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1

Multilevel bioluminescence tomography based on radiative transfer equation  

E-Print Network [OSTI]

, "A fast forward solver of radiative transfer equation," Transport Theory and Statistical Physics 38Multilevel bioluminescence tomography based on radiative transfer equation Part 1: l1 approach for bioluminescence tomography based on radiative transfer equation with the emphasis on improving

Soatto, Stefano

2

Multilevel bioluminescence tomography based on radiative transfer equation  

E-Print Network [OSTI]

Multilevel bioluminescence tomography based on radiative transfer equation Part 2: total variation with both l1 and total- variation norm for bioluminescence tomography based on radiative transfer equation, Radiative Transfer (Dover Publications, 1960). 14. K. M. Case and P. F. PF Zweifel, Linear Transport Theory

Soatto, Stefano

3

Discrete Ordinate Method for Solving Inhomogeneous Vector Radiative Transfer Equation  

E-Print Network [OSTI]

paper.. This type of equation appears when modeling radiative transport in plane parallel media. WeDiscrete Ordinate Method for Solving Inhomogeneous Vector Radiative Transfer Equation We describe here a solution method for equations of the type given by: µ I(,µ) +I(,µ)- () 2 1 -1 Z(,µ,µ )I(,µ )dµ

Pattanaik, Sumanta N.

4

Di usion Approximation of Radiative Transfer Equations in a Channel  

E-Print Network [OSTI]

direction. 1 #12; 1 Introduction Radiative transport equations were #12;rst used to describe the propagationDi#11;usion Approximation of Radiative Transfer Equations in a Channel Guillaume Bal Department by a di#11;usion equation. However, the thickness of the crust is of the order of the transport mean free

Bal, Guillaume

5

Three-dimensional optical tomography with the equation of radiative transfer  

E-Print Network [OSTI]

on a transport-backtransport method applied to the two-dimensional time-dependent equation of radiative transferThree-dimensional optical tomography with the equation of radiative transfer Gassan S. Abdoulaev reconstruction scheme that is based on the time-independent equation of radiative transfer (ERT) and allows

Hielscher, Andreas

6

Multilevel bioluminescence tomography based on radiative transfer equation Part 1: l1 regularization  

E-Print Network [OSTI]

problem for the radiative transport equation, Inv. Prob.the beginning, radiative transport equation (RTE) is used as

Gao, Hao; Zhao, Hongkai

2010-01-01T23:59:59.000Z

7

Solution of the equation of radiative transfer using a NewtonKrylov approach and adaptive mesh refinement  

E-Print Network [OSTI]

Solution of the equation of radiative transfer using a Newton­Krylov approach and adaptive mesh Available online 25 November 2011 Keywords: Radiation transport Discrete ordinates method Finite ordinates method (DOM) and finite-volume method (FVM) are used exten- sively to solve the radiative transfer

Groth, Clinton P. T.

8

Asymptotic Preserving Unified Gas Kinetic Scheme for Grey Radiative Transfer Equations  

E-Print Network [OSTI]

The solutions of radiative transport equations can cover both optical thin and optical thick regimes due equations, where the radiation transport equation is coupled with the material thermal energy equation(2013), 138-156] from a one-dimensional linear radiation transport equation to a nonlinear two

Xu, Kun

9

Modelling of Radiative Transfer in Light Sources  

E-Print Network [OSTI]

of equations . . . . . . . . . . . . . . . . . 19 2.4 Transport equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 3.2 The equation for radiative transfer . . . . . . . . . . . . . . . . . . . . . . . . 44 3Modelling of Radiative Transfer in Light Sources PROEFSCHRIFT ter verkrijging van de graad van

Eindhoven, Technische Universiteit

10

Four Numerical Approaches for Solving the Radiative Transfer Equation in Magnetized White-Dwarf Atmospheres  

E-Print Network [OSTI]

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.

Stefan Jordan; Holger Schmidt

2003-02-04T23:59:59.000Z

11

StaRMAP - A second order staggered grid method for spherical harmonics moment equations of radiative transfer  

E-Print Network [OSTI]

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.

Benjamin Seibold; Martin Frank

2014-06-12T23:59:59.000Z

12

The universal radiative transport equation  

E-Print Network [OSTI]

THE UNIVERSAL RADIATIVE TRANSPORT EQUATION Rudolph W.The Universal Radiative Transport Equation Rudolph W.The various radiative transport equations used in general

Preisendorfer, Rudolph W

1959-01-01T23:59:59.000Z

13

Multi-model Preconditioning for Radiative Transfer Problems  

E-Print Network [OSTI]

, multigrid, radiative transfer, neutron transport, linear Boltzmann equation 2000 MSC: 65N22, 85A25, 65N30 1 and radiation dominated regions must be combined. Since the character of the equation is very different in those of the monochromatic radiative transfer problem leads to a diffusion equation, approximating the radiative transfer

14

Multigroup half space moment approximations to the radiative heat transfer equations q  

E-Print Network [OSTI]

cooling) over astrophysics to combustion (e.g., in gas turbine combustion chambers). Since radiative heat into direction l 2 1; 1. Furthermore, T x; t is the material temperature. The heat conductivity is denoted with the following boundary conditions. For the material temper

Coudire, Yves

15

Journal of Quantitative Spectroscopy & Radiative Transfer 72 (2002) 691713  

E-Print Network [OSTI]

: Equation of radiative transfer; Transport theory; Photon propagation; Scattering media; Discrete.elsevier.com/locate/jqsrt Optical tomography using the time-independent equation of radiative transfer -- Part 1: forward model optical tomographic imaging algorithm that is based on the equation of radiative transfer. Using

Hielscher, Andreas

16

Linear Kinetic Heat Transfer: Moment Equations, Boundary Conditions, and Knudsen  

E-Print Network [OSTI]

] and phonons [6], and the radiative transfer equation [7]. The solution of any kinetic equation is usually][25], radiative transfer [7][26], and phonon transport in crystals [6]. Despite the long history, and success method, and the methods employed in [18][19][20], are based solely on the transport equations in the bulk, and

