retrievals from reflectance data of different resolutions
Myneni, Ranga B.
is investigated with 1-km Advanced Very High Resolution Radiometer (AVHRR) data aggregated to different coarse into biogeophysical (energy and water exchanges) and biogeochemical (carbon and volatile organic compound exchanges. Vegetation leaf area index governs net radiation and its expenditure (energy balance), net primary production
Ko, Min Seok
2009-05-15T23:59:59.000Z
? =0.1, 0.2, and 0.4) and scattering albedo ( ?=0, 0.25, 0.5, 0.75 and 1). Variation of thermophysical properties with temperature was considered in this study. In this work consideration was given only to cooling. Effects of those radiative...
Solutions of the equation of radiative transfer by matrix operator techniques
Catchings, Frances Eugenia King
1973-01-01T23:59:59.000Z
angle 8 = 0'; 5. all fundamental equations can be interpreted immediately in terms of the physical interactions appropriate to the problem; 6. both upward and downward radiance can be calculated at interior points. Both the general theory... and the method of calcu- lation are discussed. Matrix operator theory is used to calculate the reflected and transmitted radiance of photons for the cases of Rayleigh scattering from a homogeneous layer and of plane parallel iv maritime haze layers...
Radiative transfer in the earth's atmosphere-ocean system using Monte Carlo techniques
Bradley, Paul Andrew
1987-01-01T23:59:59.000Z
TRANSFER PROBLEM MONTE CARLO METHOD Assumptions of the Model Photon Pathlength Emulation Techniques Sampling Scattering Functions: Angles and Probabilities Emulation of an Interface Computing the Radiance by Statistical Estimation Determination... of Direction Cosines After Scattering Flux Estimation into Detectors Determination of a New Scattering Point Photon Trajectories Direct Flux and Radiance From the Ocean Bottonr Accounting for Multiple Orders of Scattering With the Bottom Computation...
Codes for optically thick and hot photoionized media - Radiative transfer and new developments
Anne-Marie Dumont; Suzy Collin
2001-03-20T23:59:59.000Z
We describe a code designed for hot media {(T $\\ge$} a few 10$^4$ K), optically thick to Compton scattering. It computes the structure of a plane-parallel slab of gas in thermal and ionization equilibrium, illuminated on one side or on both sides by a given spectrum. This code has been presented in a previous paper (Dumont, Abrassart & Collin 2000), where several aspects were already discussed. So we focus here mainly on the recent developments. Presently the code solves the transfer of the continuum with the Accelerated Lambda Iteration method (ALI) and that of the lines in a two stream Eddington approximation, without using the local escape probability formalism to approximate the line transfer. This transfer code is coupled with a Monte Carlo code which allows to take into account direct and inverse Compton diffusions, and to compute the spectrum emitted up to MeV energies, in any geometry. The influence of a few physical parameters is shown, and the importance of the density and pressure distribution (constant density, pressure equilibrium, or hydrostatic equilibrium) is stressed. Recent improvements in the treatment of the atomic data are described, and foreseen developments are mentioned.
Heat Transfer between Graphene and Amorphous SiO2
B. N. J. Persson; H. Ueba
2010-07-22T23:59:59.000Z
We study the heat transfer between graphene and amorphous SiO2. We include both the heat transfer from the area of real contact, and between the surfaces in the non-contact region. We consider the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies, and the heat transfer by the gas in the non-contact region. We find that the dominant contribution to the heat transfer result from the area of real contact, and the calculated value of the heat transfer coefficient is in good agreement with the value deduced from experimental data.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Huang, Dong; Liu, Yangang
2014-12-01T23:59:59.000Z
Subgrid-scale variability is one of the main reasons why parameterizations are needed in large-scale models. Although some parameterizations started to address the issue of subgrid variability by introducing a subgrid probability distribution function for relevant quantities, the spatial structure has been typically ignored and thus the subgrid-scale interactions cannot be accounted for physically. Here we present a new statistical-physics-like approach whereby the spatial autocorrelation function can be used to physically capture the net effects of subgrid cloud interaction with radiation. The new approach is able to faithfully reproduce the Monte Carlo 3D simulation results with several orders less computational cost,more »allowing for more realistic representation of cloud radiation interactions in large-scale models.« less
The radiative heat transfer between a rotating nanoparticle and a plane surface
Vahid Ameri; Mehdi Shafei Aporvari; Fardin Kheirandish
2015-06-03T23:59:59.000Z
Based on a microscopic approach, we propose a Lagrangian for the combined system of a rotating dielectric nanoparticle above a plane surface in the presence of electromagnetic vacuum fluctuations. In the framework of canonical quantization, the electromagnetic vacuum field is quantized in the presence of dielectric fields describing the nanoparticle and a semi-infinite dielectric with planar interface. The radiative heat power absorbed by the rotating nanoparticle is obtained and the result is in agreement with previous results when the the rotational frequency of the nanoparticle is zero or much smaller than the relaxation frequency of the dielectrics. The well known near field effect is reexamined and discussed in terms of the rotational frequency. The radiative heat power absorbed by the nanoparticle for well-known peak frequencies, is plotted in terms of the rotational frequency showing an interesting effect resembling a phase transition around a critical frequency, determined by the relaxation frequency of the dielectrics.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Huang, Dong [Brookhaven National Laboratory (BNL), Upton, NY (United States); Liu, Yangang [Brookhaven National Laboratory (BNL), Upton, NY (United States)
2014-12-01T23:59:59.000Z
Subgrid-scale variability is one of the main reasons why parameterizations are needed in large-scale models. Although some parameterizations started to address the issue of subgrid variability by introducing a subgrid probability distribution function for relevant quantities, the spatial structure has been typically ignored and thus the subgrid-scale interactions cannot be accounted for physically. Here we present a new statistical-physics-like approach whereby the spatial autocorrelation function can be used to physically capture the net effects of subgrid cloud interaction with radiation. The new approach is able to faithfully reproduce the Monte Carlo 3D simulation results with several orders less computational cost, allowing for more realistic representation of cloud radiation interactions in large-scale models.
Mills, Peter
2012-01-01T23:59:59.000Z
Microwave emissivity models of sea ice are poorly validated empirically. Typical validation studies involve using averaged or stereotyped profiles of ice parameters against averaged radiance measurements. Measurement sites are rarely matched and even less often point-by-point. Because of saline content, complex permittivity of sea ice is highly variable and difficult to predict. Therefore, to check the validity of a typical, plane-parallel, radiative-transfer-based ice emissivity model, we apply it to fresh water ice instead of salt-water ice. Radiance simulations for lake ice are compared with measurements over Lake Superior from the Advanced Microwave Scanning Radiometer on EOS (AMSR-E). AMSR-E measurements are also collected over Antarctic icepack. For each pixel, a thermodynamic model is driven by four years of European Center for Medium Range Weather Forecasts (ECMWF) reanalysis data and the resulting temperature profiles used to drive the emissivity model. The results suggest that the relatively simple ...
Semi-Analytic Solutions to the Radiative Transfer Equations via Heterogeneous Computing
Holladay, Daniel Alphin
2014-12-10T23:59:59.000Z
to compute reaction rates for many different thermonuclear processes such as inertial confinement fusion. There are several large scale computer codes such as xRage developed at Los Alamos National Laboratory (LANL), KULL developed at Lawrence Livermore Na... spherical radiation source with A = 0.75. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 vii 1. INTRODUCTION If fusion energy is to be harnessed on earth, a thorough understanding of the regime called high energy density physics must...
Semi-Analytic Solutions to the Radiative Transfer Equations via Heterogeneous Computing
Holladay, Daniel Alphin
2014-12-10T23:59:59.000Z
to compute reaction rates for many different thermonuclear processes such as inertial confinement fusion. There are several large scale computer codes such as xRage developed at Los Alamos National Laboratory (LANL), KULL developed at Lawrence Livermore Na... spherical radiation source with A = 0.75. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 vii 1. INTRODUCTION If fusion energy is to be harnessed on earth, a thorough understanding of the regime called high energy density physics must...
Validation of the Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models
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DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Lee, W.-L.; Gu, Y.; Liou, K. N.; Leung, L. R.; Hsu, H.-H.
2015-01-01T23:59:59.000Z
We investigate 3-D mountain effects on solar flux distributions and their impact on surface hydrology over the western United States, specifically the Rocky Mountains and the Sierra Nevada, using the global CCSM4 (Community Climate System Model version 4; Community Atmosphere Model/Community Land Model – CAM4/CLM4) with a 0.23° × 0.31° resolution for simulations over 6 years. In a 3-D radiative transfer parameterization, we have updated surface topography data from a resolution of 1 km to 90 m to improve parameterization accuracy. In addition, we have also modified the upward-flux deviation (3-D–PP (plane-parallel)) adjustment to ensure that the energy balance atmore »the surface is conserved in global climate simulations based on 3-D radiation parameterization. We show that deviations in the net surface fluxes are not only affected by 3-D mountains but also influenced by feedbacks of cloud and snow in association with the long-term simulations. Deviations in sensible heat and surface temperature generally follow the patterns of net surface solar flux. The monthly snow water equivalent (SWE) deviations show an increase in lower elevations due to reduced snowmelt, leading to a reduction in cumulative runoff. Over higher-elevation areas, negative SWE deviations are found because of increased solar radiation available at the surface. Simulated precipitation increases for lower elevations, while it decreases for higher elevations, with a minimum in April. Liquid runoff significantly decreases at higher elevations after April due to reduced SWE and precipitation.« less
Jason D. Biggs; Jeffrey A. Cina
2009-10-12T23:59:59.000Z
The preceding paper describes a strategy for externally influencing the course of short-time electronic excitation transfer (EET) in molecular dimers and observing the process by nonlinear wave-packet interferometry (nl-WPI). Within a sample of isotropically oriented dimers having a specified internal geometry, a vibrational mode internal to the acceptor chromophore can be preferentially driven by electronically nonresonant impulsive stimulated Raman (or resonant infrared) excitation with a short polarized control pulse. A subsequent electronically resonant polarized pump then preferentially excites the donor, and EET ensues. Here we test both the control strategy and its spectroscopic investigation-with some sacrifice of amplitude-level detail-by calculating the pump-probe difference signal. That signal is the limiting case of the control-influenced nl-WPI signal in which the two pulses in the pump pulse-pair coincide, as do the two pulses in the probe pulse-pair. We present calculated pump-probe difference signals for (1) a model excitation-transfer complex in which two equal-energy monomers each support one moderately Franck-Condon active intramolecular vibration; (2) a simplified model of the covalent dimer dithia-anthracenophane, representing its EET dynamics following selective impulsive excitation of the weakly Franck-Condon active anthracene vibration at 385 cm-1; and (3) a model complex featuring moderate electronic-vibrational coupling in which the site energy of the acceptor chromophore is lower than that of the donor.
Schaerer, Daniel
2008-01-01T23:59:59.000Z
Using our 3D Lya radiation transfer code, we compute the radiation transfer of Lya and UV continuum photons including dust. Observational constraints on the neutral gas (column density, kinematics, etc.) are taken from other analysis of this object. RESULTS: The observed Lya profile of MS 1512--cB58 is reproduced for the first time taking radiation transfer and all observational constraints into account. The observed absorption profile is found to result naturally from the observed amount of dust and the relatively high HI column density. Radiation transfer effects and suppresion by dust transform a strong intrinsic Lya emission with EW(Lya)>~ 60 Ang into the observed faint superposed Lya emission peak. We propose that the vast majority of LBGs have intrinsically EW(Lya)~60-80 Ang or larger, and that the main physical parameter responsible for the observed variety of Lya strengths and profiles in LBGs is N_H and the accompanying variation of the dust content. Observed EW(Lya) distributions, Lya luminosity fun...
Banu, A.; Al-Abdullah, T.; Fu, C.; Gagliardi, Carl A.; McCleskey, M.; Mukhamedzhanov, A. M.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Carstoiu, F.; Burjan, V.; Kroha, V.
2009-01-01T23:59:59.000Z
The cross section of the radiative proton capture reaction on the drip line nucleus (12)N was investigated using the asymptotic normalization coefficient (ANC) method. We have used the (14)N((12)N,(13)O)(13)C proton transfer reaction at 12 Me...
Gomez, J. C.; Glatzmaier, G. C.; Mehos, M.
2012-09-01T23:59:59.000Z
The main objective of this study was to calculate the uncertainty at 95% confidence for the experimental values of heat capacity of the eutectic mixture of biphenyl/diphenyl ether (Therminol VP-1) determined from 300 to 370 degrees C. Twenty-five samples were evaluated using differential scanning calorimetry (DSC) to obtain the sample heat flow as a function of temperature. The ASTM E-1269-05 standard was used to determine the heat capacity using DSC evaluations. High-pressure crucibles were employed to contain the sample in the liquid state without vaporizing. Sample handling has a significant impact on the random uncertainty. It was determined that the fluid is difficult to handle, and a high variability of the data was produced. The heat capacity of Therminol VP-1 between 300 and 370 degrees C was measured to be equal to 0.0025T+0.8672 with an uncertainty of +/- 0.074 J/g.K (3.09%) at 95% confidence with T (temperature) in Kelvin.
Yamamoto, Takeshi; Kato, Shigeki [Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan)
2007-06-14T23:59:59.000Z
In quantum-mechanical/molecular-mechanical (QM/MM) treatment of chemical reactions in condensed phases, one solves the electronic Schroedinger equation for the solute (or an active site) under the electrostatic field from the environment. This Schroedinger equation depends parametrically on the solute nuclear coordinates R and the external electrostatic potential V. This fact suggests that one may use R and V as natural collective coordinates for describing the entire system, where V plays the role of collective solvent variables. In this paper such an (R,V) representation of the QM/MM canonical ensemble is described, with particular focus on how to treat charge transfer processes in this representation. As an example, the above method is applied to the proton-coupled electron transfer of a ubiquinol analog with phenoxyl radical in acetonitrile solvent. Ab initio free-energy surfaces are calculated as functions of R and V using the reference interaction site model self-consistent field method, the equilibrium points and the minimum free-energy crossing point are located in the (R,V) space, and then the kinetic isotope effects (KIEs) are evaluated approximately. The results suggest that a stiffer proton potential at the transition state may be responsible for unusual KIEs observed experimentally for related systems.
, Kuadasi, Turkey RAD-13-040 SPECTRAL RADIATIVE PROPERTIES OF THREE-DIMENSIONALLY ORDERED MACROPOROUS CERIA
which should be as simple as possible to be implemented in the combined heat transfer model. In general as a component of the multidimensional combined heat transfer model for soft thermal treatment of superficial
Munger, B. K.; Haberl, J. S.
2000-01-01T23:59:59.000Z
studies due several new features, including: the incorporation of an artificial horizon that prevents reflected ground radiation from striking the tilted sensors, and a routine that corrects the spectral response of photovoltaic-type sensors used...
Munger, B. K.; Haberl, J. S.
2000-01-01T23:59:59.000Z
This paper describes the development of simplified procedures for a multipyranometer array (MPA) for the continuous measurement of direct and diffuse solar radiation. The MPA described in this paper is an improvement over previously published MPA...
Jensen, R. T.; Newell, Daniel L.
1998-01-01T23:59:59.000Z
to 2.0 MW. The calculation results show the reactor to havecalculations performed by others. Core loading data and measured fhel temperatures for a Bangladesh reactor
Liu, Hongyu
Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical. (2006), Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical frequencies are calculated using the Fast-J radiative transfer algorithm. The GEOS-3 global cloud optical
Kitzmann, D; Rauer, H
2013-01-01T23:59:59.000Z
Owing to their wavelengths dependent absorption and scattering properties, clouds have a strong impact on the climate of planetary atmospheres. Especially, the potential greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the position and thus the extension of the outer boundary of the classic habitable zone around main sequence stars. We study the radiative effects of CO2 ice particles obtained by different numerical treatments to solve the radiative transfer equation. The comparison between the results of a high-order discrete ordinate method and simpler two-stream approaches reveals large deviations in terms of a potential scattering efficiency of the greenhouse effect. The two-stream methods overestimate the transmitted and reflected radiation, thereby yielding a higher scattering greenhouse effect. For the particular case of a cool M-type dwarf the CO2 ice particles show no strong effective scattering greenhouse eff...
Zhang, Zhibo
2009-05-15T23:59:59.000Z
This dissertation consists of three parts, each devoted to a particular issue of significant importance for satellite-based remote sensing of cirrus clouds. In the first part, we develop and present a fast infrared radiative transfer model...
ATS 351, Spring 2010 Energy & Radiation 60 points
Rutledge, Steven
energy per wave? Why? Shorter wavelengths carry more energy per wave. Therefore, the sun's radiationATS 351, Spring 2010 Lab #2 Energy & Radiation 60 points Please show your work for calculations Question #1: Energy (11 points) Heat is a measure of the transfer of energy from a body with a higher
Chen, Qingyan "Yan"
and airflow through a dual airflow window," Energy and Buildings, 40(4), 452-458. A computational method for calculating heat transfer and airflow through a dual-airflow window Jennifer R. Gosselin, Qingyan (Yan) Chen, and their energy performance can be studied using several computational models. A dual-airflow window with triple
Ichikawa, Takatoshi; 10.1143/JPSJ.79.074201
2010-01-01T23:59:59.000Z
We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].
Takatoshi Ichikawa; Akira Iwamoto
2010-12-20T23:59:59.000Z
We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].
Paris-Sud XI, UniversitÃ© de
al., 1998) chains leading onto the definition of a new standard in the modelling of solar radiationRemund J., Wald L., Page, J., 2003. Chain of algorithms to calculate advanced radiation parameters. Proceedings of ISES Solar World Congress, 16-19 June, Gteborg, Sweden, CD-ROM published by International Solar
Liou, K. N.; Gu, Y.; Leung, Lai-Yung R.; Lee, W- L.; Fovell, R. G.
2013-12-03T23:59:59.000Z
We investigate 3-D mountains/snow effects on solar flux distributions and their impact on surface hydrology over the western United States, specifically the Rocky Mountains and Sierra Nevada. The Weather Research and Forecasting (WRF) model, applied at a 30 km grid resolution, is used in conjunction with a 3-D radiative transfer parameterization covering a time period from 1 November 2007 to 31 May 2008, during which abundant snowfall occurred. A comparison of the 3-D WRF simulation with the observed snow water equivalent (SWE) and precipitation from Snowpack Telemetry (SNOTEL) sites shows reasonable agreement in terms of spatial patterns and daily and seasonal variability, although the simulation generally has a positive precipitation bias. We show that 3-D mountain features have a profound impact on the diurnal and monthly variation of surface radiative and heat fluxes, and on the consequent elevation dependence of snowmelt and precipitation distributions. In particular, during the winter months, large deviations (3-DPP, in which PP denotes the plane-parallel approach) of the monthly mean surface solar flux are found in the morning and afternoon hours due to shading effects for elevations below 2.5 km. During spring, positive deviations shift to the earlier morning. Over mountaintops higher than 3 km, positive deviations are found throughout the day, with the largest values of 40-60Wm?2 occurring at noon during the snowmelt season of April to May. The monthly SWE deviations averaged over the entire domain show an increase in lower elevations due to reduced snowmelt, which leads to a reduction in cumulative runoff. Over higher elevation areas, positive SWE deviations are found because of increased solar radiation available at the surface. Overall, this study shows that deviations of SWE due to 3-D radiation effects range from an increase of 18%at the lowest elevation range (1.5-2 km) to a decrease of 8% at the highest elevation range (above 3 km). Since lower elevation areas occupy larger fractions of the land surface, the net effect of 3-D radiative transfer is to extend snowmelt and snowmelt-driven runoff into the warm season. Because 60-90% of water resources originate from mountains worldwide, the aforementioned differences in simulated hydrology due solely to 3-D interactions between solar radiation and mountains/snow merit further investigation in order to understand the implications of modeling mountain water resources, and these resources’ vulnerability to climate change and air pollution.
Swihart, Mark T.
electronic structure calculation methods, being rather close in efficiency to the former due to strong simplifications in the electronic structure calculations. In the last two decades much attention has been paid of solids has become a popular and convenient tool for total energy calculations and molecular dynamics
Salah, Wa'el [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan); Department of Physics, The Hashemite University, Zarqa 13115 (Jordan); Sanchez del Rio, M. [European Synchrotron Radiation Facility, Bp 220, 38043 Grenoble Cedex (France); Hoorani, H. [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan)
2009-09-15T23:59:59.000Z
The calculation for the optics of the synchrotron radiation small and wide angle x-ray scattering beamline, currently under construction at SESAME is described. This beamline is based on a cylindrically bent germanium (111) single crystal with an asymmetric cut of 10.5 deg., followed by a 1.2 m long rhodium coated plane mirror bent into a cylindrical form. The focusing properties of bent asymmetrically cut crystals have not yet been studied in depth. The present paper is devoted to study of a particular application of a bent asymmetrically cut crystal using ray tracing simulations with the SHADOW code. These simulations show that photon fluxes of order of 1.09x10{sup 11} photons/s will be available at the experimental focus at 8.79 keV. The focused beam dimensions will be 2.2 mm horizontal full width at half maximum (FWHM) by 0.12 mm vertical (FWHM).
Kravis, S. D.; Church, David A.; Johnson, B. M.; Meron, M.; Jones, K. W.; Levin, J. C.; Sellin, I. A.; Azuma, Y.; Berrahmansour, N.; Berry, H. G.; Druetta, M.
1992-01-01T23:59:59.000Z
-shell photoionization of Ar atoms, using broadband synchrotron x-ray radiation. K-electron removal resulted in vacancy cascading, yielding a distribution of argon-ion charge states peaked near Ar4+. The stored ion gas had an initial temperature near 480 K. The basic...
Kravis, S. D.; Church, David A.; Johnson, B. M.; Meron, M.; Jones, K. W.; Levin, J. C.; Sellin, I. A.; Azuma, Y.; Berrahmansour, N.; Berry, H. G.; Druetta, M.
1992-01-01T23:59:59.000Z
-shell photoionization of Ar atoms, using broadband synchrotron x-ray radiation. K-electron removal resulted in vacancy cascading, yielding a distribution of argon-ion charge states peaked near Ar4+. The stored ion gas had an initial temperature near 480 K. The basic...
Smith, R. M.; Liu, B.; Bai, J.; Wang, T., E-mail: t.wang@sheffield.ac.uk [Department of Electrical and Electronic Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)
2014-10-27T23:59:59.000Z
Hybrid organic/inorganic white light emitting structures have been fabricated based on a combination of high efficiency InGaN/GaN multiple quantum well (MQW) nanorod arrays and a yellow emitting co-polymer F8BT, leading to a minimised separation between them in order to achieve high efficiency non-radiative energy transfer (NRET). The NRET efficiency has been found 6.7 times higher at room temperature than at 7?K. This is attributed to the existence of strong exciton localization the InGaN MQWs, which can undergo thermally activated delocalization at high temperatures. The enhanced NRET efficiency is not only due to the delocalized MQW excitons, but also enhanced by the increased exciton diffusion at higher temperatures. This behaviour highlights the potential for high efficiency NRET in down-conversion hybrid white light emitting diodes operating at room temperature.