Struchtrup, Henning

17

A dynamic multi-scale model for transient radiative transfer calculations  

E-Print Network [OSTI]

on the radiative transfer equation (RTE) or the diffusion equation (DE). The RTE is a kinetic transport equation-scale model which couples the transient radiative transfer equation (RTE) and the diffusion equation (DE: transient radiative transfer, multi-scale model, finite volume method, diffusion equation, domain

Boyer, Edmond

18

A FAST MULTILEVEL ALGORITHM FOR THE SOLUTION OF NONLINEAR SYSTEMS OF CONDUCTIVERADIATIVE HEAT TRANSFER EQUATIONS \\Lambda  

E-Print Network [OSTI]

­differential equations that model steady­state combined conductive­radiative heat transfer. This system of equations­Brakhage algorithm. Key words. conductive­radiative heat transfer, multilevel algorithm, compact fixed point problems integro­differential equations that model steady­state combined conductive­radiative heat transfer

19

Journal of Quantitative Spectroscopy & Radiative Transfer 98 (2006) 220237  

E-Print Network [OSTI]

discontinuities associated with the propagation of a radiation front in transient radiation transport. r 2005 q heat flux s geometric path length S source term in the radiative transfer equation t time tc timeJournal of Quantitative Spectroscopy & Radiative Transfer 98 (2006) 220­237 Modified method

Pilon, Laurent

20

A High-Order-Accurate GPU-Based Radiative Transfer Equation Solver for Combustion and Propulsion Applications  

E-Print Network [OSTI]

radiative heat flux through the grid element boundary sstair-case grid. Figure 5 shows the net radiative heat fluxgrid consisted of 6872 tetrahedral elements. The dimensionless radiative heat

He, Xing; Lee, Euntaek; Wilcox, Lucas; Munipalli, Ramakanth; Pilon, Laurent

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Two-frequency radiative transfer and asymptotic solution  

E-Print Network [OSTI]

radiative transfer equation has been derived with full mathematical rigor [13,14]. In the case the wave nature of the process and is not just about energy transport. Hence the governing equation cannotTwo-frequency radiative transfer and asymptotic solution Albert C. Fannjiang* Department

Fannjiang, Albert

22

Journal of Quantitative Spectroscopy & Radiative Transfer 91 (2005) 2746  

E-Print Network [OSTI]

used in the field of transport phenomena simulation, and more specifically in the field of radiative (application of the reciprocity principle to the integral form of the radiative transfer equation), and to netJournal of Quantitative Spectroscopy & Radiative Transfer 91 (2005) 27­46 A boundary-based net

Dufresne, Jean-Louis

23

Radiative Transfer in Interacting Media J.Kenneth Shultis  

E-Print Network [OSTI]

of nuclear energy. Today, radiative transport plays an important role in many other areas besides nuclear, and many others. 1.1 Radiative Transfer Regimes The transport of radiant energy through a medium falls shielding analyses, the radiative transfer equation is linear, and a wealth of numerical techniques exist

Shultis, J. Kenneth

24

Journal of Quantitative Spectroscopy & Radiative Transfer 94 (2005) 357371  

E-Print Network [OSTI]

rights reserved. Keywords: Time dependent radiation transport; M1 approximation; Multigroup models; Mean that solve the radiative transfer equation at a low cost. Among these models, we find diffusion, flux this equation, see [3] and [4]. The first three angular moments of the radiative intensity are defined as Eðn

Coudière, Yves

25

Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 159168  

E-Print Network [OSTI]

-dependence of radiative transport due to the large but ÿnite speed of radiation propagation must be incorporated usion approximation is often used to describe the transient radiation transport [5]. However, recent the fully transient radiative transfer equation. Kumar et al. [8] and Kumar and Mitra [9] were among

Guo, Zhixiong "James"

26

A FAST FORWARD SOLVER OF RADIATIVE TRANSFER HAO GAO AND HONGKAI ZHAO  

E-Print Network [OSTI]

studying the numerical solutions to the radiative transport equation (RTE) or the within-group neutron transport equation [4, 13] in the field of neutron transport [4], atmospheric radiative transfer [1], heatA FAST FORWARD SOLVER OF RADIATIVE TRANSFER EQUATION HAO GAO AND HONGKAI ZHAO Abstract

Soatto, Stefano

27

Project: (version of January 28, 2009) Sparse tensor product methods for radiative transfer  

E-Print Network [OSTI]

simulating a dense gas at very high temperatures, energy transport by means of radiation has to be taken into account. However, as even the non-scattering stationary monochromatic radiative transfer equation s · x. Applying an adaptive sparse discretiza- tion to the radiative transfer equation [1] allows to significantly

Hiptmair, Ralf

28

Radiative Transport Equation in Rotated Reference Frames  

E-Print Network [OSTI]

A novel method for solving the linear radiative transport equation (RTE) in a three-dimensional homogeneous medium is proposed and illustrated with numerical examples. The method can be used with an arbitrary phase function A(s,s') with the constraint that it depends only on the angle between the angular variables s and s'. This corresponds to spherically symmetric (on average) random medium constituents. Boundary conditions are considered in the slab and half-space geometries. The approach developed in this paper is spectral. It allows for the expansion of the solution to the RTE in terms of analytical functions of angular and spatial variables to relatively high orders. The coefficients of this expansion must be computed numerically. However, the computational complexity of this task is much smaller than in the standard method of spherical harmonics. The solutions obtained are especially convenient for solving inverse problems associated with radiative transfer.

George Panasyuk; John C. Schotland; Vadim A. Markel

2005-05-24T23:59:59.000Z

29

E-Print Network 3.0 - analytical radiative-transfer solutions...  

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

In Illumination Engineering Society... . Stephens. On the fundamental solution of the radiative transfer equation. Journal of Astrophysical Research... . A numerical solution to...

30

Modified Method of Characteristics for Transient Radiative Transfer  

E-Print Network [OSTI]

conditions. The radiative transport equation is a hyperbolicTo solve the radiative transport equation for collimated

Katika, Kamal M.; Pilon, Laurent

2006-01-01T23:59:59.000Z

31

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

Kaviany and B.P. Singh, Radiative heat transfer in porousmedia, Advances in Heat Transfer, vol. 23, no. 23, pp. 133Thermal radiation heat transfer, Hemisphere Publishing Co. ,

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

32

Equivalent isotropic scattering formulation for transient short-pulse radiative transfer in anisotropic  

E-Print Network [OSTI]

of the transient short-pulse radiation transport through forward and backward anisotropic scattering planar media time-resolved transmittance.13­15 The complete transient radiative transfer equation has been conEquivalent isotropic scattering formulation for transient short-pulse radiative transfer

Guo, Zhixiong "James"

33

Journal of Quantitative Spectroscopy & Radiative Transfer 104 (2007) 384399  

E-Print Network [OSTI]

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

Pilon, Laurent

34

Radiative transfer with partial coherence in optically thick plasmas Aix-Marseille Universite, CNRS, PIIM UMR 7345, F-13397 Marseille Cedex 20, France  

E-Print Network [OSTI]

approach to address radiative transfer prob- lems involves a transport equation of Boltzmann-type, referred to as "radiative transfer equation", accounting for radiation-matter interaction processes such as spon- taneous the use of a transport theory for photons unavoidable. Opac- ity models for radiative transfer are widely

Paris-Sud XI, Université de

35

Radiative heat transfer in porous uranium dioxide  

SciTech Connect (OSTI)

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.

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

36

A FAST MULTILEVEL ALGORITHM FOR THE SOLUTION OF NONLINEAR SYSTEMS OF CONDUCTIVERADIATIVE HEAT TRANSFER EQUATIONS IN TWO  

E-Print Network [OSTI]

#12; The isotropic, monoenergetic, radiative transport equation is [10], [25], [34], \\Omega \\Delta r r­ differential equations that model steady­state combined conductive­radiative heat transfer in two spaceA FAST MULTILEVEL ALGORITHM FOR THE SOLUTION OF NONLINEAR SYSTEMS OF CONDUCTIVE­RADIATIVE HEAT

37

Radiative heat transfer between dielectric bodies  

E-Print Network [OSTI]

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.

Svend-Age Biehs

2011-03-16T23:59:59.000Z

38

TWO-DIMENSIONAL TRANSIENT RADIATIVE HEAT TRANSFER USING DISCRETE ORDINATES METHOD  

E-Print Network [OSTI]

transport is time-dependent radiative transfer equation. The solution of the hyperbolic transient radiative-pulsed laser radiation interaction and transport within biological tissues. INTRODUCTION With the advent of the short-pulsed laser with the duration of the order of femtoseconds, transient laser radiation transport

Guo, Zhixiong "James"

39

Radiative Heat Transfer between Neighboring Particles  

E-Print Network [OSTI]

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.

Alejandro Manjavacas; F. Javier Garcia de Abajo

2012-01-26T23:59:59.000Z

40

Diffusion Approximation of Radiative Transfer Problems with Guillaume Bal \\Lambda Leonid Ryzhik y  

E-Print Network [OSTI]

Ryzhik y Abstract We derive the diffusion approximation of transport equations with discontinuities at interfaces. The transport equations model the energy density of acoustic waves. The waves are reflected in the high frequency regime by a radiative transfer equation. This model has been first proposed

Ryzhik, Lenya

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Journal of Quantitative Spectroscopy & Radiative Transfer 109 (2008) 727740  

E-Print Network [OSTI]

solution of the Fokker­Planck equation. This equation gives a good approximation to the radiative transport of this method. r 2007 Elsevier Ltd. All rights reserved. Keywords: Radiative transport equation; Fokker tissues is governed by the theory of radiative transport [1]. The radiative transport equation takes

Kim, Arnold D.

42

A 3D radiative transfer framework: II. line transfer problems  

E-Print Network [OSTI]

Higher resolution telescopes as well as 3D numerical simulations will require the development of detailed 3D radiative transfer calculations. Building upon our previous work we extend our method to include both continuum and line transfer. We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in 3D static atmospheres. The scattering problem for line transfer is solved via means of an operator splitting (OS) technique. The formal solution is based on a long-characteristics method. The approximate $\\Lambda$ operator is constructed considering nearest neighbors {\\em exactly}. The code is parallelized over both wavelength and solid angle using the MPI library. We present the results of several test cases with different values of the thermalization parameter and two choices for the temperature structure. The results are directly compared to 1D spherical tests. With our current grid setup the interior resolution is much lower in 3D than in 1D, nevertheless the 3D results agree very well with the well-tested 1D calculations. We show that with relatively simple parallelization that the code scales to very large number of processors which is mandatory for practical applications. Advances in modern computers will make realistic 3D radiative transfer calculations possible in the near future. Our current code scales to very large numbers of processors, but requires larger memory per processor at high spatial resolution.

E. Baron; Peter H. Hauschildt

2007-03-16T23:59:59.000Z

43

PARALLEL COMPUTATIONS OF RADIATIVE HEAT TRANSFER USING THE DISCRETE ORDINATES METHOD  

E-Print Network [OSTI]

the radiative transport equation on parallel computers. Mathematical libraries developed by third parties the discrete ordi- nates method. They observed that the global nature of radiative transport resultedPARALLEL COMPUTATIONS OF RADIATIVE HEAT TRANSFER USING THE DISCRETE ORDINATES METHOD Gautham

Utah, University of

44

Self-consistent scattering theory for the radiative transport equation  

E-Print Network [OSTI]

Self-consistent scattering theory for the radiative transport equation Arnold D. Kim School by the radiative transport equation. We present a theory for the transport equation with an inhomogeneous.5850. 1. INTRODUCTION The radiative transport equation governs light propaga- tion in random media

Kim, Arnold D.