Pasciak, A [University of Tennessee Medical Center, Knoxville, TN (United States); Jones, A [MD Anderson Cancer Center, Houston, TX (United States); Wagner, L [UT Medical School, Houston, TX (United States)
2014-06-01T23:59:59.000Z
Purpose: Lightweight lead-free or lead-composite protective garments exploit k-edge interactions to attenuate scattered X-rays. Manufacturers specify the protective value of garments in terms of lead equivalence at a single kVp. This is inadequate, as the protection provided by such garments varies with radiation quality in different use conditions. We present a method for matching scattered X-ray spectra to primary X-ray spectra. The resulting primary spectra can be used to measure penetration through protective garments, and such measurements can be weighted and summed to determine a Diagnostic Radiation Index for Protection (DRIP). Methods: Scattered X-ray spectra from fluoroscopic procedures were modeled using Monte Carlo techniques in MCNP-X 2.7. Data on imaging geometry, operator position, patient size, and primary beam spectra were gathered from clinical fluoroscopy procedures. These data were used to generate scattered X-ray spectra resulting from procedural conditions. Technical factors, including kV and added filtration, that yielded primary X-ray spectra that optimally matched the generated scattered X-ray spectra were identified through numerical optimization using a sequential quadratic programming (SQP) algorithm. Results: The primary spectra generated with shape functions matched the relative flux in each bin of the scattered spectra within 5%, and half and quarter-value layers matched within 0.1%. The DRIP for protective garments can be determined by measuring the penetration through protective garments using the matched primary spectra, then calculating a weighted average according to the expected clinical use of the garment. The matched primary spectra are specified in terms of first and second half-value layers in aluminum and acrylic. Conclusion: Lead equivalence is inadequate for completely specifying the protective value of garments. Measuring penetration through a garment using full scatter conditions is very difficult. The primary spectra determined in this work allow for practical primary penetration measurements to be made with equipment readily available to clinical medical physicists.
Patel, Bhagubhai Desaibhai
1966-01-01T23:59:59.000Z
? FOR RADIATION NUMBER N + o 5 o MODULUS M = 4? USUAL PROCEDURE ~ S I NK' NTHI TA NODE I NO DE 2 NODE3 NODE4 NODE5 NODE6 0 ' oo0o n, 0100 0 ' 0200 n ~ c'300 0 ' 0400 0 ~ 0500 O, oeoo 0 ' 0700 Oe0800 0 ' 0900 Oe1000 n ~ 1100 Oe1200 Oo1300 0... of this method can be I'ound in the graphical method commonly known as the Schmidt method, but, Binder first developed it independently. During the peri, od in which these meth+de were developed the temperatures normally worked with were 'relatively lower...
Radiation Transport Calculations and Simulations
Fasso, Alberto; /SLAC; Ferrari, A.; /CERN
2011-06-30T23:59:59.000Z
This article is an introduction to the Monte Carlo method as used in particle transport. After a description at an elementary level of the mathematical basis of the method, the Boltzmann equation and its physical meaning are presented, followed by Monte Carlo integration and random sampling, and by a general description of the main aspects and components of a typical Monte Carlo particle transport code. In particular, the most common biasing techniques are described, as well as the concepts of estimator and detector. After a discussion of the different types of errors, the issue of Quality Assurance is briefly considered.
charlotb
2014-08-24T23:59:59.000Z
MA 16010 -- CALCULATOR POLICY. A ONE-LINE scientific calculator is REQUIRED. No other calculator is allowed. RECOMMENDED: TI-30Xa calculator
DRY TRANSFER FACILITY WORKER DOSE ASSESSMENT
J.S. Tang
2004-09-23T23:59:59.000Z
The purpose of this calculation is to estimate radiation doses received by personnel working in the Dry Transfer Facility No.1 (DTF-1) performing operations to receive transportation casks, transfer wastes, prepare waste packages, and ship out loaded waste packages and empty casks. Doses received by workers due to maintenance operations are also included in this revision. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation, excluding the remediation area of the building. The results of this calculation will be used to support the design of the DTF-1 and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in the Environmental and Nuclear Engineering.
Badnell's dielectronic calculations. Data for an ion is specified by the isoelectronic sequence.BADNELL.LIKE() where is the recombining isoelectronic sequence symbol is the specific recombining ion : name meaning SEQ sequence identifier (two characters) IZ0 nuclear charge ADFID ADAS data file type code
Rydberg, Bjorn; Cooper, Brian; Cooper, Priscilla K.; Holley, William; Chatterjee, Aloke
2004-01-01T23:59:59.000Z
S. Kim, and R. M. Myers. Radiation hybrid mapping: a somaticformulation of dual radiation action. Radiat. Res. 75: 471-High-Linear Energy Transfer Radiation in Human Fibroblasts.
Aller, M F; Aller, H D; Jorstad, S G; Marscher, A P; Bala, V; Hovatta, T
2015-01-01T23:59:59.000Z
As part of a program to identify the physical conditions in the jets of gamma-ray-flaring blazars detected by Fermi, including the role of shocks in the production of high-energy flaring, we obtained 4 years of 3-frequency, centimeter-band total flux density and linear polarization monitoring observations of the radio-bright blazar S5 0716+714 with the University of Michigan 26-m paraboloid. Light curves constructed from these data exhibit a series of rapid, high-amplitude, centimeter-band total flux density outbursts, and changes in the linear polarization consistent with the passage of shocks during the gamma-ray flaring. The observed spectral evolution of the radio-band flares, in combination with radiative transfer simulations incorporating propagating shocks, was used to constrain the shock and jet flow conditions in the parsec-scale regions of the jet. Eight forward-moving, transverse shocks with unusually-strong shock compression factors, a very fast Lorentz factor of the shocks of 77, a bulk Lorentz f...
charlotb
2014-06-10T23:59:59.000Z
MA 15800 – Calculators – GOOD AND BAD. ONLY ONE-LINE scientific calculators are permitted. *RECOMMENDED CALCULATOR: TI-30XA(See Below).
Calculation of heat flux through a wall containing a cavity: comparison of several models
Park, J.E.; Kirkpatrick, J.R.; Tunstall, J.N.; Childs, K.W.
1986-02-01T23:59:59.000Z
This paper describes the calculation of the heat transfer through the standard stud wall structure of a residential building. The wall cavity contains no insulation. Results from five test cases are presented. The first four represent progressively more complicated approximations to the heat transfer through and within a hollow wall structure. The fifth adds the model components necessary to severely inhibit the radiative energy transport across the empty cavity. Flow within the wall cavity is calculated from the Navier-Stokes equations and the energy conservation equation for an ideal gas using an improvement to the Implicit-Compressible Eulerian (ICE) algorithm of Harlow and Amsden. An algorithm is described to efficiently couple the fluid flow calculations to the radiation-conduction model for the solid portions of the system. Results indicate that conduction through still plates contributes less than 2% of the total heat transferred through a composite wall. All of the other elements (conduction through wall board, sheathing, and siding; convection from siding and wallboard to ambients; and radiation across the wall cavity) are required to accurately predict the heat transfer through a wall. Addition of a foil liner on one inner surface of the wall cavity reduces the total heat transferred by almost 50%.
Gustavsen, Arild
2009-01-01T23:59:59.000Z
free convection. In: Heat Transfer and Turbulent Buoyantof convection heat transfer and develop correlations.and radiation heat transfer and develop correlations for
Siewert, Charles E.
-grey heat transfer model is that of SIMMONS and FERZIGER(~)who used the normal modes(4) of the equation
Radiation Pressure in Massive Star Formation
Mark R. Krumholz; Richard I. Klein; Christopher F. McKee
2005-10-14T23:59:59.000Z
Stars with masses of >~ 20 solar masses have short Kelvin times that enable them to reach the main sequence while still accreting from their natal clouds. The resulting nuclear burning produces a huge luminosity and a correspondingly large radiation pressure force on dust grains in the accreting gas. This effect may limit the upper mass of stars that can form by accretion. Indeed, simulations and analytic calculations to date have been unable to resolve the mystery of how stars of 50 solar masses and up form. We present two new ideas to solve the radiation pressure problem. First, we use three-dimensional radiation hydrodynamic adaptive mesh refinement simulations to study the collapse of massive cores. We find that in three dimensions a configuration in which radiation holds up an infalling envelope is Rayleigh-Taylor unstable, leading radiation driven bubbles to collapse and accretion to continue. We also present Monte Carlo radiative transfer calculations showing that the cavities created by protostellar winds provides a valve that allow radiation to escape the accreting envelope, further reducing the ability of radiation pressure to inhibit accretion.
Feng, Qian
2011-10-21T23:59:59.000Z
A special challenge posed by mineral dust aerosols is associated with their predominantly nonspherical particle shapes. In the present study, the scattering and radiative properties for nonspherical mineral dust aerosols at violet-to-blue (0.412, 0...
Dr. Lazaros Oreopoulos and Dr. Peter M. Norris
2010-03-14T23:59:59.000Z
The overarching goal of the project was to improve the transfer of solar and thermal radiation in the most sophisticated computer tools that are currently available for climate studies, namely Global Climate Models (GCMs). This transfer can be conceptually separated into propagation of radiation under cloudy and under cloudless conditions. For cloudless conditions, the factors that affect radiation propagation are gaseous absorption and scattering, aerosol particle absorption and scattering and surface albedo and emissivity. For cloudy atmospheres the factors are the various cloud properties such as cloud fraction, amount of cloud condensate, the size of the cloud particles, and morphological cloud features such as cloud vertical location, cloud horizontal and vertical inhomogeneity and cloud shape and size. The project addressed various aspects of the influence of the above contributors to atmospheric radiative transfer variability. In particular, it examined: (a) the quality of radiative transfer for cloudless and non-complex cloudy conditions for a substantial number of radiation algorithms used in current GCMs; (b) the errors in radiative fluxes from neglecting the horizontal variabiity of cloud extinction; (c) the statistical properties of cloud horizontal and vertical cloud inhomogeneity that can be incorporated into radiative transfer codes; (d) the potential albedo effects of changes in the particle size of liquid clouds; (e) the gaseous radiative forcing in the presence of clouds; and (f) the relative contribution of clouds of different sizes to the reflectance of a cloud field. To conduct the research in the various facets of the project, data from both the DOE ARM project and other sources were used. The outcomes of the project will have tangible effects on how the calculation of radiative energy will be approached in future editions of GCMs. With better calculations of radiative energy in GCMs more reliable predictions of future climate states will be attainable, thus affecting public policy decisions with great impact to public life.
charlotb
2014-08-15T23:59:59.000Z
MA 15300 Calculator Policy. ONLY a TI-30Xa scientific calculator is allowed on quizzes and exams. If you have questions, please email the course coordinator ...
charlotb
2014-12-17T23:59:59.000Z
MA 15910 Calculator Policy. ONLY a TI-30Xa scientific calculator is allowed on quizzes and exams. If you have questions, please email the course coordinator ...
Power transfer through strongly coupled resonances
Kurs, André
2007-01-01T23:59:59.000Z
Using self-resonant coils in a strongly coupled regime, we experimentally demonstrate efficient non-radiative power transfer over distances of up to eight times the radius of the coils. We use this system to transfer 60W ...
Heat transfer pathways in underfloor air distribution (UFAD) systems
Bauman, F.; Jin, H.; Webster, T.
2006-01-01T23:59:59.000Z
is little radiative heat transfer and little impact on thereturn air extrac- tion and heat transfer to the plenum. ItUFAD is often used and heat transfer out of the room through
, Australian National University, Canberra, ACT 0200, Australia 4 School of Mech. and Manufact. Engineering, University of New South Wales, Sydney 2052, Australia ABSTRACT Transient radiative transfer effects power is sufficiently accurate at duration of laser pulse more than about 10 ps. The calculations
Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference
Guo, Zhixiong "James"
-dependent radiation and conduction bio-heat transfer model. Ultrashort pulsed radiation transport in the cylindrical a combined transient heat transfer and Pennes bio-heat transfer model is developed to simulate the heat transfer models; and concluded that the Pennes model is still the most practical for fast prediction
Zhai, Pengwang
2009-06-02T23:59:59.000Z
meter. 60 20 Geometry of a scattering event. . . . . . . . . . . . . . . . . . . . . . 63 21 An example of the atmosphere model used in the 3D Monte Carlo code for the vector radiative transfer systems. Inhomogeneous layers are divided into voxels... cases can be solved analytically. Several popular numerical methods include the T-matrix method [15, 16, 17, 18, 19], finite-element method [20, 21], finite-difference time-domain(FDTD)method[22,23,24,25,26,27,28,29,30,31,32], point-matching method [33...
Molecular Dynamics Investigation of Ferrous-Ferric Electron Transfer...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Electron Transfer in a Hydrolyzing Aqueous Solution: Calculation of the pH Molecular Dynamics Investigation of Ferrous-Ferric Electron Transfer in a Hydrolyzing Aqueous Solution:...
Near-field heat transfer between gold nanoparticle arrays
Phan, Anh D., E-mail: anhphan@mail.usf.edu [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States); Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Ba Dinh, Hanoi 10000 (Viet Nam); Phan, The-Long, E-mail: ptlong2512@yahoo.com [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Woods, Lilia M. [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States)
2013-12-07T23:59:59.000Z
The radiative heat transfer between gold nanoparticle layers is presented using the coupled dipole method. Gold nanoparticles are modelled as effective electric and magnetic dipoles interacting via electromagnetic fluctuations. The effect of higher-order multipoles is implemented in the expression of electric polarizability to calculate the interactions at short distances. Our findings show that the near-field radiation reduces as the radius of the nanoparticles is increased. Also, the magnetic dipole contribution to the heat exchange becomes more important for larger particles. When one layer is displayed in parallel with respect to the other layer, the near-field heat transfer exhibits oscillatory-like features due to the influence of the individual nanostructures. Further details about the effect of the nanoparticles size are also discussed.
Diaz, F.; Vilkas, M. J.; Ishikawa, Y. [Department of Chemistry and the Chemical Physics Program, University of Puerto Rico, P.O. Box 23346, San Juan, PR 00931-3346 (Puerto Rico); Beiersdorfer, P., E-mail: beiersdorfer1@llnl.gov [Physics Division, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)
2013-07-01T23:59:59.000Z
Accurate theoretical energy level, lifetime, and transition probability calculations of core-excited Fe XVI were performed employing the relativistic Multireference Moller-Plesset perturbation theory. In these computations the term energies of the highly excited n {<=} 5 states arising from the configuration 1s {sup 2}2s{sup k} 2p{sup m} 3l {sup p} nl' {sup q}, where k + m + p + q = 9, l {<=} 3 and p + q {<=} 2 are considered, including those of the autoionizing levels with a hole-state in the L-shell. All even and odd parity states of sodium-like iron ion were included for a total of 1784 levels. Comparison of the calculated L-shell transition wavelengths with those from laboratory measurements shows excellent agreement. Therefore, our calculation may be used to predict the wavelengths of as of yet unobserved Fe XVI, such as the second strongest 2p-3d Fe XVI line, which has not been directly observed in the laboratory and which blends with one of the prominent Fe XVII lines.
Chardin, Jonathan; Aubert, Dominique; Puchwein, Ewald
2015-01-01T23:59:59.000Z
We calibrate here cosmological radiative transfer simulation with ATON/RAMSES with a range of measurements of the Lyman alpha opacity from QSO absorption spectra. We find the Lyman alpha opacity to be very sensitive to the exact timing of hydrogen reionisation. Models reproducing the measured evolution of the mean photoionisation rate and average mean free path reach overlap at z ~ 7 and predict an accelerated evolution of the Lyman alpha opacity at z > 6 consistent with the rapidly evolving luminosity function of Lyman alpha emitters in this redshift range. Similar to "optically thin" simulations our full radiative transfer simulations fail, however, to reproduce the high-opacity tail of the Lyman alpha opacity PDF at z > 5. We argue that this is due to spatial UV fluctuations in the post-overlap phase of reionisation on substantially larger scales than predicted by our source model, where the ionising emissivity is dominated by large numbers of sub-L* galaxies. We further argue that this suggests a signific...
Jones, T.D.; Morris, M.D.; Wells, S.M.; Young, R.W.
1986-12-01T23:59:59.000Z
Studies conducted during the 1950s and 1960s of radiation-induced mortality to diverse animal species under various exposure protocols were compiled into a mortality data base. Some 24 variables were extracted and recomputed from each of the published studies, which were collected from a variety of available sources, primarily journal articles. Two features of this compilation effort are (1) an attempt to give an estimate of the uniform dose received by the bone marrow in each treatment so that interspecies differences due to body size were minimized and (2) a recomputation of the LD/sub 50/ where sufficient experimental data are available. Exposure rates varied in magnitude from about 10/sup -2/ to 10/sup 3/ R/min. This report describes the data base, the sources of data, and the data-handling techniques; presents a bibliography of studies compiled; and tabulates data from each study. 103 refs., 44 tabs.
Roesler, J.; Groettrup, E.B.; Baccarini, M.; Lohmann-Mattes, M.L. (Fraunhofer-Institut ITA, Hannover (Germany, F.R.))
1989-09-01T23:59:59.000Z
Radiation chimeras in the early phase after bone marrow transplantation are a good model to study the efficiency of the body's nonspecific defense system represented by macrophages (M phi), polymorphonuclear cells (PMN), and NK cells. These cell types are present in large numbers in spleen and liver at that time, whereas the specific immune system represented by T and B cells is functionally deficient. We previously reported enhanced activities in vitro of M phi (and PMN) from recipient animals in an early phase after allogeneic bone marrow transfer. We here demonstrate that these activities result in enhanced spontaneous resistance against Listeria monocytogenes in vivo: CFU of L. monocytogenes in spleen and liver 48 h after infection were about 1 or 2 to 4 log steps less than in untreated control mice of donor or host haplotype. This enhanced resistance decreased over the 4-mo period after marrow transfer. Preactivated M phi were identified as the most important effector cells. Isolated from spleen and peritoneal cavity, they performed enhanced killing of phagocytosed Listeria. Such preactivated M phi occurred in recipient animals after transfer of allogeneic but not of syngeneic bone marrow. The precise mechanism of M phi activation in the allogeneic radiation chimera in the complete absence of any detectable T cell function is not clear at present. However, these preactivated M phi display an important protective effect against L. monocytogenes: chimeras could eliminate Listeria without acquisition of positive delayed-type sensitivity when infected with 10(3) bacteria. An inoculum of 5 . 10(3) L. monocytogenes resulted either in prolonged survival compared with normal mice of the recipient haplotype or in definitive survival accompanied by a positive delayed-type sensitivity.
Ivanov, Michael A Liberman M F
2015-01-01T23:59:59.000Z
We examines regimes of the hydrogen flames propagation and ignition of mixtures heated by the radiation emitted from the flame. The gaseous phase is assumed to be transparent for radiation, while the suspended particles of the dust cloud ahead of the flame absorb and reemit the radiation. The radiant heat absorbed by the particles is then lost by conduction to the surrounding unreacted gaseous phase so that the gas phase temperature lags that of the particles. The direct numerical simulations solve the full system of two phase gas dynamic time-dependent equations with a detailed chemical kinetics for a plane flames propagating through a dust cloud. Depending on the spatial distribution of the dispersed particles and on the value of radiation absorption length the consequence of the radiative preheating of the unreacted mixture can be either the increase of the flame velocity for uniformly dispersed particles or ignition deflagration or detonation ahead of the flame via the Zel'dovich gradient mechanism in the...
Enhanced heat transfer for thermionic power modules
Johnson, D.C.
1981-07-01T23:59:59.000Z
The thermionic power module is capable of operating at very high heat fluxes, which in turn serve to reduce capital costs. The most efficient operation also requires uniform heat fluxes. The development of enhanced heat transfer systems is required to meet the demand for high heat fluxes (>20 w/cm/sup 2/) at high temperatures (>1500K) which advanced thermionic power modules place upon combustion systems. Energy transfer from the hot combustion gases may take place by convection, radiation, or a combination of radiation and convection. Enhanced convective heat transfer with a jet impingement system has been demonstrated in a thermionic converter. The recently-developed cellular ceramic radiative heat transfer system has also been applied to a thermionic converter. By comparing the jet impingement and cellular ceramic radiative heat transfer systems, an appropriate system may be selected for utilization in advanced thermionic power modules. Results are reported.
Energy Transfer between Throats from a 10d Perspective
B. v. Harling; A. Hebecker; T. Noguchi
2008-03-28T23:59:59.000Z
Strongly warped regions, also known as throats, are a common feature of the type IIB string theory landscape. If one of the throats is heated during cosmological evolution, the energy is subsequently transferred to other throats or to massless fields in the unwarped bulk of the Calabi-Yau orientifold. This energy transfer proceeds either by Hawking radiation from the black hole horizon in the heated throat or, at later times, by the decay of throat-localized Kaluza-Klein states. In both cases, we calculate in a 10d setup the energy transfer rate (respectively decay rate) as a function of the AdS scales of the throats and of their relative distance. Compared to existing results based on 5d models, we find a significant suppression of the energy transfer rates if the size of the embedding Calabi-Yau orientifold is much larger than the AdS radii of the throats. This effect can be partially compensated by a small distance between the throats. These results are relevant, e.g., for the analysis of reheating after brane inflation. Our calculation employs the dual gauge theory picture in which each throat is described by a strongly coupled 4d gauge theory, the degrees of freedom of which are localized at a certain position in the compact space.
ME 339 Heat Transfer ABET EC2000 syllabus
Ben-Yakar, Adela
ME 339 Heat Transfer Page 1 ABET EC2000 syllabus ME 339 Heat Transfer Spring 2010 Required convection; radiation; introduction to phase change heat transfer and to heat exchangers. Prerequisite(s): ME, Fundamentals of Heat and Mass Transfer, 6th ed., Wiley Other Required Material: NA Course Objectives
Ganapathy, V.
1982-01-01T23:59:59.000Z
Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)
Development of a Heat Transfer Model for the Integrated Facade Heating
Gong, X.; Archer, D. H.; Claridge, D. E.
2007-01-01T23:59:59.000Z
the heat transfer process of facade heating (mullion radiators) in a pilot research project in Pittsburgh, PA. The heat transfer model for facade heating is developed and verified by measured data. The comparison shows that the heat transfer model predicts...
Development of a Heat Transfer Model for the Integrated Facade Heating
Gong, X.; Archer, D. H.; Claridge, D. E.
2007-01-01T23:59:59.000Z
the heat transfer process of facade heating (mullion radiators) in a pilot research project in Pittsburgh, PA. The heat transfer model for facade heating is developed and verified by measured data. The comparison shows that the heat transfer model predicts...
Radiation Sources and Radioactive Materials (Connecticut)
Broader source: Energy.gov [DOE]
These regulations apply to persons who receive, transfer, possess, manufacture, use, store, handle, transport or dispose of radioactive materials and/or sources of ionizing radiation. Some...