45

A RADIATION TRANSFER SOLVER FOR ATHENA USING SHORT CHARACTERISTICS  

SciTech Connect (OSTI)

We describe the implementation of a module for the Athena magnetohydrodynamics (MHD) code that solves the time-independent, multi-frequency radiative transfer (RT) equation on multidimensional Cartesian simulation domains, including scattering and non-local thermodynamic equilibrium (LTE) effects. The module is based on well known and well tested algorithms developed for modeling stellar atmospheres, including the method of short characteristics to solve the RT equation, accelerated Lambda iteration to handle scattering and non-LTE effects, and parallelization via domain decomposition. The module serves several purposes: it can be used to generate spectra and images, to compute a variable Eddington tensor (VET) for full radiation MHD simulations, and to calculate the heating and cooling source terms in the MHD equations in flows where radiation pressure is small compared with gas pressure. For the latter case, the module is combined with the standard MHD integrators using operator splitting: we describe this approach in detail, including a new constraint on the time step for stability due to radiation diffusion modes. Implementation of the VET method for radiation pressure dominated flows is described in a companion paper. We present results from a suite of test problems for both the RT solver itself and for dynamical problems that include radiative heating and cooling. These tests demonstrate that the radiative transfer solution is accurate and confirm that the operator split method is stable, convergent, and efficient for problems of interest. We demonstrate there is no need to adopt ad hoc assumptions of questionable accuracy to solve RT problems in concert with MHD: the computational cost for our general-purpose module for simple (e.g., LTE gray) problems can be comparable to or less than a single time step of Athena's MHD integrators, and only few times more expensive than that for more general (non-LTE) problems.

Davis, Shane W. [Canadian Institute for Theoretical Astrophysics, Toronto, ON M5S 3H4 (Canada); Stone, James M.; Jiang Yanfei [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

2012-03-01T23:59:59.000Z

46

Boundary transfer matrices and boundary quantum KZ equations  

E-Print Network [OSTI]

A simple relation between inhomogeneous transfer matrices and boundary quantum KZ equations is exhibited for quantum integrable systems with reflecting boundary conditions, analogous to an observation by Gaudin for periodic systems. Thus the boundary quantum KZ equations receive a new motivation. We also derive the commutativity of Sklyanin's boundary transfer matrices by merely imposing appropriate reflection equations, i.e. without using the conditions of crossing symmetry and unitarity of the R-matrix.

Bart Vlaar

2014-10-31T23:59:59.000Z

47

RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS  

E-Print Network [OSTI]

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

48

RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda  

E-Print Network [OSTI]

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

49

Mpemba effect, Newton cooling law and heat transfer equation  

E-Print Network [OSTI]

In this work we suggest a simple theoretical solution of the Mpemba effect in full agreement with known experimental data. This solution follows simply as an especial approximation (linearization) of the usual heat (transfer) equation, precisely linearization of the second derivation of the space part of the temperature function (as it is well-known Newton cooling law can be considered as the effective approximation of the heat (transfer) equation for constant space part of the temperature function).

Vladan Pankovic; Darko V. Kapor

2012-12-11T23:59:59.000Z

50

Complete radiative terms for the electron/electronic energy equation  

SciTech Connect (OSTI)

A derivation of the radiative terms in the electron/electronic energy equation is presented, properly accounting for the effects of absorption and emission of radiation on the individual energy modes of the gas. This electron/electronic energy equation with the complete radiative terms has successfully been used to model the radiation-dominated precursor ahead of the bow shock of a hypersonic vehicle entering the Earth`s atmosphere. 8 refs.

Stanley, S.A.; Carlson, L.A. [Univ of California, San Diego, CA (United States)

1994-10-01T23:59:59.000Z

51

Journal of Quantitative Spectroscopy & Radiative Transfer 64 (2000) 255}273  

E-Print Network [OSTI]

s is the minimum of the total cross-section set, and consider the (vector) transport equation * * ( , )# ( , )" 1 2Journal of Quantitative Spectroscopy & Radiative Transfer 64 (2000) 255}273 A discrete-ordinates solution for multigroup transport theory with upscattering C.E. Siewert Mathematics Department, North

Siewert, Charles E.

52

ht. 1. Han Mass 7h&r. Vol. 13, pp. 13494357. Pergamon Pra 1970. PhIed in Great Britain RADIATIVE TRANSFER IN A CONSERVATIVE  

E-Print Network [OSTI]

involving radiative transport and wall temperature slip in a finite, absorbing, emitting gray medium, equation of transfer then equation (4) reduces to the simpler form where Z(z,Zl)is the radiation intensity, Zlis the In their work on radiative transport and wall direction cosine (as measured from the positive

Siewert, Charles E.

53

PRECONDITIONED BI-CONJUGATE GRADIENT METHOD FOR RADIATIVE TRANSFER IN SPHERICAL MEDIA  

SciTech Connect (OSTI)

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.

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

54

COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS  

SciTech Connect (OSTI)

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.

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

55

Enhanced radiative heat transfer between nanostructured gold plates  

E-Print Network [OSTI]

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.

R. Gurout; 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

56

14 Three-Dimensional Radiative Transfer in Vegetation Canopies  

E-Print Network [OSTI]

transport equa- tion. This equation has a very simple physical interpretation; it is a mathematical to correctly de- scribe the photon transport. Second, the radiation regime is substantially influenced, 1981, p. 144). This allows the transport equation to relate micro-scale properties of the medium

Myneni, Ranga B.

57

Singular eigenfunctions for the three-dimensional radiative transport equation  

E-Print Network [OSTI]

Case's method obtains solutions to the radiative transport equation as superpositions of elementary solutions when the specific intensity depends on one spatial variable. In this paper, we find elementary solutions when the specific intensity depends on three spatial variables in three-dimensional space. By using the reference frame whose z-axis lies in the direction of the wave vector, the angular part of each elementary solution becomes the singular eigenfunction for the one-dimensional radiative transport equation. Thus Case's method is generalized.