Âdifferential equations that model steadyÂstate combined conductiveÂradiative heat transfer. This system of equationsÂBrakhage algorithm. Key words. conductiveÂradiative heat transfer, multilevel algorithm, compact fixed point problems integroÂdifferential equations that model steadyÂstate combined conductiveÂradiative heat transfer
None
2011-12-05T23:59:59.000Z
HEATS Project: USF is developing low-cost, high-temperature phase-change materials (PCMs) for use in thermal energy storage systems. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. Most PCMs do not conduct heat very well. Using an innovative, electroless encapsulation technique, USF is enhancing the heat transfer capability of its PCMs. The inner walls of the capsules will be lined with a corrosion-resistant, high-infrared emissivity coating, and the absorptivity of the PCM will be controlled with the addition of nano-sized particles. USF’s PCMs remain stable at temperatures from 600 to 1,000°C and can be used for solar thermal power storage, nuclear thermal power storage, and other applications.
asme heat transfer: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
fundamental laws of heat transfer (conduction, convection and radiation) and give useful data specific to cryogenic conditions (thermal contact resistance, total emissivity of...
Surface Radiation from GOES: A Physical Approach; Preprint
Habte, A.; Sengupta, M.; Wilcox, S.
2012-09-01T23:59:59.000Z
Models to compute Global Horizontal Irradiance (GHI) and Direct Normal Irradiance (DNI) have been in development over the last 3 decades. These models can be classified as empirical or physical, based on the approach. Empirical models relate ground based observations with satellite measurements and use these relations to compute surface radiation. Physical models consider the radiation received from the earth at the satellite and create retrievals to estimate surface radiation. While empirical methods have been traditionally used for computing surface radiation for the solar energy industry the advent of faster computing has made operational physical models viable. The Global Solar Insolation Project (GSIP) is an operational physical model from NOAA that computes GHI using the visible and infrared channel measurements from the GOES satellites. GSIP uses a two-stage scheme that first retrieves cloud properties and uses those properties in a radiative transfer model to calculate surface radiation. NREL, University of Wisconsin and NOAA have recently collaborated to adapt GSIP to create a 4 km GHI and DNI product every 30 minutes. This paper presents an outline of the methodology and a comprehensive validation using high quality ground based solar data from the National Oceanic and Atmospheric Administration (NOAA) Surface Radiation (SURFRAD) (http://www.srrb.noaa.gov/surfrad/sitepage.html) and Integrated Surface Insolation Study (ISIS) http://www.srrb.noaa.gov/isis/isissites.html), the Solar Radiation Research Laboratory (SRRL) at National Renewable Energy Laboratory (NREL), and Sun Spot One (SS1) stations.
MEASUREMENT AND ANALYSIS OF CIRCUMSOLAR RADIATION
Grether, Donald
2013-01-01T23:59:59.000Z
cloud transient studies); Sandia, Albuquerque (input to performance calculation program Helios); SERI (analysis of effect of circumsolar radiation
Aller, M F; Aller, H D; Latimer, G E; Hovatta, T
2014-01-01T23:59:59.000Z
To investigate parsec-scale jet flow conditions during GeV gamma-ray flares detected by the Fermi Large Angle Telescope, we obtained centimeter-band total flux density and linear polarization monitoring observations from 2009.5 through 2012.5 with the 26-meter Michigan radio telescope for a sample of core-dominated blazars. We use these data to constrain radiative transfer simulations incorporating propagating shocks oriented at an arbitrary angle to the flow direction in order to set limits on the jet flow and shock parameters during flares temporally associated with gamma-ray flares in 0420-014, OJ 287, and 1156+295; these AGN exhibited the expected signature of shocks in the linear polarization data. Both the number of shocks comprising an individual radio outburst (3-4) and the range of the compression ratios of the individual shocks (0.5-0.8) are similar in all three sources; the shocks are found to be forward-moving with respect to the flow. While simulations incorporating transverse shocks provide good...
CORQUENCH: A model for gas sparging-enhanced, melt-water, film-boiling heat transfer
Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.
1990-01-01T23:59:59.000Z
In evaluation of severe-accident sequences for water-cooled nuclear reactors, molten core materials may be postulated to be released into the containment and accumulate on concrete. The heatup and decomposition of concrete is accompanied by the release of water vapor and carbon dioxide gases. Gases flowing through the melt upper surface can influence the rates of heat transfer to water overlying the melt. In particular, the gas flow through the interface can be envisioned to enhance the heat removal from the melt. A mechanistic model (CORQUENCH) has been developed to describe film-boiling heat transfer between a molten pool and an overlying coolant layer in the presence of sparging gas. The model favorably predicts the lead-Feron 11 data of Greene and Greene et al. for which the calculations indicate that area enhancement in the conduction heat transfer across the film is the predominant mechanism leading to augmentation in the heat flux as the gas velocity increases. Predictions for oxidic corium indicate a rapid increase in film-boiling heat flux as the gas velocity rises. The predominant mode of heat transfer for this case is radiation, and the increase in heat flux with gas velocity is primarily a result of interfacial area enhancement of the radiation component of the overall heat transfer coefficient. The CORQUENCH model has been incorporated into the MELTSPREAD-1 computer code{sup 6} for the analysis of transient spreading in containments.
Bournel, F.; Carniato, S.; Dufour, G.; Gallet, J.-J.; Ilakovac, V.; Rangan, S.; Rochet, F.; Sirotti, F. [Laboratoire de Chimie Physique Matiere et Rayonnement, Universite Pierre et Marie Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05 (France); Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, Boite Postale 48, 91192 Gif sur Yvette Cedex (France)
2006-03-15T23:59:59.000Z
The room temperature adsorption of acetonitrile (CH{sub 3}-C{identical_to}N) on Si(111)-7x7 is examined by synchrotron radiation N 1s x-ray photoemission and x-ray absorption spectroscopies. The experimental spectroscopic data point to multiple adsorption geometries. Candidate structures are optimized using density functional theory (DFT), the surface being simulated by silicon clusters encompassing one (adjacent) adatom-rest atom pair. This is followed by the DFT calculation of electron transition energies and cross sections. The comparison of theoretical spectra with experimental ones indicates that the molecule is adsorbed on the surface under two forms, a nondissociated geometry (an sp{sup 2}-hybridized CN) and a dissociated one (leading to a pendent sp-hybridized CN). In the nondissociative mode, the molecule bridges an adatom-rest atom pair. For bridge-type models, the discussion of the core-excited state calculations is focussed on the so-called silicon-molecule mixed-state transitions that strongly depend on the breaking or not of the adatom backbonds and on the attachment of the nitrogen end either to the adatom or to the rest atom. Concerning the dissociated state, the CH bond cleavage leads to a cyanomethyl (Si-CH{sub 2}-CN) plus a silicon monohydride, which accounts for the spectroscopic evidence of a free C{identical_to}N group (we do not find at 300 K any spectroscopic evidence for a C{identical_to}N group datively bonded to a silicon atom via its nitrogen lone pair). Therefore the reaction products of acetonitrile on Si(111)-7x7 are similar to those detected on the Si(001)-2x1 surface at the same temperature, despite the marked differences in the reconstruction of those two surfaces, especially the distance between adjacent silicon broken bonds. In that respect, we discuss how adatom backbond breaking in the course of adsorption may explain why both surface orientations react the same way with acetonitrile.
Plutonium 239 Equivalency Calculations
Wen, J
2011-05-31T23:59:59.000Z
This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.
Available transfer capability and first order sensitivity
Gravener, M.H. [PJM Interconnection, L.L.C., Valley Forge, PA (United States)] [PJM Interconnection, L.L.C., Valley Forge, PA (United States); Nwankpa, C. [Drexel Univ., Philadelphia, PA (United States)] [Drexel Univ., Philadelphia, PA (United States)
1999-05-01T23:59:59.000Z
A method of calculating Available Transfer Capability and the exploration of the first order effects of certain power system network variables are described. The Federal Energy Regulatory Commission has ordered that bulk electrical control areas must provide to market participants a ``commercially viable`` network transfer capability for the import, export, and through-put of energy. A practical method for deriving this transfer capability utilizing both linear and non-linear power flow analysis methods is developed that acknowledges both thermal and voltage system limitations. The Available Transfer Capability is the incremental transfer capability derived by the method reduced by margins. A procedure for quantifying the first order effect of network uncertainties such as load forecast error and simultaneous transfers on the calculated transfer capability of a power system snapshot are explored. The quantification of these network uncertainties can provide information necessary for system operation, planning, and energy market participation.
OwenDavis
2014-08-22T23:59:59.000Z
MA 22400 -- CALCULATOR POLICY. A ONE-LINE scientific calculator is REQUIRED. No other calculator is allowed. RECOMMENDED: TI-30Xa calculator
Medical physics calculations with MCNP: a primer
Lazarine, Alexis D
2006-10-30T23:59:59.000Z
of Medical Internal Radiation Dose (MIRD) specific absorbed fraction (SAF) values using the ORNL MIRD phantom, x-ray phototherapy effectiveness, prostate brachytherapy lifetime dose calculations, and a radiograph of the head using the Zubal head phantom. Also...
Medical physics calculations with MCNP: a primer
Lazarine, Alexis D
2006-10-30T23:59:59.000Z
of Medical Internal Radiation Dose (MIRD) specific absorbed fraction (SAF) values using the ORNL MIRD phantom, x-ray phototherapy effectiveness, prostate brachytherapy lifetime dose calculations, and a radiograph of the head using the Zubal head phantom. Also...
Simulation of adsorption of uranium from seawater using liquid film mass transfer controlling model
Omichi, H.; Kataki, A.; Okamoto, J.
1988-08-01T23:59:59.000Z
A liquid film mass transfer control model was applied to the batch adsorption of uranium from seawater with an amidoxime-group-containing polymeric adsorbent made by the radiation-induced grafting method. The adsorption amount was calculated by changing two parameters, equilibrium adsorption amount q/sub 0/ and liquid film mass transfer coefficient k, to obtain the best fit between the observed and calculate values. The index of a Freundlich-type isotherm was obtained as 1.6, which is similar to the previously observed value with hydrous titanium oxide adsorbent. The plot k vs 1/T provided the activation energy as 10.0 kcal/mol. Both q/sub 0/ and k showed an approximately first-order dependency on the amidoxime group content in the adsorbent. The simulation made it clear that the increase in k brought about by mixing amidoxime groups with carboxyl groups was due to a synergistic effect of these groups.
Cherenkov Radiation from e+e- Pairs and Its Effect on nu e Induced Showers
Mandal, Sourav K.; Klein, Spencer R.; Jackson, J. David
2005-01-01T23:59:59.000Z
5] J. V. Jelley, Cherenkov Radiation and its applications (calculated the Cherenkov radiation from e + e ? pairs as a? 2 [1?? 2 ?(?)]), the radiation is suppressed compared to
Measurements and modeling of soot formation and radiation in microgravity jet diffusion flames
Ku, J.C.; Tong, L. [Wayne State Univ., Detroit, MI (United States). Mechanical Engineering Dept.; Greenberg, P.S. [NASA Lewis Research Center, Cleveland, OH (United States). Microgravity Combustion Branch
1996-12-31T23:59:59.000Z
This is a computational and experimental study for soot formation and radiative heat transfer in jet diffusion flames under normal gravity (1-g) and microgravity (0-g) conditions. Instantaneous soot volume fraction maps are measured using a full-field imaging absorption technique developed by the authors. On modeling, the authors have coupled flame structure and soot formation models with detailed radiation transfer calculations. Favre-averaged boundary layer equations with a k-e-g turbulence model are used to predict the flow field, and a conserved scalar approach with an assumed {beta}-pdf are used to predict gaseous species mole fraction. Scalar transport equations are used to describe soot volume fraction and number density distributions, with formation and oxidation terms modeled by one-step rate equations and thermophoretic effects included. An energy equation is included to couple flame structure and radiation analyses through iterations, neglecting turbulence-radiation interactions. The YIX solution for a finite cylindrical enclosure is used for radiative heat transfer calculations. The spectral absorption coefficient for soot aggregates is calculated from the Rayleigh solution using complex refractive index data from a Drude-Lorentz model. The exponential-wide-band model is used to calculate the spectral absorption coefficient for H{sub 2}O and CO{sub 2}. Predicted soot volume fraction and temperature results agree well with published data for a normal gravity co-flow laminar flames and turbulent jet flames. Predicted soot volume fraction results also agree with the data for 1-g and 0-g laminar jet flames as well as 1-g turbulent jet flames.
attenuates gamma radiation: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Galactic interstellar radiation field, we calculate the attenuation of the very high energy gamma rays from the Galactic sources. The infra-red radiation background near the...
abscopal radiation effects: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of symmetry. Numerical calculations in three dimensions of the radiative energy density, flux and pressure created by a stationary shock wave show how the radiation decreases...
NNSA Transfers Responsibility for Radiation Detection System...
National Nuclear Security Administration (NNSA)
installation at the Port of Yangshan was completed in November 2011. Over a three year transition period, SLD and GACC worked toward enhancing GACC's capabilities and expertise...
Journal of Quantitative Spectroscopy & Radiative Transfer ] (
Gamache, Robert R.
with the new set of molecular data is evaluated directly from vertical H2O concentration profiles. r 2004 Elsevier Ltd. All rights reserved. Keywords: Diode laser; Near-infrared spectrometer; Ab initio and carbon dioxide in the lower stratosphere [1]. Both sensors have been involved in several European
Posters Comparison of Stochastic Radiation Transfer Predictions
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations719 Posters
Posters The Effects of Radiative Transfer
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations7197117313
Bridging conduction and radiation : investigating thermal transport in nanoscale gaps
Chiloyan, Vazrik
2015-01-01T23:59:59.000Z
Near field radiation transfer between objects separated by small gaps is a widely studied field in heat transfer and has become more important than ever. Many technologies such as heat assisted magnetic recording, aerogels, ...
Radiation: Radiation Control (Indiana)
Broader source: Energy.gov [DOE]
It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...
Dt2boool2> Nora Heat Transfer Correlations
Dt2boool2> Nora Heat Transfer Correlations in Nuclear Reactor Safety Calculations VW ÉAiiattÉaii #12;fcflison cufiMiMltt lor yhdyiifci aomicantfgy RIS0-M-25O4 6«.*). HEAT TRANSFER of work 26 3. PRESENT KNOWLEDGE 27 3.1. General considerations 27 3.2. Heat transfer in different flow
Paller, Michael H.; Jannika, G. Timothy; Wike, Lynn D
2005-10-04T23:59:59.000Z
{sup 137}Cs transfer factors were computed for small mammals collected from the dried sediment areas of a partially drained, contaminated reservoir. Soil {sup 137}Cs concentrations were heterogeneous on small and large spatial scales, with a geometric mean of 253.1 Bq/kg dry weight. About 50% of the variance in cotton rat Sigmodon hispidus tissue {sup 137}Cs levels was explained by variation in soil {sup 137}Cs levels. Soil to animal transfer factors (whole body dry weight) averaged 6.0 for cotton rats and 1.2 for cotton mice Peromyscus gossypinus. These values are similar to {sup 137}Cs transfer factors for herbivorous, homeothermic animals from other contaminated ecosystems. Site-specific transfer factors can significantly affect the estimation of dose. In the RESRAD-BIOTA dose model, the default transfer factor for {sup 137}Cs in terrestrial animals is 110 resulting in an estimate of radiation dose to terrestrial biota that is 16 times more than the dose calculated with the actual measured transfer factor.
Multigroup radiation hydrodynamics with flux-limited diffusion and adaptive mesh refinement
González, Matthias; Commerçon, Benoît; Masson, Jacques
2015-01-01T23:59:59.000Z
Radiative transfer plays a key role in the star formation process. Due to a high computational cost, radiation-hydrodynamics simulations performed up to now have mainly been carried out in the grey approximation. In recent years, multi-frequency radiation-hydrodynamics models have started to emerge, in an attempt to better account for the large variations of opacities as a function of frequency. We wish to develop an efficient multigroup algorithm for the adaptive mesh refinement code RAMSES which is suited to heavy proto-stellar collapse calculations. Due to prohibitive timestep constraints of an explicit radiative transfer method, we constructed a time-implicit solver based on a stabilised bi-conjugate gradient algorithm, and implemented it in RAMSES under the flux-limited diffusion approximation. We present a series of tests which demonstrate the high performance of our scheme in dealing with frequency-dependent radiation-hydrodynamic flows. We also present a preliminary simulation of a three-dimensional p...
Broader source: Energy.gov [DOE]
Original Impact Calculations, from the Tool Kit Framework: Small Town University Energy Program (STEP).
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Data Transferring Data Advice and Overview NERSC provides many facilities for storing data and performing analysis. However, transfering data - whether over the wide area network...
Conference on Atmospheric Radiation, 6th, Williamsburg, VA, May 13-16, 1986, Extended Abstracts
Not Available
1986-01-01T23:59:59.000Z
Numerous topics of interest for measurements and modeling of radiation in the atmosphere are discussed, with emphasis on satellite remote sensing capabilities, data analysis techniques and climatological impact. Attention is devoted to aerosols at all levels of the atmosphere, the current understanding of potential nuclear winter scenarios, and to instruments which are used for sensing radiance in the atmosphere. Consideration is also given to spectroscopy and band models, radiative transfer calculations, earth radiation budget (ERB) models and their interaction with GCMs, and to climate models. In-depth analyses are performed of data from the ERB instruments on the Nimbus-7 spacecraft and to validation procedures being developed for data collected by the ERB satellite.
Cooling load calculations for radiant systems: are they the same traditional methods?
Bauman, Fred; Feng, Jingjuan Dove; Schiavon, Stefano
2013-01-01T23:59:59.000Z
heat transfer is handled in traditional cooling load calculationheat gain is well recognized by cooling load calculationload calculations for radiant systems should use the ASHRAE heat
Daylighting Calculation in DOE-2
Winkelmann, F.C
2013-01-01T23:59:59.000Z
46 3.2.2 Luminous Efficacy of Solar Radiation . . . . . . .The Availability of Solar Radiation. and Daylight",incidence TSOLNM for solar radiation. TSOLDF =
Radiation physics, biophysics, and radiation biology
Hall, E.J.
1992-05-01T23:59:59.000Z
The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.
Photo-Thermal Transfer Function of Dielectric Mirrors for Precision Measurements
Stefan W. Ballmer
2015-01-07T23:59:59.000Z
The photo-thermal transfer function from absorbed power incident on a dielectric mirror to the effective mirror position is calculated using the coating design as input. The effect is found to change in amplitude and sign for frequencies corresponding to diffusion length comparable to the coating thickness. Transfer functions are calculated for the $Ti$-doped ${\\rm Ta_2O_5:SiO_2}$ coating used in Advanced LIGO and for a crystalline ${\\rm Al_xGa_{1-x}As}$ coating. The shape of the transfer function at high frequencies is shown to be a sensitive indicator of the effective absorption depth, providing a potentially powerful tool to distinguish coating-internal absorption from surface contamination related absorption. The sign change of the photo-thermal effect could also be useful to stabilize radiation pressure-based opto-mechanical systems. High frequency corrections to the previously published thermo-optic noise estimates are also provided. Finally, estimating the quality of the thermo-optic noise cancellation occurring in fine-tuned ${\\rm Al_xGa_{1-x}As}$ coatings requires the detailed heat flow analysis done in this paper.
Cooperative heat transfer and ground coupled storage system
Metz, Philip D. (Rocky Point, NY)
1982-01-01T23:59:59.000Z
A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.
Radiation from Accelerated Branes
Mohab Abou-Zeid; Miguel S. Costa
2000-01-29T23:59:59.000Z
The radiation emitted by accelerated fundamental strings and D-branes is studied within the linear approximation to the supergravity limit of string theory. We show that scalar, gauge field and gravitational radiation is generically emitted by such branes. In the case where an external scalar field accelerates the branes, we derive a Larmor-type formula for the emitted scalar radiation and study the angular distribution of the outgoing energy flux. The classical radii of the branes are calculated by means of the corresponding Thompson scattering cross sections. Within the linear approximation, the interaction of the external scalar field with the velocity fields of the branes gives a contribution to the observed gauge field and gravitational radiation.
Passive-solar directional-radiating cooling system
Hull, J.R.; Schertz, W.W.
1985-06-27T23:59:59.000Z
A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.
Passive-solar directional-radiating cooling system
Hull, John R. (Hinsdale, IL); Schertz, William W. (Batavia, IL)
1986-01-01T23:59:59.000Z
A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.
Calculation of external dose from distributed source
Kocher, D.C.
1986-01-01T23:59:59.000Z
This paper discusses a relatively simple calculational method, called the point kernel method (Fo68), for estimating external dose from distributed sources that emit photon or electron radiations. The principles of the point kernel method are emphasized, rather than the presentation of extensive sets of calculations or tables of numerical results. A few calculations are presented for simple source geometries as illustrations of the method, and references and descriptions are provided for other caluclations in the literature. This paper also describes exposure situations for which the point kernel method is not appropriate and other, more complex, methods must be used, but these methods are not discussed in any detail.
Gluon Radiation in Top Production and Decay
Cosmin Macesanu; Lynne H. Orr
2000-01-14T23:59:59.000Z
We present the results of an exact calculation of gluon radiation in top production and decay at high energy electron-positron colliders. We include all spin correlations and interferences, the bottom quark mass, and finite top width effects in the matrix element calculation. We study properties of the radiated gluons and implications for top mass measurement.
RADIATIVE COOLING IMPLEMENTATIONS IN SIMULATIONS OF PRIMORDIAL STAR FORMATION
Hirano, Shingo [Department of Astronomy, School of Science, University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan)] [Department of Astronomy, School of Science, University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan); Yoshida, Naoki, E-mail: hirano@astron.s.u-tokyo.ac.jp, E-mail: naoki.yoshida@ipmu.jp [Department of Physics, School of Science, University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan)] [Department of Physics, School of Science, University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan)
2013-01-20T23:59:59.000Z
We study the thermal evolution of primordial star-forming gas clouds using three-dimensional cosmological simulations. We critically examine how assumptions and approximations made in calculating radiative cooling rates affect the dynamics of the collapsing gas clouds. We consider two important molecular hydrogen cooling processes that operate in a dense primordial gas: H{sub 2} line cooling and continuum cooling by H{sub 2} collision-induced emission. To calculate the optically thick cooling rates, we follow the Sobolev method for the former, whereas we perform ray tracing for the latter. We also run the same set of simulations using simplified fitting functions for the net cooling rates. We compare the simulation results in detail. We show that the time- and direction-dependence of hydrodynamic quantities such as gas temperature and local velocity gradients significantly affects the optically thick cooling rates. Gravitational collapse of the cloud core is accelerated when the cooling rates are calculated by using the fitting functions. The structure and evolution of the central pre-stellar disk are also affected. We conclude that physically motivated implementations of radiative transfer are necessary to follow accurately the thermal and chemical evolution of a primordial gas to high densities.
de Boer, Gijs; Collins, William D.; Menon, Surabi; Long, Charles N.
2011-12-02T23:59:59.000Z
Measurements from ground-based cloud radar, high spectral resolution lidar and microwave radiometer are used in conjunction with a column version of the Rapid Radiative Transfer Model (RRTMG) and radiosonde measurements to derive the surface radiative properties under mixed-phase cloud conditions. These clouds were observed during the United States Department of Energy (US DOE) Atmospheric Radiation Measurement (ARM) Mixed-Phase Arctic Clouds Experiment (M-PACE) between September and November of 2004. In total, sixteen half hour time periods are reviewed due to their coincidence with radiosonde launches. Cloud liquid (ice) water paths are found to range between 11.0-366.4 (0.5-114.1) gm-2, and cloud physical thicknesses fall between 286-2075 m. Combined with temperature and hydrometeor size estimates, this information is used to calculate surface radiative flux densities using RRTMG, which are demonstrated to generally agree with measured flux densities from surface-based radiometric instrumentation. Errors in longwave flux density estimates are found to be largest for thin clouds, while shortwave flux density errors are generally largest for thicker clouds. A sensitivity study is performed to understand the impact of retrieval assumptions and uncertainties on derived surface radiation estimates. Cloud radiative forcing is calculated for all profiles, illustrating longwave dominance during this time of year, with net cloud forcing generally between 50 and 90 Wm-2.
JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, OctoberDecember 2000
Guo, Zhixiong "James"
JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, OctoberÂDecember 2000 Multidimensional are optical tomographyof tissue, remote sensing of oceansand atmospheres, laser material processing radiative heat transfer in participat- ing media in recent years. However, the analysis of radiative heat
Aqueous systems from first-principles : structure, dynamics and electron-transfer reactions
Sit, Patrick Hoi Land
2006-01-01T23:59:59.000Z
In this thesis, we show for the first time how it is possible to calculated fully from first-principles the diabatic free-energy surfaces of electron-transfer reactions. The excitation energy corresponding to the transfer ...
None
2011-04-25T23:59:59.000Z
Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.
Böcklin, Christoph, E-mail: boecklic@ethz.ch; Baumann, Dirk; Fröhlich, Jürg [Institute of Electromagnetic Fields, ETH Zurich, 8092 Zurich (Switzerland)
2014-02-14T23:59:59.000Z
A novel way to attain three dimensional fluence rate maps from Monte-Carlo simulations of photon propagation is presented in this work. The propagation of light in a turbid medium is described by the radiative transfer equation and formulated in terms of radiance. For many applications, particularly in biomedical optics, the fluence rate is a more useful quantity and directly derived from the radiance by integrating over all directions. Contrary to the usual way which calculates the fluence rate from absorbed photon power, the fluence rate in this work is directly calculated from the photon packet trajectory. The voxel based algorithm works in arbitrary geometries and material distributions. It is shown that the new algorithm is more efficient and also works in materials with a low or even zero absorption coefficient. The capabilities of the new algorithm are demonstrated on a curved layered structure, where a non-scattering, non-absorbing layer is sandwiched between two highly scattering layers.
Mass Transfer from Giant Donors
Pavlovskii, K
2014-01-01T23:59:59.000Z
The stability of mass transfer in binaries with convective giant donors remains an open question in modern astrophysics. There is a significant discrepancy between what the existing methods predict for a response to mass loss of the giant itself, as well as for the mass transfer rate during the Roche lobe overflow. Here we show that the recombination energy in the superadiabatic layer plays an important and hitherto unaccounted-for role in he donor's response to mass loss, in particular on its luminosity and effective temperature. Our improved optically thick nozzle method to calculate the mass transfer rate via $L_1$ allows us to evolve binary systems for a substantial Roche lobe overflow. We propose a new, strengthened criterion for the mass transfer instability, basing it on whether the donor experiences overflow through its outer Lagrangian point. We find that with the new criterion, if the donor has a well-developed outer convective envelope, the critical initial mass ratio for which a binary would evolv...
Atmospheric State, Cloud Microphysics and Radiative Flux
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Mace, Gerald
Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.
ELEG620: Solar Electric Systems University of Delaware, ECE Spring 2008 C. Honsberg Solar Radiation
Honsberg, Christiana
ELEG620: Solar Electric Systems University of Delaware, ECE Spring 2008 C. Honsberg Solar Radiation Solar Radiation: Effects of atmosphere, angular dependence of radiation, variation of solar radiation Â Calculation of Solar Radiation: Â· Estimate of intensity of solar radiation Â· Angular Dependence Â Solar Noon
structure calculations qualitatively reproduce the experimental observations. From the calculations interest in the kinetics and dynamics of electron transfer (ET) reac- tions, including reactions kinetics and dynamics studies: `how far is the electron transferred?' At first glance, this would appear
Multiphase flow calculation software
Fincke, James R. (Idaho Falls, ID)
2003-04-15T23:59:59.000Z
Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.
Lenert, Andrej
2012-01-01T23:59:59.000Z
The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...
Calculate viscosities for 355 liquids
Yaws, C.L.; Lin, Xiaoyan; Li Bu (Lamar Univ., TX (United States))
1994-04-01T23:59:59.000Z
Liquid viscosities are important factors in process design and operation. The viscosity of a liquid determines its flow properties, such as velocity and pressure drop. In addition, the heat- and mass-transfer characteristics of a liquid are affected by its viscosity. An equation can be used to calculate liquid viscosities as a function of temperature. In the accompanying table, regression coefficients are included for 355 compounds with five, six or seven carbon atoms--generally the most-widely used in the chemical and petroleum industries. To calculate the viscosity of a liquid at any temperature between its melting and critical points (T[sub min] and T[sub max]), use the following equation: log[sub 10] [eta][sub liq] = A + B/T + CT + DT[sup 2] where [eta][sub liq] = viscosity, cP, A,B,C and D = regression coefficients, and T = liquid temperature, K. Insert the temperature into the equation along with the corresponding regression coefficients from the table. The chemical formulae are listed by the number of carbon atoms.
Kandlikar, Satish
Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer
Gustavsen, Arlid; Kohler, Christian; Dalehaug, Arvid; Arasteh, Dariush
2008-12-01T23:59:59.000Z
This paper assesses the accuracy of the simplified frame cavity conduction/convection and radiation models presented in ISO 15099 and used in software for rating and labeling window products. Temperatures and U-factors for typical horizontal window frames with internal cavities are compared; results from Computational Fluid Dynamics (CFD) simulations with detailed radiation modeling are used as a reference. Four different frames were studied. Two were made of polyvinyl chloride (PVC) and two of aluminum. For each frame, six different simulations were performed, two with a CFD code and four with a building-component thermal-simulation tool using the Finite Element Method (FEM). This FEM tool addresses convection using correlations from ISO 15099; it addressed radiation with either correlations from ISO 15099 or with a detailed, view-factor-based radiation model. Calculations were performed using the CFD code with and without fluid flow in the window frame cavities; the calculations without fluid flow were performed to verify that the CFD code and the building-component thermal-simulation tool produced consistent results. With the FEM-code, the practice of subdividing small frame cavities was examined, in some cases not subdividing, in some cases subdividing cavities with interconnections smaller than five millimeters (mm) (ISO 15099) and in some cases subdividing cavities with interconnections smaller than seven mm (a breakpoint that has been suggested in other studies). For the various frames, the calculated U-factors were found to be quite comparable (the maximum difference between the reference CFD simulation and the other simulations was found to be 13.2 percent). A maximum difference of 8.5 percent was found between the CFD simulation and the FEM simulation using ISO 15099 procedures. The ISO 15099 correlation works best for frames with high U-factors. For more efficient frames, the relative differences among various simulations are larger. Temperature was also compared, at selected locations on the frames. Small differences was found in the results from model to model. Finally, the effectiveness of the ISO cavity radiation algorithms was examined by comparing results from these algorithms to detailed radiation calculations (from both programs). Our results suggest that improvements in cavity heat transfer calculations can be obtained by using detailed radiation modeling (i.e. view-factor or ray-tracing models), and that incorporation of these strategies may be more important for improving the accuracy of results than the use of CFD modeling for horizontal cavities.
ALARA Review of the Spallation Neutron Source Accumulator Ring and Transfer Lines
Haire, M.J.
2003-06-30T23:59:59.000Z
The Spallation Neutron Source (SNS) is designed to meet the growing need for new tools that will deepen our understanding in materials science, life science, chemistry, fundamental and nuclear physics, earth and environmental sciences, and engineering sciences. The SNS is an accelerator-based neutron-scattering facility that when operational will produce an average beam power of 2 MW at a repetition rate of 60 Hz. The accelerator complex consists of the front-end systems, which will include an ion source; a 1-GeV full-energy linear accelerator; a single accumulator ring and its transfer lines; and a liquid mercury target. This report documents an as-low-as-reasonably-achievable (ALARA) review of the accumulator ring and transfer lines at their early design stage. An ALARA working group was formed and conducted a review of the SNS ring and transfer lines at the {approx}25% complete design stage to help ensure that ALARA principles are being incorporated into the design. The radiological aspects of the SNS design criteria were reviewed against regulatory requirements and ALARA principles. Proposed features and measures were then reviewed against the SNS design criteria. As part of the overall review, the working group reviewed the design manual; design drawings and process and instrumentation diagrams; the environment, safety, and health manual; and other related reports and literature. The group also talked with SNS design engineers to obtain explanations of pertinent subject matter. The ALARA group found that ALARA principles are indeed being incorporated into the early design stage. Radiation fields have been characterized, and shielding calculations have been performed. Radiological issues are being adequately addressed with regard to equipment selection, access control, confinement structure and ventilation, and contamination control. Radiation monitoring instrumentation for worker and environment protection are also being considered--a good practice at this early design stage. The ring and transfer lines are being designed for hands-on maintenance. The SNS beam loss criteria, which determine radiation dose design, are a factor of {approx}30 lower than the lowest that has been achieved at any existing proton synchrotron and accumulator rings. This demonstrates that ALARA considerations are an important part of SNS design. A noteworthy example of the ALARA principal being incorporated into the SNS is the hybrid ring lattice design recently approved by the SNS change control process. The new lattice design increases calculated acceptance by about 50% and improves the expected collimator efficiency from 80 to 95%. As a result, the expected calculated beam loss rate, and resulting radiation dose rates, are significantly improved. Another major design change with ALARA implications was the change from an alpha to an omega configuration for the high-energy beam transport (HEBT) system, ring, and ring-to-target beam transport (RTBT) system. Because of this change, the ring and transfer lines will have crane coverage, eliminating the need for personnel to be near activated equipment for repair and removal. By using the crane, extensive shielding can be placed around highly radioactive equipment (e.g., collimators), and the equipment can be moved by remote control. As part of the change from an alpha to omega configuration, the tunnel width was increased by 2 ft. This increased width will allow easier access to failed equipment, reducing radiation exposure time to workers during maintenance and repair. In addition, a personnel entrance was added to the ring between the HEBT and RTBT so that personnel will not have to enter this area directly through the HEBT or RTBT. This addition will shorten the travel distance, and therefore the time, that personnel performing maintenance work on radioactive equipment will need to be in the area, reducing potential dose. In the RTBT beam line, a hatchway will be placed above the collimators and quad doublet magnets near the target to facilitate their removal. This design was chosen in lieu
Wireless energy transfer between anisotropic metamaterials shells
Díaz-Rubio, Ana; Carbonell, Jorge; Sánchez-Dehesa, José, E-mail: jsdehesa@upv.es
2014-06-15T23:59:59.000Z
The behavior of strongly coupled Radial Photonic Crystals shells is investigated as a potential alternative to transfer electromagnetic energy wirelessly. These sub-wavelength resonant microstructures, which are based on anisotropic metamaterials, can produce efficient coupling phenomena due to their high quality factor. A configuration of selected constitutive parameters (permittivity and permeability) is analyzed in terms of its resonant characteristics. The coupling to loss ratio between two coupled resonators is calculated as a function of distance, the maximum (in excess of 300) is obtained when the shells are separated by three times their radius. Under practical conditions an 83% of maximum power transfer has been also estimated. -- Highlights: •Anisotropic metamaterial shells exhibit high quality factors and sub-wavelength size. •Exchange of electromagnetic energy between shells with high efficiency is analyzed. •Strong coupling is supported with high wireless transfer efficiency. •End-to-end energy transfer efficiencies higher than 83% can be predicted.
22.01 Introduction to Ionizing Radiation, Fall 2003
Coderre, Jeffrey A.
Introduction to basic properties of ionizing radiations and their uses in medicine, industry, science, and environmental studies. Discusses natural and man-made radiation sources, energy deposition and dose calculations, ...
Model calculations of nuclear data for biologically-important elements
Chadwick, M.B.; Blann, M.; Reffo, G. [Lawrence Livermore National Lab., CA (United States); Young, P.G. [Los Alamos National Lab., NM (United States)
1994-05-01T23:59:59.000Z
We describe calculations of neutron-induced reactions on carbon and oxygen for incident energies up to 70 MeV, the relevant clinical energy in radiation neutron therapy. Our calculations using the FKK-GNASH, GNASH, and ALICE codes are compared with experimental measurements, and their usefulness for modeling reactions on biologically-important elements is assessed.
Jun'ichi Sato; Keisuke Sawada; Naofumi Ohnishi
2003-04-14T23:59:59.000Z
Two-dimensional numerical simulations of an accretion flow in a close binary system are performed by solving the Euler equations with radiative transfer. In the present study, the specific heat ratio is assumed to be constant while radiative cooling effect is included as a non-adiabatic process. The cooling effect of the disc is considered by discharging energy in the vertical directions from the top and bottom surfaces of the disc. We use the flux-limited diffusion approximation to calculate the radiative heat flux values. Our calculations show that a disc structure appears and the spiral shocks are formed on the disc. These features are similar to that observed in the case of an adiabatic gas with a lower specific heat ratio, $\\gamma=1.01$. It is found that when radiative cooling effect is accounted for, the mass of the disc becomes larger than that assuming $\\gamma=5/3$, and smaller than that assuming $\\gamma=1.01$. It is concluded that employing an adiabatic gas with a lower specific heat ratio is almost a valid assumption for simulating accretion disc with radiative cooling effect.
Hofstetter, K; Donna Beals, D; Ken Odell, K; Robert Eakle, R; Russell Huffman, R; Larry Harpring, L
2006-05-12T23:59:59.000Z
A unique radiation monitor has been developed for performing wide-area field surveys for radiation sources. This device integrates the real-time output of multiple radiation detectors into a hand-held personal computer (e.g., a PDA) containing an intuitive graphical user interface. An independent hardware module supplies high voltage to the detectors and contains a rapid sampling system for transferring the detector count rates through an interface to the PDA. The imbedded firmware can be changed for various applications using a programmable memory card. As presently configured, the instrument contains a series of Geiger-Mueller (GM) tubes in a flexible detector string. This linear array of multiple sensors can be used by US Coast Guard and Customs container inspection personnel to measure radiation intensity in stacks of transport containers where physical access is impeded.
Ionizing Radiation in Smoothed Particle Hydrodynamics
O. Kessel-Deynet; A. Burkert
2000-02-11T23:59:59.000Z
A new method for the inclusion of ionizing radiation from uniform radiation fields into 3D Smoothed Particle Hydrodynamics (SPHI) simulations is presented. We calculate the optical depth for the Lyman continuum radiation from the source towards the SPHI particles by ray-tracing integration. The time-dependent ionization rate equation is then solved locally for the particles within the ionizing radiation field. Using test calculations, we explore the numerical behaviour of the code with respect to the implementation of the time-dependent ionization rate equation. We also test the coupling of the heating caused by the ionization to the hydrodynamical part of the SPHI code.
Angular Ordering in Gluon Radiation
Jong B. Choi; Byeong S. Choi; Su K. Lee
2002-01-28T23:59:59.000Z
The assumption of angular ordering in gluon radiation is essential to obtain quantitative results concerning gluonic behaviors. In order to prove the validity of this assumption, we have applied our momentum space flux-tube formalism to check out the angular dependences of gluon radiation. We have calculated the probability amplitudes to get new gluon, and have found that the new gluon is generally expected to have the maximum amplitude when it is produced between the momentum directions of the last two partons.
Solar Radiation and Asteroidal Motion
Jozef Klacka
2000-09-07T23:59:59.000Z
Effects of solar wind and solar electromagnetic radiation on motion of asteroids are discussed. The results complete the statements presented in Vokrouhlick\\'{y} and Milani (2000). As for the effect of electromagnetic radiation, the complete equation of motion is presented to the first order in $v/c$ -- the shape of asteroid (spherical body is explicitly presented) and surface distribution of albedo should be taken into account. Optical quantities must be calculated in proper frame of reference.
Radiation Shielding for Fusion Reactors
Santoro, R.T.
1999-10-01T23:59:59.000Z
Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shielding. Radiation transport calculations are essential for predicting and confirming the nuclear performance of the reactor and, as such, must be an essential part of the reactor design process. Development and optimization of reactor components from the first wall and primary shielding to the penetrations and containment shielding must be carried out in a sensible progression. Initial results from one-dimensional transport calculations are used for scoping studies and are followed by detailed two- and three-dimensional analyses to effectively characterize the overall radiation environment. These detail model calculations are essential for accounting for the radiation leakage through ports and other penetrations in the bulk shield. Careful analysis of component activation and radiation damage is cardinal for defining remote handling requirements, in-situ replacement of components, and personnel access at specific locations inside the reactor containment vessel. Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shielding. Radiation transport calculations are essential for predicting and confirming the nuclear performance of the reactor and, as such, must be an essential part of the reactor design process. Development and optimization of reactor components from the first wall and primary shielding to the penetrations and containment shielding must be carried out in a sensible progression. Initial results from one-dimensional transport calculations are used for scoping studies and are followed by detailed two- and three-dimensional analyses to effectively characterize the overall radiation environment. These detail model calculations are essential for accounting for the radiation leakage through ports and other penetrations in the bulk shield. Careful analysis of component activation and radiation damage is cardinal for defining remote handling requirements, in-situ replacement of components, and personnel access at specific locations inside the reactor containment vessel.
Standard Test Method for Measuring Heat Transfer Rate Using a Thin-Skin Calorimeter
American Society for Testing and Materials. Philadelphia
2005-01-01T23:59:59.000Z
1.1 This test method covers the design and use of a thin metallic calorimeter for measuring heat transfer rate (also called heat flux). Thermocouples are attached to the unexposed surface of the calorimeter. A one-dimensional heat flow analysis is used for calculating the heat transfer rate from the temperature measurements. Applications include aerodynamic heating, laser and radiation power measurements, and fire safety testing. 1.2 Advantages 1.2.1 Simplicity of ConstructionThe calorimeter may be constructed from a number of materials. The size and shape can often be made to match the actual application. Thermocouples may be attached to the metal by spot, electron beam, or laser welding. 1.2.2 Heat transfer rate distributions may be obtained if metals with low thermal conductivity, such as some stainless steels, are used. 1.2.3 The calorimeters can be fabricated with smooth surfaces, without insulators or plugs and the attendant temperature discontinuities, to provide more realistic flow conditions for ...
Triplett, C.E.
1996-12-01T23:59:59.000Z
This thesis presents the results of an experimental investigation of natural convection heat transfer in a staggered array of heated cylinders, oriented horizontally within a rectangular enclosure. The main purpose of this research was to extend the knowledge of heat transfer within enclosed bundles of spent nuclear fuel rods sealed within a shipping or storage container. This research extends Canaan`s investigation of an aligned array of heated cylinders that thermally simulated a boiling water reactor (BWR) spent fuel assembly sealed within a shipping or storage cask. The results are presented in terms of piecewise Nusselt-Rayleigh number correlations of the form Nu = C(Ra){sup n}, where C and n are constants. Correlations are presented both for individual rods within the array and for the array as a whole. The correlations are based only on the convective component of the heat transfer. The radiative component was calculated with a finite-element code that used measured surface temperatures, rod array geometry, and measured surface emissivities as inputs. The correlation results are compared to Canaan`s aligned array results and to other studies of natural convection in horizontal tube arrays.
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 Molecular dynamics methods in
Maruyama, Shigeo
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 2.13.7 Molecular dynamics methods in microscale heat transfer Shigeo Maruyama A. Introduction In normal heat transfer and fluid flow calculations of molecules. This situation is approached in microscale heat transfer and fluid flow. Molecular level
Surface Power Radiative Cooling Tests
Vaughn, Jason; Schneider, Todd [Environmental Effects Branch, EM50, NASA Marshall Space Flight Center, AL 35812 (United States)
2006-01-20T23:59:59.000Z
Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. {approx}5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.
Genomic instability and bystander effects induced by high-LET radiation Eric J Hall*,1
of the radiobiological effects of high- linear energy transfer (LET) radiation is essential for radiation protectionGenomic instability and bystander effects induced by high-LET radiation Eric J Hall*,1 and Tom K, it has always been accepted that the deleterious effects of ionizing radiation, such as mutation
ON THE SOLAR RADIATION BUDGET AND THE CLOUD ABSORPTION ANOMALY DEBATE
Li, Zhanqing
ON THE SOLAR RADIATION BUDGET AND THE CLOUD ABSORPTION ANOMALY DEBATE ZHANQING LI Department-of-the-art radiative transfer models. 1. Introduction Solar radiation is the ultimate source of energy for the planet of solar radiation, which is unfortunately still fraught with large uncertainties (Wild et al. 1995; Li et
Fultz, Brent T. (Berkeley, CA)
1983-01-01T23:59:59.000Z
Apparatus is provided for detecting radiation such as gamma rays and X-rays generated in backscatter Mossbauer effect spectroscopy and X-ray spectrometry, which has a large "window" for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.
Fultz, B.T.
1980-12-05T23:59:59.000Z
Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.
Gravitational Radiation From Cosmological Turbulence
Arthur Kosowsky; Andrew Mack; Tinatin Kahniashvili
2002-06-27T23:59:59.000Z
An injection of energy into the early Universe on a given characteristic length scale will result in turbulent motions of the primordial plasma. We calculate the stochastic background of gravitational radiation arising from a period of cosmological turbulence, using a simple model of isotropic Kolmogoroff turbulence produced in a cosmological phase transition. We also derive the gravitational radiation generated by magnetic fields arising from a dynamo operating during the period of turbulence. The resulting gravitational radiation background has a maximum amplitude comparable to the radiation background from the collision of bubbles in a first-order phase transition, but at a lower frequency, while the radiation from the induced magnetic fields is always subdominant to that from the turbulence itself. We briefly discuss the detectability of such a signal.
The structure and radiation spectra of illuminated accretion discs in AGN. I. Moderate illumination
Rózanska, A R; Czerny, B; Collin, S
2002-01-01T23:59:59.000Z
We present detailed computations of the vertical structure of an accretion disc illuminated by hard X-ray radiation with the code {\\sc titan-noar} suitable for Compton thick media. The energy generated via accretion is dissipated partially in the cold disc as well as in the X-ray source. We study the differences between the case where the X-ray source is in the form of a lamp post above the accretion disc and the case of a heavy corona. We consider radiative heating via Comptonization together with heating via photo-absorption on numerous heavy elements as carbon, oxygen, silicon, iron. The transfer in lines is precisely calculated. A better description of the heating/cooling through the inclusion of line transfer, a correct description of the temperature in the deeper layers, a correct description of the entire disc vertical structure, as well as the study of the possible coronal pressure effect, constitute an improvement in comparison to previous works. We show that exact calculations of hydrostatic equilib...