Manabu Machida

2013-09-07T23:59:59.000Z

58

Numerical methods for multidimensional radiative transfer  

E-Print Network [OSTI]

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

59

Debris Disk Radiative Transfer Simulation Tool (DDS)  

E-Print Network [OSTI]

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

S. Wolf; L. A. Hillenbrand

2005-06-17T23:59:59.000Z

60

Radiative transport limit for the random Schrdinger equation  

E-Print Network [OSTI]

We give a detailed mathematical analysis of the radiative transport limit for the average phase space density of solutions of the Schroedinger equation with time dependent random potential. Our derivation is based on the construction of an approximate martingale for the random Wigner distribution.

Guillaume Bal; George Papanicolaou; Leonid Ryzhik

2001-08-14T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

RADIATIVE TRANSFER SIMULATIONS OF NEUTRON STAR MERGER EJECTA  

SciTech Connect (OSTI)

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.

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

62

Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering and ModeCoupling  

E-Print Network [OSTI]

systematically to derive the radiative transport equations that describe the evolution of acoustic correlation : : : : : : : : : : : : : : : : : : : : 8 3.2 The radiative transport equations : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 9 of the radiative transport equations 21 B Derivation of the diffusion equation without flow­straining 23 C

Ryzhik, Lenya

63

FFT-based Computation of the Bioheat Transfer Equation for the HCC Ultrasound Surgery Therapy Modeling  

E-Print Network [OSTI]

' bioheat transfer equation which is generally solved by a finite difference method. In this paper we will present a method where the bioheat transfer equation can be algebraically solved after a Fourier will be shown and compared with the finite difference method. I. INTRODUCTION At an early stage

Boyer, Edmond

64

Application of Stochastic Radiative Transfer Theory to the ARM Cloud-Radiative Parameterization Problem  

SciTech Connect (OSTI)

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.

Dana E. Veron

2012-04-09T23:59:59.000Z

65

Application of Stochastic Radiative Transfer Theory to the ARM Cloud-Radiative Parameterization Problem  

SciTech Connect (OSTI)

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.

Veron, Dana E

2009-03-12T23:59:59.000Z

66

HYDRODYNAMIC LIMITS FOR KINETIC EQUATIONS AND THE DIFFUSIVE APPROXIMATION OF RADIATIVE  

E-Print Network [OSTI]

HYDRODYNAMIC LIMITS FOR KINETIC EQUATIONS AND THE DIFFUSIVE APPROXIMATION OF RADIATIVE TRANSPORT . The radiative transport equations, satisfied by the Wigner function for random acoustic waves, present#usive approximation of the radiative transport equation. 1. Introduction We consider a class of kinetic models

Tzavaras, Athanasios E.

67

Radiative heat transfer in 2D Dirac materials  

E-Print Network [OSTI]

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.

Pablo Rodriguez-Lopez; Wang-Kong Tse; Diego A. R. Dalvit

2015-02-02T23:59:59.000Z

68

Validation of 3D Radiative Transfer in Coastal-Ocean Water Systems as Modeled by DIRSIG  

E-Print Network [OSTI]

Validation of 3D Radiative Transfer in Coastal-Ocean Water Systems as Modeled by DIRSIG FOR IMAGING SCIENCE Title of Dissertation: Validation of 3D Radiative Transfer in Coastal-Ocean Water Systems. Signature Date 3 #12;Validation of 3D Radiative Transfer in Coastal-Ocean Water Systems as Modeled by DIRSIG

Salvaggio, Carl

69

Radiative heat transfer in a hydrous mantle transition zone Sylvia-Monique Thomas a,n  

E-Print Network [OSTI]

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

Jacobsen, Steven D.

70

Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

71

Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application  

E-Print Network [OSTI]

Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application to Crystal University of New York at Stony Brook Stony Brook N.Y. 11794 ABSTRACT Radiative heat transfer plays simulating radiative heat transfer in the crystal and in the region above the melt containing gas under

New York at Stoney Brook, State University of

72

Heat transfer through a water spray curtain under the effect of a strong radiative source  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

73

The radiative and combined mode heat transfer within the L-shaped nonhomogeneous and nongray participating media  

SciTech Connect (OSTI)

The solutions of pure radiative and combined radiative and conductive heat transfer within a L-shaped enclosure are presented. The enclosure contains a mixture of pulverized carbon particles, CO{sub 2}, and N{sub 2}. Three different types of problems are solved: homogeneous radiative properties, nonhomogeneous radiative properties, and combined conduction-radiation problem with nonhomogeneous radiative properties. To obtain solutions for these problems, the YIX method is used. The YIX quadrature uses piecewise constant interpolation of the integrands. To handle the L-shaped enclosure, an ad hoc approach of searching the struck surface node in the line-of-sight is developed. The general approach of handling any arbitrary complex geometry is briefly described. A single point, implicit, quasi-Newton scheme is used to solve the energy equation when both the radiation and conduction heat transfer modes are present. The quasi-Newton works well for a wide range of dimensionless conduction-radiation parameter except when the parameter is less than 0.2, i.e., radiation is the dominant heat transfer mode.

Hsu, P.F. [Florida Inst. of Tech., Melbourne, FL (United States). Mechanical and Aerospace Engineering Programs; Tan, Z. [Univ. of Texas, Austin, TX (United States). Aerospace Engineering and Engineering Mechanics Dept.

1996-11-01T23:59:59.000Z

74

Analytical Green's function of the radiative transfer radiance for the infinite medium  

SciTech Connect (OSTI)

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.