Townsend, H.E.; Barbanti, G.
1994-03-01T23:59:59.000Z
A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool. 6 figures.
Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.
2010-07-18T23:59:59.000Z
In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 10-15 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper proposes that there may be reliable CFD approaches to the transfer cask problem, specifically coupled steady-state solvers or unsteady simulations; however, both of these solutions take significant computational effort. Segregated (uncoupled) steady state solvers that were tested did not accurately capture the flow field and heat transfer distribution in this application. Mesh resolution, turbulence modeling, and the tradeoff between steady state and transient solutions are addressed. Because of the critical nature of this application, the need for new experiments at representative scales is clearly demonstrated.
Mohr, R. J.; Fowler, R.
HIGEE MASS TRANSFER R.J. Mohr and R. Fowler GLITSCH, INC. Dallas, Texas ABSTRACT Distillation, absorption, and gas stripping have traditionally been performed in tall columns utilizing trays or packing. Columns perform satisfactorily... transfer system which utilizes a rotating bed of packing to achieve high efficiency separations, and consequent reduction in size and weight. INTRODUCTION HIGEE is probably one of the most interesting developments in mass transfer equipment made...
On the design of heat-transfer probes
Brich, M.A.; Ganzha, V.L.; Saxena, S.C. [Univ. of Illinois, Chicago, IL (United States)] [Univ. of Illinois, Chicago, IL (United States)
1997-03-01T23:59:59.000Z
Saxena and coworkers have reported heat-transfer coefficient values for magnetofluidized beds using electrically heated heat-transfer probes. Here, a two-dimensional heat-transfer model is employed to investigate the influence of significant design features on measured parameters. Numerical calculations reveal that the thermal conductivity of the probe material has an insignificant contribution but the material of end caps and relative sizes and locations of the probe and heater appreciably influence the heat-transfer rates through end-conduction.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
MTAXX-XXX 1 MATERIAL TRANSFER AGREEMENT for Manufacturing Demonstration Facility and Carbon Fiber Technology Facility In order for the RECIPIENT to obtain materials, the RECIPIENT...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
July 29, 2013 Scientists gain first quantitative insights into electron transfer from minerals to microbes Scientists have gained the first quantitative insights into electron...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Advanced Research Projects Agency-Energy (ARPA-E) Oil & Gas Technology Transfer Initiatives USEFUL LINKS Association of University Technology Managers (AUTM) Federal Laboratory...
Weronick, R.; Hassan, I.D. [Raytheon Engineers and Constructors, Lyndhurst, NJ (United States)
1996-11-01T23:59:59.000Z
This paper discusses bus transfer schemes and the methodology used in modeling and analysis. Due to the unavailability of generic acceptance criteria, simulations were performed to analyze the actual fast bus transfer operations at four operating nuclear power generating stations. Sample simulation results illustrating the transient variations in motors currents and torques are included. The analyses were performed to ensure that motors and other rotating parts are not subjected to excessive or accumulated stresses caused by bus transfer operations. A summary of the experience gained in the process of performing this work and suggested bus transfer acceptance criteria are also presented.
Broader source: Energy.gov [DOE]
As DOE facilities become excess, many that are radioactively and/or chemically contaminated will become candidate for transfer to DOE-EM for deactivation and decommissioning.
About convective heat transfer in geothermal systems
Pashkevich, R.I. [Kamchatsky Complex Department of NIPIgeotherm Institute, Petropavlovsk-Kamchatsky (Russian Federation)
1996-12-31T23:59:59.000Z
The interphase fluid-rock heat exchange in convective beat transfer in geothermal systems is investigated Nonlinear model of interphase heat exchange is suggested. Calculation for one dimension case and comparison with known Anzelius-Schumann solution is presented Generalized type block heat transfer model is formulated. The model is adequate for case of geothermal systems and reservoir when a rock block size is comparable with filtration path length. Criterion equations for nonstationary coefficients of interphase heat exchange we presented these equations were obtained in laboratory experiments with diorites.
Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in a
Oak Ridge National Laboratory
Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in a Brazed Plate and Condensation Heat Transfer Performance of Flammable Refrigerants in a Brazed Plate Heat Exchanger Sheila C ........................................................... 8 3. Average relative difference (%) in calculated heat transfer rates for refrigerants and HTF
RADIATION SAFETY TRAINING MANUAL Radiation Safety Office
Sibille, Etienne
protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. OVERVIEW OF REGULATIONS, PROTECTION STANDARDS, AND RADIATION SAFETY ORGANIZATION.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 V. BASIC RADIATION PROTECTION PRINCIPLES
REMOTE AREA RADIATION MONITORING (RARM) ALTERNATIVES ANALYSIS
NELSON RL
2008-07-18T23:59:59.000Z
The Remote Area Radiation Monitoring (RARM) system will be used to provide real-time radiation monitoring information to the operations personnel during tank retrieval and transfer operations. The primary focus of the system is to detect potential anomalous (waste leaks) or transient radiological conditions. This system will provide mobile, real-time radiological monitoring, data logging, and status at pre-selected strategic points along the waste transfer route during tank retrieval operations. The system will provide early detection and response capabilities for the Retrieval and Closure Operations organization and Radiological Control personnel.
Heat transfer model of above and underground insulated piping systems
Kwon, K.C.
1998-07-01T23:59:59.000Z
A simplified heat transfer model of above and underground insulated piping systems was developed to perform iterative calculations for fluid temperatures along the entire pipe length. It is applicable to gas, liquid, fluid flow with no phase change. Spreadsheet computer programs of the model have been developed and used extensively to perform the above calculations for thermal resistance, heat loss and core fluid temperature.
Geothermal Life Cycle Calculator
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Sullivan, John
This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.
Geothermal Life Cycle Calculator
Sullivan, John
2014-03-11T23:59:59.000Z
This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.
M. P. Rekalo; E. Tomasi-Gustafsson
2001-05-02T23:59:59.000Z
We calculate polarization phenomena for virtual Compton scattering on protons, at relatively large momentum transfer 1 GeV$^2$ $\\le -q^2\\le$ 5 GeV$^2$ on the basis of a model for $\\gamma^*+ p\\to \\gamma+p$ with two main contributions: $\\pi^0$-exchange in $t-$channel and $\\Delta$-excitation in $s$-channel. This model applies from threshold to $\\Delta$ region. The parameters entering in this model, such as coupling constants and electromagnetic form factors are well known. The analyzing powers for $\\gamma^*+\\vec p\\to \\gamma+ p$ and the components of the final proton polarization in $\\gamma^*+ p\\to \\gamma+ \\vec p$ are large in absolute value and show strong sensitivity to $\\pi\\bigotimes\\Delta$ interference. These results can be applied to the calculation of radiative corrections to polarization phenomena in elastic $ep$-scattering.
Radiation dosimetry and medical physics calculations using MCNP 5
Redd, Randall Alex
2004-09-30T23:59:59.000Z
by 6.02E-10 to convert the units from MeV g-1 to J kg-1 (Gy). The mass within the cell was determined by multiplying the density of material in the cell by the volume of the cell. Results The radial and angular anisotropic dose distributions... response for photons of energy 33 keV, 48 keV, 100 keV, 248 keV, 662 keV, and 1.25 MeV were determined as energy absorbed in the TLD, which was assumed to be proportional to light output. Neutron response for neutrons with energies of 0.0253 eV, 1 eV...
Multigroup Radiation Transport in Supernova Light Curve Calculations |
Office of Scientific and Technical Information (OSTI)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilAElectronicCurves | SciTechLagrangeEnergy, Office of ScientificUS DeptUS
Measurements and model calculations of radiative fluxes for the Cabauw
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals from a NewCuneo Matthew1, 20121 H( 7radialMHD
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation Protection Regulations: The Federal Regulation
11th International Conference of Radiation Research
NONE
1999-07-18T23:59:59.000Z
Topics discussed in the conference included the following: Radiation Physics, Radiation Chemistry and modelling--Radiation physics and dosimetry; Electron transfer in biological media; Radiation chemistry; Biophysical and biochemical modelling; Mechanisms of DNA damage; Assays of DNA damage; Energy deposition in micro volumes; Photo-effects; Special techniques and technologies; Oxidative damage. Molecular and cellular effects-- Photobiology; Cell cycle effects; DNA damage: Strand breaks; DNA damage: Bases; DNA damage Non-targeted; DNA damage: other; Chromosome aberrations: clonal; Chromosomal aberrations: non-clonal; Interactions: Heat/Radiation/Drugs; Biochemical effects; Protein expression; Gene induction; Co-operative effects; ``Bystander'' effects; Oxidative stress effects; Recovery from radiation damage. DNA damage and repair -- DNA repair genes; DNA repair deficient diseases; DNA repair enzymology; Epigenetic effects on repair; and Ataxia and ATM.
Infrared radiation of SF sub 6 and its application to gas-filled double-pane windows
Reilly, S.; Rubin, M. (Lawrence Berkeley Lab., CA (USA)); Tuntomo, A.; Tien, C.L. (California Univ., Irvine, CA (USA). Dept. of Mechanical Engineering)
1990-01-01T23:59:59.000Z
Interest in using sulfur hexafluoride (SF{sub 6}) as a gas-fill in multipane windows has raised questions concerning the calculation of heat transfer rates through such windows. The infrared absorption characteristics of this gas make the heat transfer analysis much more complicated. In order to account for the absorption effect, the authors measured the spectral absorptivity of several infrared-active bands of sulfur hexafluroide at low resolution and a temperature of 298 K. The authors correlated the spectral absorption data with Edwards exponential wide-band model and with the Elasser narrow-band model, and incorporated, the wide-band model into a one-dimensional, finite-element heat transfer model. The finite-element heat transfer model considered combined conduction and radiation effects in a double-pane window, and was used to evaluate the overall heat transfer coefficients of double-pane windows filled with SF{sub 6}, CO{sub 2}, or air. The numerical results show good agreement with the experimental results.
Broader source: Energy.gov [DOE]
This calculator estimates the amount of carbon emissions you and members of your household are responsible for. It does not include emissions associated with your work or getting to work if you commute by public transportation. It was developed by IEEE Spectrum magazine.
PROPOSED RESIDENTIAL ALTERNATIVE CALCULATION
PROPOSED RESIDENTIAL ALTERNATIVE CALCULATION MANUAL (ACM) APPROVAL METHOD for the 2013 2012 CEC400201200715DAY #12;201308 Residential ACM Approval Manual 2-2 1. Overview Minimum Modeling Capabilities 1. Overview This Manual explains the requirements for approval of residential Alternative
TOPAZ2D heat transfer code users manual and thermal property data base
Shapiro, A.B.; Edwards, A.L.
1990-05-01T23:59:59.000Z
TOPAZ2D is a two dimensional implicit finite element computer code for heat transfer analysis. This user's manual provides information on the structure of a TOPAZ2D input file. Also included is a material thermal property data base. This manual is supplemented with The TOPAZ2D Theoretical Manual and the TOPAZ2D Verification Manual. TOPAZ2D has been implemented on the CRAY, SUN, and VAX computers. TOPAZ2D can be used to solve for the steady state or transient temperature field on two dimensional planar or axisymmetric geometries. Material properties may be temperature dependent and either isotropic or orthotropic. A variety of time and temperature dependent boundary conditions can be specified including temperature, flux, convection, and radiation. Time or temperature dependent internal heat generation can be defined locally be element or globally by material. TOPAZ2D can solve problems of diffuse and specular band radiation in an enclosure coupled with conduction in material surrounding the enclosure. Additional features include thermally controlled reactive chemical mixtures, thermal contact resistance across an interface, bulk fluid flow, phase change, and energy balances. Thermal stresses can be calculated using the solid mechanics code NIKE2D which reads the temperature state data calculated by TOPAZ2D. A three dimensional version of the code, TOPAZ3D is available. The material thermal property data base, Chapter 4, included in this manual was originally published in 1969 by Art Edwards for use with his TRUMP finite difference heat transfer code. The format of the data has been altered to be compatible with TOPAZ2D. Bob Bailey is responsible for adding the high explosive thermal property data.
Photon Radiation in a Heat Bath
P V Landshoff; J C Taylor
1994-04-26T23:59:59.000Z
We discuss the bremsstrahlung of photons into a heat bath, and calculate from first principles the energy radiated. Even to lowest order the spectrum of the radiation at low frequency is no more singular than at zero temperature. In addition to the obvious contributions, this spectrum includes terms associated with fluctuations. [Revised version has additional explanations
Gluon Radiation and Parton Energy Loss
Alexander Kovner; Urs Achim Wiedemann
2003-04-15T23:59:59.000Z
The propagation of hard partons through spatially extended matter leads to medium-modifications of their fragmentation pattern. Here, we review the current status of calculations of the corresponding medium-induced gluon radiation, and how this radiation affects hadronic observables at collider energies.
Neirotti, Juan Pablo
* Fundamental processes of mass transfer * Design principles of heat exchangers * Fundamentals of radiant heat * a knowledge of the fundamentals and practical applications of radiative heat transfer * a knowledge of pipe solving * Study skills * Time management Indicative Module Content: Heat Transfer (Dr. John Brammer) Heat
Gravitational Radiation in Noncommutative Gravity
A. Jahan; N. Sadeghnezhad
2014-11-24T23:59:59.000Z
The gravitational radiation power of a binary system in a noncommutative space is derived and it's rate of the period decrease is calculated to first order in noncommutativity parameter. By comparing the theoretical results with the observational data of the binary pulsar PSR 1913+16, we find a bound on the noncommutativity parameter.
POSITION DESCRIPTION 2012 TRANSFER MENTOR
POSITION DESCRIPTION 2012 TRANSFER MENTOR TRANSFER MENTOR AS A STAFF MEMBER Thank you for your interest in the Transfer Mentor position with Orientation and Transition Programs' (OTP) Transfer Mentoring Program. The Transfer Mentor (TM) is a member of the Orientation and Transition Programs' staff
SWAMI II technology transfer plan
Ward, C.R.; Peterson, K.D.; Harpring, L.J.; Immel, D.M.; Jones, J.D.; Mallet, W.R.
1995-12-31T23:59:59.000Z
Thousands of drums of radioactive/hazardous/mixed waste are currently stored at DOE sites throughout US; they are stored in warehouse facilities on an interim basis, pending final disposition. Recent emphasis on anticipated decommissioning of facilities indicates that many more drums of waste will be generated, requiring additional storage. Federal and state regulations dictate that hazardous waste covered by RCRA be inspected periodically for container degradation and to verify inventories. All known DOE waste storage facilities are currently inspected manually. A system to perform robotic inspection of waste drums is under development by the SRTC Robotics Group of WSRC; it is called the Stored Waste Autonomous Mobile Inspector (SWAMI). The first version, SWAMI I, was developed by the Savannah River Technology Center (SRTC) as a proof of principle system for autonomous inspection of drums in a warehouse. SWAMI I was based on the Transitions Research Corporation (TRC) HelpMate mobile robot. TRC modified the Helpmate to navigate in aisles of drums. SRTC added subsystems to SWAMI I to determine its position in open areas, read bar code labels on the drums up to three levels high, capture images of the drums and perform a radiation survey of the floor in the aisles. The radiation survey was based on SRTC patented technology first implemented on the Semi-Intelligent Mobile Observing Navigator (SIMON). The radiation survey is not essential for the inspection of drums, but is an option that can increase the utility and effectiveness of SWAMI in warehouses with radioactive and/or mixed waste. All the sensors on SWAMI I were fixed on the vehicle. From the success of SWAMI I, a second version, SWAMI II, was developed; it will be evaluated at Fernald and tested with two other mobile robots. Intent is to transfer the technology developed for SWAMI I and II to industry so that it can supply additional units for purchase for drum inspection.
Heat Transfer and Cooling Techniques at Low Temperature
Baudouy, B
2014-01-01T23:59:59.000Z
The first part of this chapter gives an introduction to heat transfer and cooling techniques at low temperature. We review the fundamental laws of heat transfer (conduction, convection and radiation) and give useful data specific to cryogenic conditions (thermal contact resistance, total emissivity of materials and heat transfer correlation in forced or boiling flow for example) used in the design of cooling systems. In the second part, we review the main cooling techniques at low temperature, with or without cryogen, from the simplest ones (bath cooling) to the ones involving the use of cryocoolers without forgetting the cooling flow techniques.
Heat transfer between elastic solids with randomly rough surfaces
B. N. J. Persson; B. Lorenz; A. I. Volokitin
2009-08-27T23:59:59.000Z
We study the heat transfer between elastic solids with randomly rough surfaces. We include both the heat transfer from the area of real contact, and the heat transfer between the surfaces in the noncontact regions. We apply a recently developed contact mechanics theory, which accounts for the hierarchical nature of the contact between solids with roughness on many different length scales. For elastic contact, at the highest (atomic) resolution the area of real contact typically consists of atomic (nanometer) sized regions, and we discuss the implications of this for the heat transfer. For solids with very smooth surfaces, as is typical in many modern engineering applications, the interfacial separation in the non-contact regions will be very small, and for this case we show the importance of the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies.
Not Available
1994-01-01T23:59:59.000Z
This document, Technology Transfer 94, is intended to communicate that there are many opportunities available to US industry and academic institutions to work with DOE and its laboratories and facilities in the vital activity of improving technology transfer to meet national needs. It has seven major sections: Introduction, Technology Transfer Activities, Access to Laboratories and Facilities, Laboratories and Facilities, DOE Office, Technologies, and an Index. Technology Transfer Activities highlights DOE`s recent developments in technology transfer and describes plans for the future. Access to Laboratories and Facilities describes the many avenues for cooperative interaction between DOE laboratories or facilities and industry, academia, and other government agencies. Laboratories and Facilities profiles the DOE laboratories and facilities involved in technology transfer and presents information on their missions, programs, expertise, facilities, and equipment, along with data on whom to contact for additional information on technology transfer. DOE Offices summarizes the major research and development programs within DOE. It also contains information on how to access DOE scientific and technical information. Technologies provides descriptions of some of the new technologies developed at DOE laboratories and facilities.
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary900Steep Slope Calculator Estimates Cooling and Heating
Radiation Detection Computational Benchmark Scenarios
Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.
2013-09-24T23:59:59.000Z
Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.
Cosmology calculations almost without general relativity
Thomas F. Jordan
2004-12-08T23:59:59.000Z
The Friedmann equation is derived for a Newtonian universe. Changing mass density to energy density gives exactly the Friedmann equation of general relativity. Accounting for work done by pressure then yields the two Einstein equations that govern the expansion of the universe. Descriptions and explanations of radiation pressure and vacuum pressure are added to complete a basic kit of cosmology tools. It provides a basis for teaching cosmology to undergraduates in a way that quickly equips them to do basic calculations. This is demonstrated with calculations involving: characteristics of the expansion for densities dominated by radiation, matter, or vacuum; the closeness of the density to the critical density; how much vacuum energy compared to matter energy is needed to make the expansion accelerate; and how little is needed to make it stop. Travel time and luninosity distance are calculated in terms of the redshift and the densities of matter and vacuum energy, using a scaled Friedmann equation with the constant in the curvature term determined by matching with the present values of the Hubble parameter and energy density. General relativity is needed only for the luminosity distance, to describe how the curvature of space, determined by the energy density, can change the intensity of light by changing the area of the sphere to which the light has spread. Thirty-one problems are included.
Using Graphical Representations to Support the Calculation of Infusion Parameters
Subramanian, Sriram
Using Graphical Representations to Support the Calculation of Infusion Parameters Sandy J. J. Gould in which participants were asked to solve a num- ber of infusion parameter problems that were represented representations transfer to actual workplace settings. Keywords: Graphical reasoning, infusion pumps, re
Hunt, A.J.
1983-09-13T23:59:59.000Z
The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.
Hunt, Arlon J. (Oakland, CA)
1983-01-01T23:59:59.000Z
The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.
New equation calculates thermal conductivities of C[sub 1]-C[sub 4] gases
Yaws, C.L.; Lin, X.; Bu, L.; Nijhawan, S. (Lamar Univ., Beaumont, TX (United States))
1994-04-18T23:59:59.000Z
In the design of heat exchangers, heat-transfer coefficients are commonly calculated for individual items. These calculations require knowledge of the thermal conductivities of the species involved. The calculation require knowledge of the thermal conductivities of the species involved. The calculation of the overall heat-transfer coefficient for a heat exchanger also requires thermal conductivity data for the individual species. In fact, thermal conductivity is the fundamental property involved in heat transfer. Ordinarily, thermal conductivities are either measured experimentally or estimated using complex correlations and models. Engineers must search existing literature for the values needed. Here, a compilation of thermal conductivity data for gases is presented for a wide temperature range. Using these data with the accompanying equation will enable engineers to quickly determine values at the desired temperatures. The results are provided in an easy-to-use tabular format, which is especially helpful for rapid calculations using a personal computer or hand-held calculator.
Source storage and transfer cask: Users Guide
Eccleston, G.W.; Speir, L.G.; Garcia, D.C.
1985-04-01T23:59:59.000Z
The storage and shield cask for the dual californium source is designed to shield and transport up to 3.7 mg (2 Ci) of /sup 252/Cf. the cask meets Department of Transportation (DOT) license requirements for Type A materials (DOT-7A). The cask is designed to transfer sources to and from the Flourinel and Fuel Storage (FAST) facility delayed-neutron interrogator. Californium sources placed in the cask must be encapsulated in the SR-CF-100 package and attached to Teleflex cables. The cask contains two source locations. Each location contains a gear box that allows a Teleflex cable to be remotely moved by a hand crank into and out of the cask. This transfer procedure permits sources to be easily removed and inserted into the delayed-neutron interrogator and reduces personnel radiation exposure during transfer. The radiation dose rate with the maximum allowable quantity of californium (3.7 mg) in the cask is 30 mR/h at the surface and less than 2 mR/h 1 m from the cask surface. This manual contains information about the cask, californium sources, describes the method to ship the cask, and how to insert and remove sources from the cask. 28 figs.
Random number stride in Monte Carlo calculations
Hendricks, J.S.
1990-01-01T23:59:59.000Z
Monte Carlo radiation transport codes use a sequence of pseudorandom numbers to sample from probability distributions. A common practice is to start each source particle a predetermined number of random numbers up the pseudorandom number sequence. This number of random numbers skipped between each source particles the random number stride, S. Consequently, the jth source particle always starts with the j{center dot}Sth random number providing correlated sampling'' between similar calculations. A new machine-portable random number generator has been written for the Monte Carlo radiation transport code MCNP providing user's control of the random number stride. First the new MCNP random number generator algorithm will be described and then the effects of varying the stride will be presented. 2 refs., 1 fig.
Accurate and Approximate Calculations of Raman Scattering in the Atmosphere of Neptune
Sromovsky, Lawrence
2015-01-01T23:59:59.000Z
Raman scattering by H$_2$ in Neptune's atmosphere has significant effects on its reflectivity for $\\lambda 0.5 $\\mu$m, producing baseline decreases of $\\sim$ 20% in a clear atmosphere and $\\sim$ 10% in a hazy atmosphere. Here we present the first radiation transfer algorithm that includes both polarization and Raman scattering and facilitates computation of spatially resolved spectra. New calculations show that Cochran and Trafton's (1978, Astrophys. J. 219, 756-762) suggestion that light reflected in the deep CH$_4$ bands is mainly Raman scattered is not valid for current estimates of the CH$_4$vertical distribution, which implies only a 4% Raman contribution. Comparisons with IUE, HST, and groundbased observations confirm that high altitude haze absorption is reducing Neptune's geometric albedo by $\\sim$6% in the 0.22-0.26 $\\mu$m range and by $\\sim$13% in the 0.35-0.45 $\\mu$m range. We used accurate calculations to evaluate several approximations of Raman scattering. The Karkoschka (1994, Icarus 111, ...
Bernard F Schutz
2000-03-16T23:59:59.000Z
Gravity is one of the fundamental forces of Nature, and it is the dominant force in most astronomical systems. In common with all other phenomena, gravity must obey the principles of special relativity. In particular, gravitational forces must not be transmitted or communicated faster than light. This means that when the gravitational field of an object changes, the changes ripple outwards through space and take a finite time to reach other objects. These ripples are called gravitational radiation or gravitational waves. This article gives a brief introduction to the physics of gravitational radiation, including technical material suitable for non-specialist scientists.
Ames Lab 101: Technology Transfer
Covey, Debra
2012-08-29T23:59:59.000Z
Ames Laboratory Associate Laboratory Director, Sponsored Research Administration, Debra Covey discusses technology transfer. Covey also discusses Ames Laboratory's most successful transfer, lead-free solder.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
64 Ni+ 64 Ni Strong entrance-channel dependence of fusion enhancement Beckerman et al., PRL 45, 1472 (1980), PRC 25, 837 (1982) Coupling of transfer channels, in addition to...
Infrared absorption spectra, radiative efficiencies, and global warming potentials
Wirosoetisno, Djoko
Infrared absorption spectra, radiative efficiencies, and global warming potentials of newly.mdpi.com/journal/atmosphere Article Infrared Absorption Spectra, Radiative Efficiencies, and Global Warming Potentials of Newly of 600Â1730 cm-1 . These spectra are then used to calculate the radiative efficiencies and global warming
Synchrotron radiation from massless charge
Gal'tsov, D V
2015-01-01T23:59:59.000Z
Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some general arguments suggest that strictly massless charge does not not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for {\\em ab initio} massless particle of zero spin. Provided $E^2\\gg eH$, the maximum in the spectrum is shown to be at $\\hbar \\omega=E/3$, and the average photon energy is $4E/9$. The normalized spectrum is universal, depending neither on $E$ nor on $H$. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Our results are consistent with the view (sup...
INSTITUTE OF NUCLEAR TECHNOLOGY RADIATION PROTECTION
INSTITUTE OF NUCLEAR TECHNOLOGY RADIATION PROTECTION ANNUAL REPORT 2005 - 2006 #12;2 #12;3 ANNUAL. Papazoglou #12;5 PREFACE The Institute has continued transferring know how from Nuclear Technology to other of the Institute page 34 7. Publications page 36 8. Research Projects page 72 #12;4 ORGANISATIONAL CHART 2006
Pannala, S; D'Azevedo, E; Zacharia, T
2002-02-26T23:59:59.000Z
The goal of the radiation modeling effort was to develop and implement a radiation algorithm that is fast and accurate for the underhood environment. As part of this CRADA, a net-radiation model was chosen to simulate radiative heat transfer in an underhood of a car. The assumptions (diffuse-gray and uniform radiative properties in each element) reduce the problem tremendously and all the view factors for radiation thermal calculations can be calculated once and for all at the beginning of the simulation. The cost for online integration of heat exchanges due to radiation is found to be less than 15% of the baseline CHAD code and thus very manageable. The off-line view factor calculation is constructed to be very modular and has been completely integrated to read CHAD grid files and the output from this code can be read into the latest version of CHAD. Further integration has to be performed to accomplish the same with STAR-CD. The main outcome of this effort is to obtain a highly scalable and portable simulation capability to model view factors for underhood environment (for e.g. a view factor calculation which took 14 hours on a single processor only took 14 minutes on 64 processors). The code has also been validated using a simple test case where analytical solutions are available. This simulation capability gives underhood designers in the automotive companies the ability to account for thermal radiation - which usually is critical in the underhood environment and also turns out to be one of the most computationally expensive components of underhood simulations. This report starts off with the original work plan as elucidated in the proposal in section B. This is followed by Technical work plan to accomplish the goals of the project in section C. In section D, background to the current work is provided with references to the previous efforts this project leverages on. The results are discussed in section 1E. This report ends with conclusions and future scope of work in section F.
The structure and radiation spectra of illuminated accretion discs in AGN. I. Moderate illumination
A. Ró?a?ska; A. -M. Dumont; B. Czerny; S. Collin
2002-02-12T23:59:59.000Z
We present detailed computations of the vertical structure of an accretion disc illuminated by hard X-ray radiation with the code {\\sc titan-noar} suitable for Compton thick media. The energy generated via accretion is dissipated partially in the cold disc as well as in the X-ray source. We study the differences between the case where the X-ray source is in the form of a lamp post above the accretion disc and the case of a heavy corona. We consider radiative heating via Comptonization together with heating via photo-absorption on numerous heavy elements as carbon, oxygen, silicon, iron. The transfer in lines is precisely calculated. A better description of the heating/cooling through the inclusion of line transfer, a correct description of the temperature in the deeper layers, a correct description of the entire disc vertical structure, as well as the study of the possible coronal pressure effect, constitute an improvement in comparison to previous works. We show that exact calculations of hydrostatic equilibrium and determination of the disc thickness has a crucial impact on the optical depth of the hot illuminated zone. We assume a moderate illumination where the viscous flux equals the X-ray radiation flux. A highly ionized skin is created in the lamp post model, with the outgoing spectrum containing many emission lines and ionization edges in emission or absorption in the soft X-ray domain, as well as an iron line at $\\sim 7 $ keV consisting of a blend of low ionization line from the deepest layers and hydrogen and helium like resonance line from the upper layers, and almost no absorption edge, contrary to the case of a slab of constant density.A full heavy corona completely suppresses the highly ionized zone on the top of the accretion disc and in such case the spectrum is featureless.
Eloranta, Edwin W.
Arctic-Winter Climatology and Radiative Effects of Clouds and Aerosols Based on Lidar and Radar Atmospheric Radiative Transfer (SBDART) code. Results on the climatology and radiative effects of clouds, arctic regions are the site of interactions between aerosols, clouds, radiation and precipitations
Parallel Reacting Flow Calculations for Chemical Vapor Deposition Reactor Design 1
Devine, Karen
, memory, and scalability of distributed memory parallel computers. An unstructured finite element transport from the fluid mechanics and heat transfer. Both works used solution procedures that require the reacting flow model and numerical method and summarize representative calculations using MPSalsa
Proton Transfer in Nucleobases is Mediated by Water Kirill Khistyaev,
Krylov, Anna I.
Proton Transfer in Nucleobases is Mediated by Water Kirill Khistyaev, Amir Golan, Ksenia B. Bravaya, and facilitating efficient proton transport through ion channels and interfaces. This study investigates proton and tunable vacuum ultraviolet synchrotron radiation, we show that water shuts down ionization-induced proton
Resources, framing, and transfer p. 1 Resources, framing, and transfer
Hammer, David
Resources, framing, and transfer p. 1 Resources, framing, and transfer David Hammer Departments. #12;Resources, framing, and transfer p. 2 Resources, framing, and transfer David Hammer, Andrew Elby of activating resources, a language with an explicitly manifold view of cognitive structure. In this chapter, we
Radiation Protection Act (Pennsylvania)
Broader source: Energy.gov [DOE]
This Act combines the radiation safety provisions of The Atomic Energy Development and Radiation Control Act and the Environmental Radiation Protection Act, and empowers the Department of...
HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME
Boyer, Edmond
1 HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME P. H and the sheet metal: This is ventilation by natural convection. The remaining conductive heat from the sheet or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers
The Data Transfer Kit: A geometric rendezvous-based tool for multiphysics data transfer
Slattery, S. R.; Wilson, P. P. H. [Department of Engineering Physics, University of Wisconsin - Madison, 1500 Engineering Dr., Madison, WI 53706 (United States); Pawlowski, R. P. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185 (United States)
2013-07-01T23:59:59.000Z
The Data Transfer Kit (DTK) is a software library designed to provide parallel data transfer services for arbitrary physics components based on the concept of geometric rendezvous. The rendezvous algorithm provides a means to geometrically correlate two geometric domains that may be arbitrarily decomposed in a parallel simulation. By repartitioning both domains such that they have the same geometric domain on each parallel process, efficient and load balanced search operations and data transfer can be performed at a desirable algorithmic time complexity with low communication overhead relative to other types of mapping algorithms. With the increased development efforts in multiphysics simulation and other multiple mesh and geometry problems, generating parallel topology maps for transferring fields and other data between geometric domains is a common operation. The algorithms used to generate parallel topology maps based on the concept of geometric rendezvous as implemented in DTK are described with an example using a conjugate heat transfer calculation and thermal coupling with a neutronics code. In addition, we provide the results of initial scaling studies performed on the Jaguar Cray XK6 system at Oak Ridge National Laboratory for a worse-case-scenario problem in terms of algorithmic complexity that shows good scaling on 0(1 x 104) cores for topology map generation and excellent scaling on 0(1 x 105) cores for the data transfer operation with meshes of O(1 x 109) elements. (authors)
Study of heat transfer in attics with a small scale simulator
Katipamula, Srinivas
1985-01-01T23:59:59.000Z
University Chairman of Advisory Committee: W. D. Turner An experimental study concerned with different modes of heat. transfer in fibrous and cellulose insulating material is presented. A series of experiments was conducted using an attic simulator... to deter- mine the effects of ventilation on attic heat transfer. and the effect of infrared radiation on the thcrn&al conductivity of th& insulation sys- tem and on attic heat transfer. All the tests were perl'ormed at, steady state conditions...
Atmospheric Radiation Measurement Program Science Plan
Ackerman, T
2004-10-31T23:59:59.000Z
The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM's Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.
Heat-transfer coefficients in agitated vessels. Latent heat models
Kumpinsky, E. [Ashland Chemical Co., Columbus, OH (United States)] [Ashland Chemical Co., Columbus, OH (United States)
1996-03-01T23:59:59.000Z
Latent heat models were developed to calculate heat-transfer coefficients in agitated vessels for two cases: (1) heating with a condensable fluid flowing through coils and jackets; (2) vacuum reflux cooling with an overhead condenser. In either case the mathematical treatment, based on macroscopic balances, requires no iterative schemes. In addition to providing heat-transfer coefficients, the models predict flow rates of service fluid through the coils and jackets, estimate the percentage of heat transfer due to latent heat, and compute reflux rates.
A novel nanometric DNA thin film as a sensor for alpha radiation
Cai, Long
of Energy Science, Sungkyunkwan University, Suwon 440746, Korea. The unexpected nuclear accidents have radiation. Due to the high linear energy transfer value, sensors designed to detect such radiation require be one of promising candidates for the development of online radiation sensors. T he Fukushima nuclear
Apparatus and method for detecting gamma radiation
Sigg, R.A.
1994-12-13T23:59:59.000Z
A high efficiency radiation detector is disclosed for measuring X-ray and gamma radiation from small-volume, low-activity liquid samples with an overall uncertainty better than 0.7% (one sigma SD). The radiation detector includes a hyperpure germanium well detector, a collimator, and a reference source. The well detector monitors gamma radiation emitted by the reference source and a radioactive isotope or isotopes in a sample source. The radiation from the reference source is collimated to avoid attenuation of reference source gamma radiation by the sample. Signals from the well detector are processed and stored, and the stored data is analyzed to determine the radioactive isotope(s) content of the sample. Minor self-attenuation corrections are calculated from chemical composition data. 4 figures.
Apparatus and method for detecting gamma radiation
Sigg, Raymond A. (Martinez, GA)
1994-01-01T23:59:59.000Z
A high efficiency radiation detector for measuring X-ray and gamma radiation from small-volume, low-activity liquid samples with an overall uncertainty better than 0.7% (one sigma SD). The radiation detector includes a hyperpure germanium well detector, a collimator, and a reference source. The well detector monitors gamma radiation emitted by the reference source and a radioactive isotope or isotopes in a sample source. The radiation from the reference source is collimated to avoid attenuation of reference source gamma radiation by the sample. Signals from the well detector are processed and stored, and the stored data is analyzed to determine the radioactive isotope(s) content of the sample. Minor self-attenuation corrections are calculated from chemical composition data.
Calibrating the MKAR array using transfer functions
Renwald, M. D. (Marie D.); Taylor, S. R. (Steven R.); Wallace, Terry C.
2003-01-01T23:59:59.000Z
Developing regional discriminants (RDs) at any given seismic station requires a ground-truth database of waveforms from both earthquakes and explosions. Recently installed stations used for seismic monitoring have no single charge explosions on which to base discriminants. We have developed a procedure to map information from surrogate stations, having a long recording history, to newly installed operational stations. We investigated a method to compute transfer functions using known effective 13Ds for a database of earthquakes and explosions located near the Lop Nor nuclear test site and recorded at the KNET array in Kyrgyzstan. For specific source-station paths, transfer functions work well. However, preliminary analysis of India and Pakistan nuclear tests indicate strong azimuthal dependence in the construction of reliable transfer functions. The success of the preliminary work suggests we can apply the same technique to calibrate the recently installed MKAR array using the Global Seismic Network station MAKZ as a surrogate. Both MKAR, an 11-element array operational since 2000, and MAKZ (including its earlier counterpart MAK), operating very broadband instruments since 1994, are located in Eastern Kazakhstan and separated by 25 km. To perform the calibration requires additional considerations not taken into account during the initial investigation: (1) utilizing amplitude spectra, rather than using RDs, to calculate transfer functions; (2) computing transfer functions for a range of azimuths, as we believe the transfer function are azimuthally dependent; and (3) determining whether working with each array element separately or developing a single-input/multiple-output model will provide more stable results and better error estimates.
Journal of Quantitative Spectroscopy & Radiative Transfer 7980 (2003) 11711188
Baum, Bryan A.
.elsevier.com/locate/jqsrt The spectral signature of mixed-phase clouds composed of non-spherical ice crystals and spherical liquid and ice particles may be present. This is typically known as a "mixed-phase" cloud condition the bulk scattering properties of mixed-phase clouds by a linear weighting of the contributions of ice
Journal of Quantitative Spectroscopy & Radiative Transfer 70 (2001) 473504
Baum, Bryan A.
, and the asymmetry parameter of the phase function for ice crystals smaller than 40 m. For particles larger thanÂ13 m spectral region contains a wealth of information that is very useful for the retrieval of ice properties of nonspherical ice crystals that are fundamental to the IR retrieval implementation, we use
Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass
Kitamura, Rei; Pilon, Laurent
2009-01-01T23:59:59.000Z
transport in a machinable glass-ceramic”, Journal of Non-in soda-lime-silicate glasses by reaction with hydrogen”,1971. [16] I. Fanderlik, Glass Science and Technology, Vol.
Monte Carlo radiative heat transfer simulation on a reconfigurable computer
Gokhale, M. (Maya); Ahrens, C. M. (Christine Marie); Frigo, J. (Janette); Minnich, R. G. (Ronald G.); Tripp J. L. (Justin L.)
2004-01-01T23:59:59.000Z
Recently, the appearance of very large (3-10M gate) FPGAs with embedded arithmetic units has opened the door to the possibility of floating point computation on these devices. While previous researchers have described peak performance or kernel matrix operations, there is as yet little experience with mapping an application-specific floating point pipeline onto FPGAs. In this work, we port a supercomputer application benchmark onto Xilinx Virtex II and II Pro FPGAs and compare performance with comparable microprocessor implementation. Our results show that this application-specific pipeline, with 12 multiply, 10 add/subtract, one divide, and two compare modules of single precision floating point data type, shows speedup of 1.6x-1.7x. We analyze the trade-offs between hardware and software 'sweet spots' to characterize the algorithms that will perform well on current and future FPGA architectures.
Journal of Quantitative Spectroscopy & Radiative Transfer 98 (2006) 122129
Zender, Charles
and unaccounted-for solar energy sink in the atmosphere. We spectrally resolve, for the first time, all solar
Journal of Quantitative Spectroscopy & Radiative Transfer 106 (2007) 325347
, aerosol polarimetry sensor; ATSR, along track scanning radiometer; AVHRR, advanced very high resolution radiometer; CALIPSO, cloud-aerosol lidar and infrared pathfinder satellite observations; CLAMS, Chesapeake model; GEWEX, global energy and water cycle experiment; GHG, greenhouse gas; GOME, global ozone
Radiative transfer and thermal performance levels in foam insulation boardstocks
Moreno, John David
1991-01-01T23:59:59.000Z
The validity of predictive models for the thermal conductivity of foam insulation is established based on the fundamental geometry of the closed-cell foam. The extinction coefficient is experimentally and theoretically ...
Journal of Quantitative Spectroscopy & Radiative Transfer 98 (2006) 220237
Pilon, Laurent
2006-01-01T23:59:59.000Z
to the local time and length scales [1]. Of late, with the advent of ultra-short pulsed lasers, this assumption of the order of pico- and femto-seconds. Ultra-short pulsed lasers are used in a wide variety of applications particles from surfaces, optical data storage, optical ablation and ablation of polymers [2]. Ultra-short
Uncertainty of microwave radiative transfer computations in rain
Hong, Sung Wook
2009-06-02T23:59:59.000Z
of the vertical resolution effect on the BT. Secondly, a new temperature profile based on observations was absorbed in the Texas A&M University (TAMU) algorithm. The Precipitation Radar (PR) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI...
Author's personal copy Radiative heat transfer in enhanced hydrogen
Pilon, Laurent
the physical mechanisms responsible for experimental observations that led to the definition of ``photo tube and heated in a furnace or by an incandescent lamp. It was observed that hydrogen release from the glass sample was faster and stronger when heated by an incandescent lamp than within a furnace. Here
Radiative Transfer, Satellite Retrieval Systems and 32 Years
Kuligowski, Bob
computer Â· DEC VAX systems driving Adage image processors #12;NOAA also using Gould SEL computers on the Gould to ingest the Mode AAA data for VAS multispectral imagery Â· I wrote code on the VAX to talk with the Gould and have the Gould extract an image sector from the ingest sector and pass it out to the VAX
Journal of Quantitative Spectroscopy & Radiative Transfer 109 (2008) 10431059
Chance, Kelly
2008-01-01T23:59:59.000Z
Laboratoire Inter-Universitaire des Syste`mes Atmosphe´riques, Faculte´ des Sciences et Technologie, 61 avenue Groupe de Spectrome´trie Mole´culaire et Atmosphe´rique, Universite´ de Reims-Champagne-Ardenne, 51062 91109, USA h Laboratoire de Physique Mole´culaire pour l'Atmosphe`re et l'Astrophysique, Universite
Journal of Quantitative Spectroscopy & Radiative Transfer 100 (2006) 457469
, College Station, TX 77843, USA b Remote sensing Division, Code 7232, Naval Research Laboratory, Washington
EXPERIMENTAL MEASUREMENT OF RADIATION HEAT TRANSFER FROM COMPLEX
ALLAN WILSON Bachelor of Science Oklahoma State University Stillwater, Oklahoma 2005 Submitted Allan, who taught me to set lofty goals and always give my best. And although your lives were not long
Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass
Kitamura, Rei; Pilon, Laurent
2009-01-01T23:59:59.000Z
by a heating lamp emitting in the visible and near infraredwith heating in a furnace at 400 o C. The infrared lamp was
Efficient wireless non-radiative mid-range energy transfer
SoljaÃ¨iÃ¦, Marin
-wire grid was deployed, seri- ous interest and effort was devoted (most notably by Nikola Tesla [1]) towards storage) justifies revisiting investigation of this issue. Today, we face a different challenge than Tesla
Journal of Quantitative Spectroscopy & Radiative Transfer 101 (2006) 404410
of monochromatic light impinging on any point of DS in directions confined to a small solid angle O (called, New York, NY 10025, USA Abstract We revisit the optical theorem relevant to the far-established fact which states that extinction is caused by the interference of the incident and the forward
Influence of Infrared Radiation on Attic Heat Transfer
Katipamula, S.; Turner, W. D.; Murphy, W. E.; O'Neal, D. L.
1985-01-01T23:59:59.000Z
roof temperatures. It was found that a radiant barrier such as aluminum foil can reduce the heat flux significantly. Experimental results were compared to a Three-Region approximate solution developed at Oak Ridge National Laboratories (ORNL). The model...
Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass
Kitamura, Rei; Pilon, Laurent
2009-01-01T23:59:59.000Z
slabs. Moreover, the total heat input during furnace heatingperformed for the same heat input. The optical propertiesheating for the same total heat input. Similarly, Figure 7
Radiation-transparent windows, method for imaging fluid transfers
Shu, Deming (Darien, IL); Wang, Jin (Burr Ridge, IL)
2011-07-26T23:59:59.000Z
A thin, x-ray-transparent window system for environmental chambers involving pneumatic pressures above 40 bar is presented. The window allows for x-ray access to such phenomena as fuel sprays injected into a pressurized chamber that mimics realistic internal combustion engine cylinder operating conditions.
Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 285296
Fan, Tai-Hsi
materials processing applications ranging from metallurgical slag foaming to batch foams in glass melting- cations. One example is glass foams formed on the surface of batch logs of raw materials during the glass the foams formed on the free surface of the molten glass that possess a structure of multiple layers
CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT
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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomassSustainable andBucoda,BurkeNebraska:CDMValenciaLEDSGPDoha -CPFLCPowerISES-
Present and Future Computing Requirements Radiative Transfer of Astrophysical Explosions
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah ProjectPRE-AWARD ACCOUNTINGQuantitativeComputational Cosmology
Improvements to the SHDOM Radiative Transfer Modeling Package
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenITLaboratory in InductivelyImprovements to
A Green's function formalism of energy and momentum transfer in fluctuational electrodynamics
Arvind Narayanaswamy; Yi Zheng
2013-02-03T23:59:59.000Z
Radiative energy and momentum transfer due to fluctuations of electromagnetic fields arising due to temperature difference between objects is described in terms of the cross-spectral densities of the electromagnetic fields. We derive relations between thermal non-equilibrium contributions to energy and momentum transfer and surface integrals of tangential components of the dyadic Green's functions of the vector Helmholtz equation. The expressions derived here are applicable to objects of arbitrary shapes, dielectric functions, as well as magnetic permeabilities. For the case of radiative transfer, we derive expressions for the generalized transmissivity and generalized conductance that are shown to obey reciprocity and agree with theory of black body radiative transfer in the appropriate limit.