Liemert, Andre; Kienle, Alwin [Institut fuer Lasertechnologien in der Medizin und Messtechnik, Helmholtzstrasse12, D-89081 Ulm (Germany)

2011-03-15T23:59:59.000Z

75

Development of a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI)  

SciTech Connect (OSTI)

Satellite-observed radiance is a nonlinear functional of surface properties and atmospheric temperature and absorbing gas profiles as described by the radiative transfer equation (RTE). In the era of hyperspectral sounders with thousands of high-resolution channels, the computation of the radiative transfer model becomes more time-consuming. The radiative transfer model performance in operational numerical weather prediction systems still limits the number of channels we can use in hyperspectral sounders to only a few hundreds. To take the full advantage of such high-resolution infrared observations, a computationally efficient radiative transfer model is needed to facilitate satellite data assimilation. In recent years the programmable commodity graphics processing unit (GPU) has evolved into a highly parallel, multi-threaded, many-core processor with tremendous computational speed and very high memory bandwidth. The radiative transfer model is very suitable for the GPU implementation to take advantage of the hardware's efficiency and parallelism where radiances of many channels can be calculated in parallel in GPUs. In this paper, we develop a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI) launched in 2006 onboard the first European meteorological polar-orbiting satellites, METOP-A. Each IASI spectrum has 8461 spectral channels. The IASI radiative transfer model consists of three modules. The first module for computing the regression predictors takes less than 0.004% of CPU time, while the second module for transmittance computation and the third module for radiance computation take approximately 92.5% and 7.5%, respectively. Our GPU-based IASI radiative transfer model is developed to run on a low-cost personal supercomputer with four GPUs with total 960 compute cores, delivering near 4 TFlops theoretical peak performance. By massively parallelizing the second and third modules, we reached 364x speedup for 1 GPU and 1455x speedup for all 4 GPUs, both with respect to the original CPU-based single-threaded Fortran code with the -O{sub 2} compiling optimization. The significant 1455x speedup using a computer with four GPUs means that the proposed GPU-based high-performance forward model is able to compute one day's amount of 1,296,000 IASI spectra within nearly 10 min, whereas the original single CPU-based version will impractically take more than 10 days. This model runs over 80% of the theoretical memory bandwidth with asynchronous data transfer. A novel CPU-GPU pipeline implementation of the IASI radiative transfer model is proposed. The GPU-based high-performance IASI radiative transfer model is suitable for the assimilation of the IASI radiance observations into the operational numerical weather forecast model.

Huang Bormin, E-mail: bormin@ssec.wisc.ed [Space Science and Engineering Center, University of Wisconsin, Madison (United States); Mielikainen, Jarno [Department of Computer Science, University of Eastern Finland, Kuopio (Finland); Oh, Hyunjong; Allen Huang, Hung-Lung [Space Science and Engineering Center, University of Wisconsin, Madison (United States)

2011-03-20T23:59:59.000Z

76

HYDRODYNAMIC LIMITS FOR KINETIC EQUATIONS AND THE DIFFUSIVE APPROXIMATION OF RADIATIVE  

E-Print Network [OSTI]

HYDRODYNAMIC LIMITS FOR KINETIC EQUATIONS AND THE DIFFUSIVE APPROXIMATION OF RADIATIVE TRANSPORT of the radiative transport equation. 1. Introduction We consider a class of kinetic models equipped with a single. A general compactness frame- work is obtained for the diffusive scaling in L1 . The radiative transport

Tzavaras, Athanasios E.

77

12.815 Atmospheric Radiation, Fall 2005  

E-Print Network [OSTI]

Introduction to the physics of atmospheric radiation and remote sensing including use of computer codes. Radiative transfer equation including emission and scattering, spectroscopy, Mie theory, and numerical solutions. ...

Prinn, Ronald G.

78

Magnetic storm acceleration of radiation belt electrons observed by the Scintillating Fibre Detector (SFD) onboard EQUATOR-S  

E-Print Network [OSTI]

on the 50067300 km, 4 inclination EQUATOR-S orbit show that the increase of the energetic electron ux of electrons in the outer radiation belt has been attributed to Pc 5 band ULF waves excited by high speed solar wind ow associated with magnetic storms (Rostoker et al., 1998). The main features

Paris-Sud XI, Universit de

79

3D Atmospheric Radiative Transfer for Cloud System-Resolving Models: Forward Modelling and Observations  

SciTech Connect (OSTI)

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.

Howard Barker; Jason Cole

2012-05-17T23:59:59.000Z

80

Theoretical and Numerical Analysis of Polarization for Time Dependent Radiative  

E-Print Network [OSTI]

transport equation with respect to the polariza- tion parameters solve the matrix-valued radiative transferTheoretical and Numerical Analysis of Polarization for Time Dependent Radiative Transfer Equations@math.stanford.edu Abstract We consider the matrix-valued radiative transfer equations for the Stokes param- eters

Bal, Guillaume

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

A GENERAL CIRCULATION MODEL FOR GASEOUS EXOPLANETS WITH DOUBLE-GRAY RADIATIVE TRANSFER  

SciTech Connect (OSTI)

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.

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

82

RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS  

E-Print Network [OSTI]

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

Guo, Zhixiong "James"

83

Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering, Straining, and Mode-Coupling  

E-Print Network [OSTI]

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

Fannjiang, Albert

84

Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method  

E-Print Network [OSTI]

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

Yuen, Walter W.

85

Glass foams: formation, transport properties, and heat, mass, and radiation transfer  

E-Print Network [OSTI]

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

Pilon, Laurent

86

On exact and perturbation solutions to nonlinear equations for heat transfer models  

E-Print Network [OSTI]

We analyze some exact and approximate solutions to nonlinear equations for heat transfer models. We prove that recent results derived from a method based on Lie algebras are either trivial or wrong. We test a simple analytical expression based on the hypervirial theorem and also discuss earlier perturbation results.

Francisco M. Fernndez

2009-11-03T23:59:59.000Z

87

FFT-based computation of the bioheat transfer equation for the HCC ultrasound surgery therapy modeling  

E-Print Network [OSTI]

is generally solved by a finite' difference method. In this paper we will present a method where the bioheat. The implementation and boundary conditions of this method will be shown and compared with the finite difference method. Author Keywords hyperthermia ; Bioheat Transfer Equation ; high intensity ultrasound

Boyer, Edmond

88

Surface-Phonon Polariton Contribution to Nanoscale Radiative Heat Transfer. Emmanuel Rousseau  

E-Print Network [OSTI]

Surface-Phonon Polariton Contribution to Nanoscale Radiative Heat Transfer. Emmanuel Rousseau-sud Campus Polytechnique RD 128 91127 Palaiseau cedex, France Heat transfer between two plates of polar far-field value. In this article, we show that nanoscale heat transfer is dominated by the coupling

Paris-Sud XI, Université de

89

Parameterization and Analysis of 3-D Solar Radiative Transfer in Clouds: Final Report  

SciTech Connect (OSTI)

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.

Jerry Y. Harrington

2012-09-21T23:59:59.000Z

90

Diffusion Approximation of Radiative Transfer Problems with Guillaume Bal \\Lambda Leonid Ryzhik y  

E-Print Network [OSTI]

propagation. The radiative transport equation for the evolution of the average phase space energy density a Ryzhik y September 16, 1998 Abstract We derive the diffusion approximation of transport equations with discontinuities at interfaces. The transport equations model the energy density of acoustic waves. The waves

Bal, Guillaume

91

Graphene-assisted near-field radiative heat transfer between corrugated polar materials  

SciTech Connect (OSTI)

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.

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

92

Numerical simulation of three-dimensional combined convective radiative heat transfer in rectangular channels  

E-Print Network [OSTI]

This dissertation presents a numerical simulation of three-dimensional flow and heat transfer in a channel with a backward-facing step. Flow was considered to be steady, incompressible, and laminar. The flow medium was treated to be radiatively...

Ko, Min Seok

2009-05-15T23:59:59.000Z

93

Near-field thermal radiation transfer controlled by plasmons in graphene  

E-Print Network [OSTI]

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 ...

Ilic, Ognjen

94

Microwave radiative transfer in the mixed-phase regions of tropical rainfall  

E-Print Network [OSTI]

on an RTM. To accomplish this, we examined data taken by the Convair-580 aircraft during the KWAJEX (Kwajalein Experiment). In order to calculate radiative transfer, the AMMR (Airborne Multi-channel Microwave Radiometer) data were combined with radiosonde...

Jin, Kyoung-Wook

2001-01-01T23:59:59.000Z

95

Uniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations  

E-Print Network [OSTI]

, radiative transfer, and transport equations for waves in random media, have a diffusive scaling that leads #12; 1. Introduction Many transport equations, such as the neutron transport [CZ], radiative transferUniformly Accurate Diffusive Relaxation Schemes for Multiscale Transport Equations Shi JIN y

96

E-Print Network 3.0 - anisotropic k-shell radiation Sample Search...  

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

Summary: media. Specifically, we provide: (i) an anisotropic version of the radiative transport equation (RTE... scattering model in section 4. 3 Anisotropic Radiative Transfer The...

97

Conservative Moment Equations for Neutrino Radiation Transport with Limited Relativity  

E-Print Network [OSTI]

We derive conservative, multidimensional, energy-dependent moment equations for neutrino transport in core-collapse supernovae and related astrophysical systems, with particular attention to the consistency of conservative four-momentum and lepton number transport equations. After taking angular moments of conservative formulations of the general relativistic Boltzmann equation, we specialize to a conformally flat spacetime, which also serves as the basis for four further limits. Two of these---the multidimensional special relativistic case, and a conformally flat formulation of the spherically symmetric general relativistic case---are given in appendices for the sake of comparison with extant literature. The third limit is a weak-field, `pseudo-Newtonian' approach \\citep{kim_etal_2009,kim_etal_2012} in which the source of the gravitational potential includes the trace of the stress-energy tensor (rather than just the mass density), and all orders in fluid velocity $v$ are retained. Our primary interest here ...

Endeve, Eirik; Mezzacappa, Anthony

2012-01-01T23:59:59.000Z

98

Author's personal copy Radiation transfer in photobiological carbon dioxide fixation and fuel  

E-Print Network [OSTI]

and fuel production by microalgae Laurent Pilon a,, Halil Berberoglu b,1 , Razmig Kandilian a a Mechanical Scattering Chlorophyll Ocean optics Hydrogen Lipid production Biofuels Cyanobacteria Light transfer a b s t r to photobiologically fixate carbon dioxide and convert solar energy into biofuels. Thus, careful radiation transfer

Pilon, Laurent

99

Perturbation theory for the diffusion equation by use of the moments of the generalized  

E-Print Network [OSTI]

of the radiative transfer equation and the solution of the Fredholm equation of the second kind given a suitable solution of the radiative transfer equation for the calculation of the multiple integrals or on transport theory. While analyti- cal solutions of the diffusion equation (DE) are found in the literature

Fantini, Sergio

100

accelerated radiative transfer: Topics by E-print Network  

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

Dominated Outflows Astrophysics (arXiv) Summary: Plasma outflows from gamma-ray bursts (GRB), pulsar winds, relativistic jets, and ultra-intense laser targets radiate...

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Journal of Quantitative Spectroscopy & Radiative Transfer 64 (2000) 219}226  

E-Print Network [OSTI]

of the discrete-ordinates approximation to the transport equation in plane geometry. The Green's function of papers [1}3] concerning radiation-transport problems in plane geometry, linear-algebra techniques were of the Fourier-component (m50) problems basic to the general azimuth-dependent transport equation [6], and since

Siewert, Charles E.

102

Correlation, entropy, and information transfer in black hole radiation  

E-Print Network [OSTI]

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.