Impurity radiation from a tokamak plasma
Morozov, D. Kh.; Baronova, E. O. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation); Senichenkov, I. Yu. [St. Petersburg State Polytechnical University (Russian Federation)
2007-11-15T23:59:59.000Z
In tokamak operating modes, energy balance is often governed by impurity radiation. This is the case near the divertor plates, during impurity pellet injection, during controlled discharge disruptions, etc. The calculation of impurity radiation is a fairly involved task (it is sometimes the most difficult part of the general problem) because the radiation power is determined by the distribution of ions over the excited states and by the rate constants of elementary processes of radiation and absorption. The objective of this paper is to summarize in one place all the approximate formulas that would help investigators to describe radiation from the most often encountered impurities in a fairly simple way in their calculations accounting for plasma radiation, without reference to special literature. Simple approximating formulas describing ionization, recombination, and charge-exchange processes, as well as radiative losses from ions with a given charge, are presented for five impurity species: beryllium, carbon, oxygen, neon, and argon. Estimating formulas that allow one to take into account plasma opacity for resonant photons in line impurity radiation are also presented.
Analysis of radial fin assembly heat transfer with dehumidification
Rosario, L.; Rahman, M.M. [Univ. of South Florida, Tampa, FL (United States). Dept. of Mechanical Engineering
1996-12-31T23:59:59.000Z
The aim of this paper is the analysis of heat transfer in a radial fin assembly during the process of dehumidification. An individual finned tube geometry is a reasonable representation of heat exchangers used in air conditioning. The condensation process involves both heat and mass transfer and the cooling takes place by the removal of sensible as well as latent heat. The ratio of sensible to total heat is an important quantity that defines the heat transfer process during a dehumidifier operation. A one-dimensional model for heat transfer in the fin and the heat exchanger block is developed to study the effects of condensation on the fin surface. The combined heat and mass transfer process is modeled by incorporating the ratio of sensible to total heat in the formulation. The augmentation of heat transfer due to fin was established by comparing heat transfer rate with and without fins under the same operating conditions. Numerical calculations were carried out to study the effects of relative humidity and dry bulb temperature of the incoming air, and cold fluid temperature inside the coil on the performance of the heat exchanger. Results were compared to those published for rectangular fin under humid condition showed excellent agreement when the present model was used to compute that limiting condition. It was found that the heat transfer rate increased with increment in both dry bulb temperature and relative humidity of the air. The augmentation factor, however, decreased with increment in relative humidity and the dry bulb temperature.
Goddard III, William A.
hole mobility. Electronic band structure calculations have previously been used to predict charge the reorganization energy and electron-transfer coupling matrix elements and molecular dynamics (MD) to do Calculations Wei-Qiao Deng and William A. Goddard III* Materials and Process Simulation Center, California
Application of Improved Radiation Modeling to General Circulation Models
Michael J Iacono
2011-04-07T23:59:59.000Z
This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.
Urban Sewage Delivery Heat Transfer System (2): Heat Transfer
Zhang, C.; Wu, R.; Li, X.; Li, G.; Zhuang, Z.; Sun, D.
2006-01-01T23:59:59.000Z
The thimble delivery heat-transfer (TDHT) system is one of the primary modes to utilize the energy of urban sewage. Using the efficiency-number of transfer units method ( ), the heat-transfer efficiencies of the parallel-flow and reverse-flow TDTH...
Urban Sewage Delivery Heat Transfer System (2): Heat Transfer
Zhang, C.; Wu, R.; Li, X.; Li, G.; Zhuang, Z.; Sun, D.
2006-01-01T23:59:59.000Z
The thimble delivery heat-transfer (TDHT) system is one of the primary modes to utilize the energy of urban sewage. Using the efficiency-number of transfer units method ( ), the heat-transfer efficiencies of the parallel-flow and reverse-flow TDTH...
FileName//FileDate//PNNL-SA-##### DPA Calculational Methodologies Used in Fission
McDonald, Kirk
FileName//FileDate//PNNL-SA-##### DPA Calculational Methodologies Used in Fission and Fusion Reactor Materials Applications David Wootan - david.wootan@pnnl.gov, 1-509-372-6865 Radiation Damage
Radiative acceleration and transient, radiation-induced electric fields
L. Zampieri; R. Turolla; L. Foschini; A. Treves
2003-04-14T23:59:59.000Z
The radiative acceleration of particles and the electrostatic potential fields that arise in low density plasmas hit by radiation produced by a transient, compact source are investigated. We calculate the dynamical evolution and asymptotic energy of the charged particles accelerated by the photons and the radiation-induced electric double layer in the full relativistic, Klein-Nishina regime. For fluxes in excess of $10^{27}$ ${\\rm erg} {\\rm cm}^{-2} {\\rm s}^{-1}$, the radiative force on a diluted plasma ($n\\la 10^{11}$ cm$^{-3}$) is so strong that electrons are accelerated rapidly to relativistic speeds while ions lag behind owing to their larger inertia. The ions are later effectively accelerated by the strong radiation-induced double layer electric field up to Lorentz factors $\\approx 100$, attainable in the case of negligible Compton drag. The asymptotic energies achieved by both ions and electrons are larger by a factor 2--4 with respect to what one could naively expect assuming that the electron-ion assembly is a rigidly coupled system. The regime we investigate may be relevant within the framework of giant flares from soft gamma-repeaters.
Physics of intense, high energy radiation effects.
Hjalmarson, Harold Paul; Hartman, E. Frederick; Magyar, Rudolph J.; Crozier, Paul Stewart
2011-02-01T23:59:59.000Z
This document summarizes the work done in our three-year LDRD project titled 'Physics of Intense, High Energy Radiation Effects.' This LDRD is focused on electrical effects of ionizing radiation at high dose-rates. One major thrust throughout the project has been the radiation-induced conductivity (RIC) produced by the ionizing radiation. Another important consideration has been the electrical effect of dose-enhanced radiation. This transient effect can produce an electromagnetic pulse (EMP). The unifying theme of the project has been the dielectric function. This quantity contains much of the physics covered in this project. For example, the work on transient electrical effects in radiation-induced conductivity (RIC) has been a key focus for the work on the EMP effects. This physics in contained in the dielectric function, which can also be expressed as a conductivity. The transient defects created during a radiation event are also contained, in principle. The energy loss lead the hot electrons and holes is given by the stopping power of ionizing radiation. This information is given by the inverse dielectric function. Finally, the short time atomistic phenomena caused by ionizing radiation can also be considered to be contained within the dielectric function. During the LDRD, meetings about the work were held every week. These discussions involved theorists, experimentalists and engineers. These discussions branched out into the work done in other projects. For example, the work on EMP effects had influence on another project focused on such phenomena in gases. Furthermore, the physics of radiation detectors and radiation dosimeters was often discussed, and these discussions had impact on related projects. Some LDRD-related documents are now stored on a sharepoint site (https://sharepoint.sandia.gov/sites/LDRD-REMS/default.aspx). In the remainder of this document the work is described in catergories but there is much overlap between the atomistic calculations, the continuum calculations and the experiments.
Faculty Positions Heat Transfer and
Faculty Positions Heat Transfer and Thermal/Energy Sciences Naval Postgraduate School Monterey-track faculty position at the assistant professor level in the areas of Heat Transfer and Thermal/Fluid Sciences
Spallation Neutron Source Radiation Shielding Issues
Azmy, Y.Y.; Barnes, J.M.; Drischler, J.D.; Johnston, J.O.; Lillie, R.A.; McNeilly, G.S.; Santoro, R.T.
1999-11-14T23:59:59.000Z
This paper summarizes results of Spallation Neutron Source calculations to estimate radiation hazards and shielding requirements for activated Mercury, target components, target cooling water, and {sup 7}Be plateout. Dose rates in the accelerator tunnel from activation of magnets and concrete were investigated. The impact of gaps and other streaming paths on the radiation environment inside the test cell during operation and after shutdown were also assessed.
Radiation detector system having heat pipe based cooling
Iwanczyk, Jan S.; Saveliev, Valeri D.; Barkan, Shaul
2006-10-31T23:59:59.000Z
A radiation detector system having a heat pipe based cooling. The radiation detector system includes a radiation detector thermally coupled to a thermo electric cooler (TEC). The TEC cools down the radiation detector, whereby heat is generated by the TEC. A heat removal device dissipates the heat generated by the TEC to surrounding environment. A heat pipe has a first end thermally coupled to the TEC to receive the heat generated by the TEC, and a second end thermally coupled to the heat removal device. The heat pipe transfers the heat generated by the TEC from the first end to the second end to be removed by the heat removal device.
V. Suleimanov; K. Werner
2007-02-15T23:59:59.000Z
Emergent model spectra of neutron star atmospheres are widely used to fit the observed soft X-ray spectra of different types of isolated neutron stars. We investigate the effect of Compton scattering on the emergent spectra of hot (T_eff > 10^6 K) isolated neutron stars with weak magnetic fields. In order to compute model atmospheres in hydrostatic and radiative equilibrium we solve the radiation transfer equation with the Kompaneets operator. We calculate a set of models with effective temperatures in the range 1 - 5 * 10^6 K, with two values of surface gravity (log g = 13.9 and 14.3) and different chemical compositions. Radiation spectra computed with Compton scattering are softer than those computed without Compton scattering at high energies (E > 5 keV) for light elements (H or He) model atmospheres. The Compton effect is more significant in H model atmospheres and models with low surface gravity. The emergent spectra of the hottest (T_eff > 3 * 10^6 K) model atmospheres can be described by diluted blackbody spectra with hardness factors ~ 1.6 - 1.9. Compton scattering is less important in models with solar abundance of heavy elements.
QER- Comment of Energy Transfer
Broader source: Energy.gov [DOE]
From: Lee Hanse Executive Vice President Interstate Energy Transfer Mobile - 210 464 2929 Office - 210 403 6455
CALCULATING INTERIOR DAYLIGHT ILLUMINATION WITH A PROGRAMMABLE HAND CALCULATOR
Bryan, Harvey J.
2013-01-01T23:59:59.000Z
Committee E-3.2, "Daylight: International RecommendationsCalculation of Natural Daylight," CIE PUBLICATION No. 16,Committee E-3.2, "Natural Daylight: Official Recommenda-
CALCULATING INTERIOR DAYLIGHT ILLUMINATION WITH A PROGRAMMABLE HAND CALCULATOR
Bryan, Harvey J.
2013-01-01T23:59:59.000Z
Committee E-3.2, "Daylight: International Recommendationsthe Calculation of Natural Daylight, 11 CIE PUBLICATION No.Committee E-3.2 1 "Natural Daylight: Official Recommenda-
Adaptors for radiation detectors
Livesay, Ronald Jason
2014-04-22T23:59:59.000Z
Described herein are adaptors and other devices for radiation detectors that can be used to make accurate spectral measurements of both small and large bulk sources of radioactivity, such as building structures, soils, vessels, large equipment, and liquid bodies. Some exemplary devices comprise an adaptor for a radiation detector, wherein the adaptor can be configured to collimate radiation passing through the adapter from an external radiation source to the radiation detector and the adaptor can be configured to enclose a radiation source within the adapter to allow the radiation detector to measure radiation emitted from the enclosed radiation source.
Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)
1992-01-01T23:59:59.000Z
Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.
Plastic container bagless transfer
Tibrea, Steven L.; D'Amelio, Joseph A.; Daugherty, Brent A.
2003-11-18T23:59:59.000Z
A process and apparatus are provided for transferring material from an isolated environment into a storage carrier through a conduit that can be sealed with a plug. The plug and conduit can then be severed to provide a hermetically sealed storage carrier containing the material which may be transported for storage or disposal and to maintain a seal between the isolated environment and the ambient environment.
Mass transfer andMass transfer and Mass transfer andMass transfer and
Zevenhoven, Ron
't be determined A correlation for Sherwood number (Sh) based on di i l l i b d l i Sh diff idimensional analysis for mass transfer with convection: I l f d fl d b (l b l ) Internal forced flow: inside a tube (laminar A in fluid medium B in a flow with characteristic velocity and size characteristic d: kA = f(d, w, (= fluid
CANISTER HANDLING FACILITY CRITICALITY SAFETY CALCULATIONS
C.E. Sanders
2005-04-07T23:59:59.000Z
This design calculation revises and updates the previous criticality evaluation for the canister handling, transfer and staging operations to be performed in the Canister Handling Facility (CHF) documented in BSC [Bechtel SAIC Company] 2004 [DIRS 167614]. The purpose of the calculation is to demonstrate that the handling operations of canisters performed in the CHF meet the nuclear criticality safety design criteria specified in the ''Project Design Criteria (PDC) Document'' (BSC 2004 [DIRS 171599], Section 4.9.2.2), the nuclear facility safety requirement in ''Project Requirements Document'' (Canori and Leitner 2003 [DIRS 166275], p. 4-206), the functional/operational nuclear safety requirement in the ''Project Functional and Operational Requirements'' document (Curry 2004 [DIRS 170557], p. 75), and the functional nuclear criticality safety requirements described in the ''Canister Handling Facility Description Document'' (BSC 2004 [DIRS 168992], Sections 3.1.1.3.4.13 and 3.2.3). Specific scope of work contained in this activity consists of updating the Category 1 and 2 event sequence evaluations as identified in the ''Categorization of Event Sequences for License Application'' (BSC 2004 [DIRS 167268], Section 7). The CHF is limited in throughput capacity to handling sealed U.S. Department of Energy (DOE) spent nuclear fuel (SNF) and high-level radioactive waste (HLW) canisters, defense high-level radioactive waste (DHLW), naval canisters, multicanister overpacks (MCOs), vertical dual-purpose canisters (DPCs), and multipurpose canisters (MPCs) (if and when they become available) (BSC 2004 [DIRS 168992], p. 1-1). It should be noted that the design and safety analyses of the naval canisters are the responsibility of the U.S. Department of the Navy (Naval Nuclear Propulsion Program) and will not be included in this document. In addition, this calculation is valid for the current design of the CHF and may not reflect the ongoing design evolution of the facility. However, it is anticipated that design changes to the facility layout will have little or no impact on the criticality results and/or conclusions presented in this document. This calculation is subject to the ''Quality Assurance Requirements and Description'' (DOE 2004 [DIRS 171539]) because the CHF is included in the Q-List (BSC 2005 [DIRS 171190], p. A-3) as an item important to safety. This calculation is prepared in accordance with AP-3.12Q, ''Design Calculations and Analyses'' [DIRS 168413].
Kurnikova, Maria
calculations of electronic couplings, molecular dynamics simulations of molecular geometries, and Poisson exists to interpret electron-transfer (ET) reactions and their dependence upon molecular structure.1Structural Fluctuations, Spin, Reorganization Energy, and Tunneling Energy Control
Methods for transfer matrix evaluation applied to thermoacoustics
Paris-Sud XI, Université de
Methods for transfer matrix evaluation applied to thermoacoustics F. Bannwart, G. Penelet, P 2012 Nantes Conference 23-27 April 2012, Nantes, France 3029 #12;The design of a thermoacoustic (TA the required thermoacoustic instability in its core to make it work. Such conditions can be calculated
A vectorized heat transfer model for solid reactor cores
Rider, W.J.; Cappiello, M.W.; Liles, D.R.
1990-01-01T23:59:59.000Z
The new generation of nuclear reactors includes designs that are significantly different from light water reactors. Among these new reactor designs is the Modular High-Temperature Gas-Cooled Reactor (MHTGR). In addition, nuclear thermal rockets share a number of similarities with terrestrial HTGRs and would be amenable to similar types of analyses. In these reactors, the heat transfer in the solid core mass is of primary interest in design and safety assessment. One significant safety feature of these reactors is the capability to withstand a loss of pressure and forced cooling in the primary system and still maintain peak fuel temperatures below the safe threshold for retaining the fission products. To accurately assess the performance of gas-cooled reactors during these types of transients, a Helium/Hydrogen Cooled Reactor Analysis (HERA) computer code has been developed. HERA has the ability to model arbitrary geometries in three dimensions, which allows the user to easily analyze reactor cores constructed of prismatic graphite elements. The code accounts for heat generation in the fuel, control rods and other structures; conduction and radiation across gaps; convection to the coolant; and a variety of boundary conditions. The numerical solution scheme has been optimized for vector computers, making long transient analyses economical. Time integration is either explicit or implicit, which allows the use of the model to accurately calculate both short- or long-term transients with an efficient use of computer time. Both the basic spatial and temporal integration schemes have been benchmarked against analytical solutions. Also, HERA has been used to analyze a depressurized loss of forced cooling transient in a HTGR with a very detailed three-dimensional input model. The results compare favorably with other means of analysis and provide further validation of the models and methods. 18 refs., 11 figs.
Effect of surface conditions on boiling heat transfer of refrigerants in shell-and-tube evaporators
Danilova, G.N.; Dyundin, V.A.; Borishanskaya, A.V.; Soloviyov, A.G.; Vol'nykh, Y.A.; Kozyrev, A.A.
1990-01-01T23:59:59.000Z
Experimental results are presented for the boiling heat transfer performance of R 22 and R 717 on surfaces with porous metallized coatings. A calculational-theoretical model is given for predicting the heat transfer of refrigerants boiling on a bundle of finned tubes.
Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland
Graaf, Martin de
Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland M. de Graaf #12;Heat transfer in katabatic flow Measurements on the Morteratsch glacier, Switzerland Martin de is used to calculate surface heat fluxes over glaciers. As determination of surface fluxes still
A unified radiative magnetohydrodynamics code for lightning-like discharge simulations
Chen, Qiang, E-mail: cq0405@126.com; Chen, Bin, E-mail: emcchen@163.com; Xiong, Run; Cai, Zhaoyang [National Key Laboratory of Electromagnetic Environment and Electro-optical Engineering, PLA University of Science and Technology, Nanjing 210007 (China)] [National Key Laboratory of Electromagnetic Environment and Electro-optical Engineering, PLA University of Science and Technology, Nanjing 210007 (China); Chen, P. F., E-mail: chenpf@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)
2014-03-15T23:59:59.000Z
A two-dimensional Eulerian finite difference code is developed for solving the non-ideal magnetohydrodynamic (MHD) equations including the effects of self-consistent magnetic field, thermal conduction, resistivity, gravity, and radiation transfer, which when combined with specified pulse current models and plasma equations of state, can be used as a unified lightning return stroke solver. The differential equations are written in the covariant form in the cylindrical geometry and kept in the conservative form which enables some high-accuracy shock capturing schemes to be equipped in the lightning channel configuration naturally. In this code, the 5-order weighted essentially non-oscillatory scheme combined with Lax-Friedrichs flux splitting method is introduced for computing the convection terms of the MHD equations. The 3-order total variation diminishing Runge-Kutta integral operator is also equipped to keep the time-space accuracy of consistency. The numerical algorithms for non-ideal terms, e.g., artificial viscosity, resistivity, and thermal conduction, are introduced in the code via operator splitting method. This code assumes the radiation is in local thermodynamic equilibrium with plasma components and the flux limited diffusion algorithm with grey opacities is implemented for computing the radiation transfer. The transport coefficients and equation of state in this code are obtained from detailed particle population distribution calculation, which makes the numerical model is self-consistent. This code is systematically validated via the Sedov blast solutions and then used for lightning return stroke simulations with the peak current being 20?kA, 30?kA, and 40?kA, respectively. The results show that this numerical model consistent with observations and previous numerical results. The population distribution evolution and energy conservation problems are also discussed.
Nogueira, Liebert Parreiras; Braz, Delson [Nuclear Instrumentation Laboratory / COPPE / UFRJ, P.O. Box 68509, 21945-970, Rio de Janeiro (Brazil); Barroso, Regina Cely [Physics Institute / State University of Rio de Janeiro, 20550-900, Rio de Janeiro (Brazil); Almeida, Carlos Eduardo de; Andrade, Cherley Borba [Laboratory of Radiological Sciences / State University of Rio de Janeiro, Rio de Janeiro (Brazil); Tromba, Giuliana [Sincrotrone Trieste SCpA, Strada Statale S.S. 14 km 163.5, 34012 Basovizza, Trieste (Italy)
2011-12-13T23:59:59.000Z
In this work, we investigated the consequences of irradiation in the femora and ribs of rats submitted to radiation doses of 5 Gy. Three different sites in femur specimens (head, distal metaphysis and distal epiphysis) and one in ribs (ventral) were imaged using synchrotron radiation microcomputed tomography to assess trabecular bone microarchitecture. Histomorphometric quantification was calculated directly from the 3D microtomographic images using synchrotron radiation. The 3D microtomographic images were obtained at the SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at the Elettra Synchrotron Laboratory in Trieste, Italy. A better understanding of the biological interactions that occur after exposure to photon radiation is needed in order to optimize therapeutic regimens and facilitate development and strategies that decrease radiation-induced side effects in humans. Results showed significant differences between irradiated and non-irradiated specimens, mostly in head and distal metaphysis bone sites.
Methods of calculating the post-closure performance of high-level waste repositories
Ross, B. (ed.)
1989-02-01T23:59:59.000Z
This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs.
Linear Momentum and Angular-Momentum Transfer in the Reactions of O-16 with Sm-154
Namboodiri, M. N.; Choudhury, R. K.; Alder, L.; Bronson, J. D.; Fabris, D.; Garg, U.; Gonthier, P. L.; Hagel, K.; Haenni, DR; Lui, YW; Majka, Z.; Mouchaty, G.; Murakami, T.; Natowitz, J. B.; Nebbia, G.; Schmitt, R. P.; Simon, S.; Sullivan, J. P.; Youngblood, David H.
1987-01-01T23:59:59.000Z
calculated correspond roughly to the condition of vanishing pockets in the nuclear+ Coulomb + centrifugal potential. In this model there is no fric- tional force which would allow higher partial waves to be damped and contribute to complete fusion... to the differences in the evaluation of the Coulomb potential, although the distance at which the transfer takes place is calculated to be the same in both versions. Reference 10 addresses the question of angular momen- tum transfer explicitly, while Ref. 11...
environmental management radiation protection
Entekhabi, Dara
EHS environmental management biosafety radiation protection industrial hygiene safety Working: Biosafety, Environmental Management, Industrial Hygiene, Radiation Protection and Safety. Each specialized Management Program, Industrial Hygiene, Radiation Protection Program, and the Safety Program. (http
DETECTORS FOR RADIATION DOSIMETRY
Perez-Mendez, V.
2010-01-01T23:59:59.000Z
J. Price, "Nuclear Radiation Detection" (2nd ed. , New York:4) G. F. Knoll, "Radiation Detection and Measurement" (NewSons, Inc. from "Radiation Detection and Measurement," G. F.
Courses on Synchrotron Radiation
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Synchrotron Radiation The following is an incomplete list of courses on Synchrotron Radiation. For additional courses, check lightsources.org. XAFS School The APS XAFS School...
Solar radiation resource assessment
Not Available
1990-11-01T23:59:59.000Z
The bulletin discusses the following: introduction; Why is solar radiation resource assessment important Understanding the basics; the solar radiation resource assessment project; and future activities.
Broader source: Energy.gov [DOE]
The Department of Health is responsible for regulating radiation and radioactive materials in the Commonwealth of Virginia. Although the Department's Radiation Control Program primarily focuses on...
None
2013-11-19T23:59:59.000Z
Wireless Power Transfer is an innovative approach using magnetic resonance coupling of air core transformers designed for today's growing plug-in electric vehicle market. This technology can provide a convenient, safe and flexible means to charge electric vehicles under stationary and dynamic conditions. Plug-in Electric Vehicles (PEV) are burdened by the need for cable and plug charger, galvanic isolation of the on-board electronics, bulk and cost of this charger and the large energy storage system (ESS) packs needed. With a system where you have to physically plug in there are a number of occasions where the owner could very well forget to charge the vehicle. For stationary applications (like charging of a PHEV at home), ORNL's innovative wireless power transfer technology adds a convenience factor compared to actually plugging in which will mean that the vehicle will have a full charge every morning. Electric vehicle charging must be safe, compact and efficient in order to be convenient for customers. By reconfiguring the transformer and altering the resonance frequency, energy is transferred to the battery with lower energy losses and with fewer demands on the primary circuit by the rest of the transformer system. The ORNL discovery shows that sufficient power for the battery can be transferred from the primary to secondary circuits without significant energy losses if the operating frequency is set at 50% to 95% of the resonance frequency of the circuit. The electrical power is then transmitted to the chargeable battery, which is electrically coupled to the secondary circuit through the air core transformer. Some advantages include: Reduced energy losses during transfer of energy to the battery; A charge potential that is relatively unaffected by up to 25% misalignment of vehicle; and Other receiving components draw less power from the primary circuit. These advantages allow wireless power technology applications to expand at the workplace and beyond as the demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the energy for the transportation sector and reduce greatly petroleum consump
None
2013-07-22T23:59:59.000Z
Wireless Power Transfer is an innovative approach using magnetic resonance coupling of air core transformers designed for today's growing plug-in electric vehicle market. This technology can provide a convenient, safe and flexible means to charge electric vehicles under stationary and dynamic conditions. Plug-in Electric Vehicles (PEV) are burdened by the need for cable and plug charger, galvanic isolation of the on-board electronics, bulk and cost of this charger and the large energy storage system (ESS) packs needed. With a system where you have to physically plug in there are a number of occasions where the owner could very well forget to charge the vehicle. For stationary applications (like charging of a PHEV at home), ORNL's innovative wireless power transfer technology adds a convenience factor compared to actually plugging in which will mean that the vehicle will have a full charge every morning. Electric vehicle charging must be safe, compact and efficient in order to be convenient for customers. By reconfiguring the transformer and altering the resonance frequency, energy is transferred to the battery with lower energy losses and with fewer demands on the primary circuit by the rest of the transformer system. The ORNL discovery shows that sufficient power for the battery can be transferred from the primary to secondary circuits without significant energy losses if the operating frequency is set at 50% to 95% of the resonance frequency of the circuit. The electrical power is then transmitted to the chargeable battery, which is electrically coupled to the secondary circuit through the air core transformer. Some advantages include: Reduced energy losses during transfer of energy to the battery; A charge potential that is relatively unaffected by up to 25% misalignment of vehicle; and Other receiving components draw less power from the primary circuit. These advantages allow wireless power technology applications to expand at the workplace and beyond as the demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the energy for the transportation sector and reduce greatly petroleum consump
Fourier analysis of conductive heat transfer for glazed roofing materials
Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah [Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Zakaria, Nor Zaini [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)
2014-07-10T23:59:59.000Z
For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.
Computational Tools for Supersymmetry Calculations
Howard Baer
2009-12-16T23:59:59.000Z
I present a brief overview of a variety of computational tools for supersymmetry calculations, including: spectrum generators, cross section and branching fraction calculators, low energy constraints, general purpose event generators, matrix element event generators, SUSY dark matter codes, parameter extraction codes and Les Houches interface tools.
Manipulator mounted transfer platform
Dobbins, James C. (Idaho Falls, ID); Hoover, Mark A. (Idaho Falls, ID); May, Kay W. (Idaho Falls, ID); Ross, Maurice J. (Pocatello, ID)
1990-01-01T23:59:59.000Z
A transfer platform for the conveyance of objects by a manipulator includes a bed frame and saddle clamp secured along an edge of the bed frame and adapted so as to secure the bed frame to a horizontal crosspiece of the manipulator. The platform may thus move with the manipulator in a reciprocal linear path defined by a guide rail. A bed insert may be provided for the support of conveyed objects and a lifting bail may be provided to permit the manipulator arm to install the bed frame upon the crosspiece under remote control.
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Technology Transfer Reporting Form
Office of Environmental Management (EM)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently AskedEnergyIssuesEnergy Solar Decathlon |1999Energy-Technology TransferThis
Distribution of particles which produces a desired radiation pattern
A. G. Ramm
2005-07-01T23:59:59.000Z
A method is given for calculation of a distribution of small particles, embedded in a medium, so that the resulting medium would have a desired radiation pattern for the plane wave scattering by this medium.
Muon transfer from hydrogen to helium
Bystritskii, V.M.; Dzhelepov, V.P.; Petrukhin, V.I.; Rudenko, A.I.; Suvorov, V.M.; Filchenkov, V.V.; Khovanskii, N.N.; Khomenko, B.A.
1983-04-01T23:59:59.000Z
It is found that ..mu../sup -/ mesons stopped in a gas mixture of hydrogen, helium, and xenon (hydrogen pressure about 20 atmospheres, helium and xenon densities relative to hydrogen 0.05--2 and approx.10/sup -4/ respectively) are transferred from the p..mu.. atoms in the ground state to helium atoms at a rate lambda/sub He/ = (3.6 +- 1.0)x10/sup 8/ sec/sup -1/. The result is in good agreement with the calculations in which a novel mesic-molecular mechanism of p..mu..-atom charge exchange with helium nuclei is taken into account. The dependence of the probability for p..mu..-atom formation in the ground state on the helium density is measured. An analysis of this dependence and a comparison of it with the corresponding data for ..pi../sup -/ mesons indicate that muons can also be transferred from excited levels of p..mu.. atoms at a rate higher than in the case of p..pi.. atoms (transfer constant ..lambda../sub ..mu../ = 3.8 +- 0.3 compared with ..lambda../sub ..pi../ = 1.84 +- 0.09).
Study of cloud properties from single-scattering, radiative forcing, and retrieval perspectives
Lee, Yong-Keun
2009-06-02T23:59:59.000Z
This dissertation reports on three different yet related topics in light scattering computation, radiative transfer simulation, and remote sensing implementation, regarding the cloud properties and the retrieval of cloud properties from satellite...
A 2-D Test Problem for CFD Modeling Heat Transfer in Spent Fuel Transfer Cask Neutron Shields
Zigh, Ghani; Solis, Jorge; Fort, James A.
2011-01-14T23:59:59.000Z
In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 5-10 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper presents results for a simple 2-D problem that is an effective numerical analog for the neutron shield application. Because it is 2-D, solutions can be obtained relatively quickly allowing a comparison and assessment of sensitivity to model parameter changes. Turbulence models are considered as well as the tradeoff between steady state and transient solutions. Solutions are compared for two commercial CFD codes, FLUENT and STAR-CCM+. The results can be used to provide input to the CFD Best Practices for this application. Following study results for the 2-D test problem, a comparison of simulation results is provided for a high Rayleigh number experiment with large annular gap. Because the geometry of this validation is significantly different from the neutron shield, and due to the critical nature of this application, the argument is made for new experiments at representative scales
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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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z C o . C l a r8.0
Huang, Feifei; Liu, Xueqiang [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Hu, Lili; Chen, Danping, E-mail: dpchen2008@aliyun.com [Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)
2014-07-21T23:59:59.000Z
This paper investigates 2.0??m emission properties and energy transfer processes in the Er{sup 3+}/Ho{sup 3+} codoped fluorotellurite glass. The measured absorption spectra demonstrate that the codoped sample can be pumped by 1550?nm excitation efficiently. Judd-Ofelt and radiative parameters are calculated and discussed. Intensive 2.0??m emission originating from Ho{sup 3+}: {sup 5}I{sub 7}?{sup 5}I{sub 8} transition is observed and a long lifetime (11?ms) of the {sup 5}I{sub 7} level is measured when Ho{sup 3+} ions are sensitized by Er{sup 3+} ions. Meanwhile, the upconversion spectra of the Er{sup 3+} singly and codoped samples are obtained and the energy transfer processes of the two ions is discussed based on the change of the upconversion emissions. The microscopic interaction parameters of the phonon-assisted (Er{sup 3+}: {sup 4}I{sub 13/2}?Ho{sup 3+}:{sup 5}I{sub 7}) process are calculated and the microparameter reaches as high as 10.1?×?10{sup ?41} cm{sup 6}/s. Hence, these results indicate that this Ho{sup 3+}/Er{sup 3+} codoped fluorotellurite glass will be a suitable material for developing solid state laser around 2.0??m.
An electronic radiation of blackbody: Cosmic electron background
Jian-Miin Liu
2008-02-23T23:59:59.000Z
The Universe owns the electronic radiation of blackbody at temperature 2.725 K, which we call the cosmic electron background. We calculate its radiation spectrum. The energy distribution of number density of electrons in the cosmic electron background becomes zero as energy goes to both zero and infinity. It has one maximum peak near the energy level of 10**(-23) J.
Production and Transfer of Energy and Information in Hamiltonian Systems
Ch. G. Antonopoulos; E. Bianco-Martinez; M. S. Baptista
2014-01-23T23:59:59.000Z
We present novel results that relate energy and information transfer with sensitivity to initial conditions in chaotic multi-dimensional Hamiltonian systems. We show the relation among Kolmogorov-Sinai entropy, Lyapunov exponents, and upper bounds for the Mutual Information Rate calculated in the Hamiltonian phase space and on bi-dimensional subspaces. Our main result is that the net amount of transfer from kinetic to potential energy per unit of time is a power-law of the upper bound for the Mutual Information Rate between kinetic and potential energies, and also a power-law of the Kolmogorov-Sinai entropy. Therefore, transfer of energy is related with both transfer and production of information. However, the power-law nature of this relation means that a small increment of energy transferred leads to a relatively much larger increase of the information exchanged. Then, we propose an ``experimental'' implementation of a 1-dimensional communication channel based on a Hamiltonian system, and calculate the actual rate with which information is exchanged between the first and last particle of the channel. Finally, a relation between our results and important quantities of thermodynamics is presented.
SB EE Calculator | Argonne National Laboratory
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Calculator Energy Efficiency Decision Support Calculator Argonne's Energy Efficiency Decision Support Calculator is a simple tool that small business owners can use to quickly...
GENII. Environmental Radiation Dosimetry Suite
Napier, B.A. [Pacific Northwest Lab., Richland, WA, (United States)
1988-12-01T23:59:59.000Z
GENII was developed to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) into the environmental pathway analysis models used at Hanford. GENII is a coupled system of seven programs and the associated data libraries that comprise the Hanford Dosimetry System (Generation II) to estimate potential radiation doses to individuals or populations from both routine and accidental releases of radionuclides to air or water and residual contamination from spills or decontamination operations. The GENII system includes interactive menu-driven programs to assist the user with scenario generation and data input,internal and external dose factor generators, and environmental dosimetry programs. The programs analyze environmental contamination resulting from both far-field and near-field scenarios. A far-field scenario focuses outward from a source, while a near-field scenario focuses in toward a receptor. GENII can calculate annual dose, committed dose, and accumulated dose from acute and chronic releases from ground or elevated sources to air or water and from initial contamination of soil or surfaces and can evaluate exposure pathways including direct exposure via water, soil, air, inhalation pathways, and ingestion pathways. In addition, GENII can perform 10,000 years migration analyses and can be used for retrospective calculations of potential radiation doses resulting from routine emissions and for prospective dose calculations for purposes such as siting facilities, environmental impact statements, and safety analysis reports.
Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.
1992-03-01T23:59:59.000Z
The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth`s atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy`s Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described.
Self-force approach for radiation reaction
Lior M. Burko
1999-12-13T23:59:59.000Z
We overview the recently proposed mode-sum regularization prescription (MSRP) for the calculation of the local radiation-reaction forces, which are crucial for the orbital evolution of binaries. We then describe some new results which were obtained using MSRP, and discuss their importance for gravitational-wave astronomy.
Absorption of solar radiation by solar neutrinos
G. Duplancic; P. Minkowski; J. Trampetic
2004-03-22T23:59:59.000Z
We calculate the absorption probability of photons radiated from the surface of the Sun by a left-handed neutrino with definite mass and a typical momentum for which we choose |p_1|=0.2 MeV, producing a heavier right-handed antineutrino. Considering two transitions the \
Charmonium meson and hybrid radiative transitions
Guo, Peng [Indiana U., JLAB; Yépez-Martínez, Tochtli [Indiana U.; Szczepaniak, Adam P. [Indiana U., JLAB
2014-06-01T23:59:59.000Z
We consider the non-relativistic limit of the QCD Hamiltonian in the Coulomb gauge, to describe radiative transitions between conventional charmonium states and from the lowest multiplet of cc¯ hybrids to charmonium mesons. The results are compared to potential quark models and lattices calculations.
Why does gravitational radiation produce vorticity?
L. Herrera; W. Barreto; J. Carot; A. Di Prisco
2007-03-26T23:59:59.000Z
We calculate the vorticity of world--lines of observers at rest in a Bondi--Sachs frame, produced by gravitational radiation, in a general Sachs metric. We claim that such an effect is related to the super--Poynting vector, in a similar way as the existence of the electromagnetic Poynting vector is related to the vorticity in stationary electrovacum spacetimes.
Technology transfer | Argonne National Laboratory
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Technology transfer Technology Development and Commercialization at Argonne Read more about Technology Development and Commercialization at Argonne New Director to lead Technology...
QED radiative corrections to virtual Compton scattering
M. Vanderhaeghen; J. M. Friedrich; D. Lhuillier; D. Marchand; L. Van Hoorebeke; J. Van de Wiele
2000-01-12T23:59:59.000Z
The QED radiative corrections to virtual Compton scattering (reaction $e p \\to e p \\gamma$) are calculated to first order in $\\alpha_{em} \\equiv e^2 / 4 \\pi$. A detailed study is presented for the one-loop virtual corrections and for the first order soft-photon emission contributions. Furthermore, a full numerical calculation is given for the radiative tail, corresponding with photon emission processes, where the photon energy is not very small compared with the lepton momenta. We compare our results with existing works on elastic electron-proton scattering, and show for the $e p \\to e p \\gamma$ reaction how the observables are modified due to these first order QED radiative corrections. We show results for both unpolarized and polarized observables of the virtual Compton scattering in the low energy region (where one is sensitive to the generalized polarizabilities of the nucleon), as well as for the deeply virtual Compton scattering.
Calculation of Neutral Beam Injection into SSPX
Pearlstein, L D; Casper, T A; Hill, D N; LoDestro, L L; McLean, H S
2006-06-13T23:59:59.000Z
The SSPX spheromak experiment has achieved electron temperatures of 350eV and confinement consistent with closed magnetic surfaces. In addition, there is evidence that the experiment may be up against an operational beta limit for Ohmic heating. To test this barrier, there are firm plans to add two 0.9MW Neutral Beam (NB) sources to the experiment. A question is whether the limit is due to instability. Since the deposited Ohmic power in the core is relatively small the additional power from the beams is sufficient to significantly increase the electron temperature. Here we present results of computations that will support this contention. We have developed a new NB module to calculate the orbits of the injected fast fast-ions. The previous computation made heavy use of tokamak ordering which fails for a tight-aspect-ratio device, where B{sub tor} {approx} B{sub pol}. The model calculates the deposition from the NFREYA package [1]. The neutral from the CX deposition is assumed to be ionized in place, a high-density approximation. The fast ions are then assumed to fill a constant angular momentum orbit. And finally, the fast ions immediately assume the form of a dragged down distribution. Transfer rates are then calculated from this distribution function [2]. The differential times are computed from the orbit times and the particle weights in each flux zone (the sampling bin) are proportional to the time spent in the zone. From this information the flux-surface-averaged profiles are obtained and fed into the appropriate transport equation. This procedure is clearly approximate, but accurate enough to help guide experiments. A major advantage is speed: 5000 particles can be processed in under 4s on our fastest LINUX box. This speed adds flexibility by enabling a ''large'' number of predictive studies. Similar approximations, without the accurate orbit calculation presented here, had some success comparing with experiment and TRANSP [3]. Since our procedure does not have multiple CX and relies on disparate time scales, more detailed understanding requires a ''complete'' NB package such as the NUBEAM [4] module, which follows injected fast ions along with their generations until they enter the main thermal distribution.
Not Available
1995-01-01T23:59:59.000Z
Technology Transfer 1995 is intended to inform the US industrial and academic sectors about the many opportunities they have to form partnerships with the US Department of Energy (DOE) for the mutual advantage of the individual institutions, DOE, and the nation as a whole. It also describes some of the growing number of remarkable achievements resulting from such partnerships. These partnership success stories offer ample evidence that Americans are learning how to work together to secure major benefits for the nation--by combining the technological, scientific, and human resources resident in national laboratories with those in industry and academia. The benefits include more and better jobs for Americans, improved productivity and global competitiveness for technology-based industries, and a more efficient government laboratory system.
Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff
2006-10-10T23:59:59.000Z
Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.
Galaxy formation with radiative and chemical feedback
Graziani, L; Schneider, R; Kawata, D; de Bennassuti, M; Maselli, A
2015-01-01T23:59:59.000Z
Here we introduce GAMESH, a novel pipeline which implements self-consistent radiative and chemical feedback in a computational model of galaxy formation. By combining the cosmological chemical-evolution model GAMETE with the radiative transfer code CRASH, GAMESH can post process realistic outputs of a N-body simulation describing the redshift evolution of the forming galaxy. After introducing the GAMESH implementation and its features, we apply the code to a low-resolution N-body simulation of the Milky Way formation and we investigate the combined effects of self-consistent radiative and chemical feedback. Many physical properties, which can be directly compared with observations in the Galaxy and its surrounding satellites, are predicted by the code along the merger-tree assembly. The resulting redshift evolution of the Local Group star formation rates, reionisation and metal enrichment along with the predicted Metallicity Distribution Function of halo stars are critically compared with observations. We dis...
Tropical Cloud Properties and Radiative Heating Profiles
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Mather, James
We have generated a suite of products that includes merged soundings, cloud microphysics, and radiative fluxes and heating profiles. The cloud microphysics is strongly based on the ARM Microbase value added product (Miller et al., 2003). We have made a few changes to the microbase parameterizations to address issues we observed in our initial analysis of the tropical data. The merged sounding product is not directly related to the product developed by ARM but is similar in that it uses the microwave radiometer to scale the radiosonde column water vapor. The radiative fluxes also differ from the ARM BBHRP (Broadband Heating Rate Profile) product in terms of the radiative transfer model and the sampling interval.
Forward and reverse energy transfer in Langmuir-Blodgett multilayers
Sienicki, K. (Universite Laval, Quebec (Canada))
1990-03-08T23:59:59.000Z
The transport of electronic excitations among chromophores randomly distributed in Langmuir-Blodgett multilayers is described. In this theoretical analysis, it has been assumed that excitation energy can be transferred forward and reverse between two-dimensional layers. Fluorescence decays have been calculated for each layer. A numerical analysis of fluorescence decays is given in order to show the influence of reverse energy transfer on photophysical properties of Langmuir-Blodgett multilayers. The discussion of results in connection with recent and future experimental studies is presented.
Heat Transfer in Complex Fluids
Mehrdad Massoudi
2012-01-01T23:59:59.000Z
Amongst the most important constitutive relations in Mechanics, when characterizing the behavior of complex materials, one can identify the stress tensor T, the heat flux vector q (related to heat conduction) and the radiant heating (related to the radiation term in the energy equation). Of course, the expression 'complex materials' is not new. In fact, at least since the publication of the paper by Rivlin & Ericksen (1955), who discussed fluids of complexity (Truesdell & Noll, 1992), to the recently published books (Deshpande et al., 2010), the term complex fluids refers in general to fluid-like materials whose response, namely the stress tensor, is 'non-linear' in some fashion. This non-linearity can manifest itself in variety of forms such as memory effects, yield stress, creep or relaxation, normal-stress differences, etc. The emphasis in this chapter, while focusing on the constitutive modeling of complex fluids, is on granular materials (such as coal) and non-linear fluids (such as coal-slurries). One of the main areas of interest in energy related processes, such as power plants, atomization, alternative fuels, etc., is the use of slurries, specifically coal-water or coal-oil slurries, as the primary fuel. Some studies indicate that the viscosity of coal-water mixtures depends not only on the volume fraction of solids, and the mean size and the size distribution of the coal, but also on the shear rate, since the slurry behaves as shear-rate dependent fluid. There are also studies which indicate that preheating the fuel results in better performance, and as a result of such heating, the viscosity changes. Constitutive modeling of these non-linear fluids, commonly referred to as non-Newtonian fluids, has received much attention. Most of the naturally occurring and synthetic fluids are non-linear fluids, for example, polymer melts, suspensions, blood, coal-water slurries, drilling fluids, mud, etc. It should be noted that sometimes these fluids show Newtonian (linear) behavior for a given range of parameters or geometries; there are many empirical or semi-empirical constitutive equations suggested for these fluids. There have also been many non-linear constitutive relations which have been derived based on the techniques of continuum mechanics. The non-linearities oftentimes appear due to higher gradient terms or time derivatives. When thermal and or chemical effects are also important, the (coupled) momentum and energy equations can give rise to a variety of interesting problems, such as instability, for example the phenomenon of double-diffusive convection in a fluid layer. In Conclusion, we have studied the flow of a compressible (density gradient type) non-linear fluid down an inclined plane, subject to radiation boundary condition. The heat transfer is also considered where a source term, similar to the Arrhenius type reaction, is included. The non-dimensional forms of the equations are solved numerically and the competing effects of conduction, dissipation, heat generation and radiation are discussed. It is observed that the velocity increases rapidly in the region near the inclined surface and is slower in the region near the free surface. Since R{sub 7} is a measure of the heat generation due to chemical reaction, when the reaction is frozen (R{sub 7}=0.0) the temperature distributions would depend only on R{sub 1}, and R{sub 2}, representing the effects of the pressure force developed in the material due to the distribution, R{sub 3} and R{sub 4} viscous dissipation, R{sub 5} the normal stress coefficient, R{sub 6} the measure of the emissivity of the particles to the thermal conductivity, etc. When the flow is not frozen (RP{sub 7} > 0) the temperature inside the flow domain is much higher than those at the inclined and free surfaces. As a result, heat is transferred away from the flow toward both the inclined surface and the free surface with a rate that increases as R{sub 7} increases. For a given temperature, an increase in {zeta} implies that the activation energy is smaller and thus, the reaction ra