Baocheng Zhang; Qingyu Cai; Mingsheng Zhan; Li You

2014-03-28T23:59:59.000Z

103

Trace formulae for non-equilibrium Casimir interactions, heat radiation and heat transfer for arbitrary objects  

E-Print Network [OSTI]

We present a detailed derivation of heat radiation, heat transfer and (Casimir) interactions for N arbitrary objects in the framework of fluctuational electrodynamics in thermal non-equilibrium. The results can be expressed as basis-independent trace formulae in terms of the scattering operators of the individual objects. We prove that heat radiation of a single object is positive, and that heat transfer (for two arbitrary passive objects) is from the hotter to a colder body. The heat transferred is also symmetric, exactly reversed if the two temperatures are exchanged. Introducing partial wave-expansions, we transform the results for radiation, transfer and forces into traces of matrices that can be evaluated in any basis, analogous to the equilibrium Casimir force. The method is illustrated by (re)deriving the heat radiation of a plate, a sphere and a cylinder. We analyze the radiation of a sphere for different materials, emphasizing that a simplification often employed for metallic nano-spheres is typically invalid. We derive asymptotic formulae for heat transfer and non-equilibrium interactions for the cases of a sphere in front a plate and for two spheres, extending previous results. As an example, we show that a hot nano-sphere can levitate above a plate with the repulsive non-equilibrium force overcoming gravity -- an effect that is not due to radiation pressure.

Matthias Krger; Giuseppe Bimonte; Thorsten Emig; Mehran Kardar

2012-07-16T23:59:59.000Z

104

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear EnergyTransfer Ionizing Radiation Exposure  

E-Print Network [OSTI]

Human In vivo Dose-Response to Controlled, Low-Dose Low Linear EnergyTransfer Ionizing Radiation Purpose: The effect of low doses of low ^ linear energy transfer (photon) ionizing radiation (LDIR, and pathway. Conclusions: These results show for the first time that low doses of radiation have an identifi

Rocke, David M.

105

Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 239248  

E-Print Network [OSTI]

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

Guo, Zhixiong "James"

106

Stochastic Radiative Transfer in Multilayer Broken Clouds. Part II: Validation Tests  

SciTech Connect (OSTI)

In the second part of our two-part paper we estimated the accuracy and robustness of the approximated equations for the mean radiance that were derived in Part I. In our analysis we used the three-dimensional (3D) cloud fields provided by (i) the stochastic Boolean model, (ii) large-eddy simulation model and (iii) satellite cloud retrieval. The accuracy of the obtained equations was evaluated by comparing the ensemble-averaged radiative properties that were obtained by the numerical averaging method (reference) and the analytical averaging method (approximation). The robustness of these equations was estimated by comparing the domain-averaged radiative properties obtained by using (i) the full 3D cloud structure (reference) and (ii) the bulk cloud statistics (approximation). It was shown that the approximated equations could provide reasonable accuracy ({approx}15%) for both the ensemble-averaged and domain-averaged radiative properties.

Kassianov, Evgueni I.; Ackerman, Thomas P.; Marchand, Roger T.; Ovtchinnikov, Mikhail

2003-04-01T23:59:59.000Z

107

Parameterization and analysis of 3-D radiative transfer in clouds  

SciTech Connect (OSTI)

This report provides a summary of major accomplishments from the project. The project examines the impact of radiative interactions between neighboring atmospheric columns, for example clouds scattering extra sunlight toward nearby clear areas. While most current cloud models donâ??t consider these interactions and instead treat sunlight in each atmospheric column separately, the resulting uncertainties have remained unknown. This project has provided the first estimates on the way average solar heating is affected by interactions between nearby columns. These estimates have been obtained by combining several years of cloud observations at three DOE Atmospheric Radiation Measurement (ARM) Climate Research Facility sites (in Alaska, Oklahoma, and Papua New Guinea) with simulations of solar radiation around the observed clouds. The importance of radiative interactions between atmospheric columns was evaluated by contrasting simulations that included the interactions with those that did not. This study provides lower-bound estimates for radiative interactions: It cannot consider interactions in cross-wind direction, because it uses two-dimensional vertical cross-sections through clouds that were observed by instruments looking straight up as clouds drifted aloft. Data from new DOE scanning radars will allow future radiative studies to consider the full three-dimensional nature of radiative processes. The results reveal that two-dimensional radiative interactions increase overall day-and-night average solar heating by about 0.3, 1.2, and 4.1 Watts per meter square at the three sites, respectively. This increase grows further if one considers that most large-domain cloud simulations have resolutions that cannot specify small-scale cloud variability. For example, the increases in solar heating mentioned above roughly double for a fairly typical model resolution of 1 km. The study also examined the factors that shape radiative interactions between atmospheric columns and found that local effects were often much larger than the overall values mentioned above, and were especially large for high sun and near convective clouds such as cumulus. The study also found that statistical methods such as neural networks appear promising for enabling cloud models to consider radiative interactions between nearby atmospheric columns. Finally, through collaboration with German scientists, the project found that new methods (especially one called â??stepwise krigingâ?) show great promise in filling gaps between cloud radar scans. If applied to data from the new DOE scanning cloud radars, these methods can yield large, continuous three-dimensional cloud structures for future radiative simulations.

Varnai, Tamas

2012-03-16T23:59:59.000Z

108

OUMBE, Armel, WALD, Lucien, BLANC, Philippe, and SCHROEDTER-HOMSCHEIDT, Marion. Exploitation of radiative transfer model for assessing solar radiation: the relative importance of atmospheric  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

109

The piecewise linear discontinuous finite element method applied to the RZ and XYZ transport equations  

E-Print Network [OSTI]

of the Piecewise Linear Discontinuous Finite Element Method (PWLD) applied to the particle transport equation in two-dimensional cylindrical (RZ) and three-dimensional Cartesian (XYZ) geometries. We have designed this method to be applicable to radiative... ..................................................... 12 Coupling the radiation transport equation to the Euler equations.. 16 Limit of the radiative transfer equations ........................................ 19 Summary...

Bailey, Teresa S

2008-10-10T23:59:59.000Z

110

Radiation Hydrodynamics in Kerr Spacetime: Equations without Coordinate Singularity at the Event Horizon  

E-Print Network [OSTI]

Equations of fully general relativistic radiation hydrodynamics around a rotating black hole are derived by using the Kerr-Schild coordinate where there is no coordinate singularity at the event horizon. Since the radiation interacts with matter moving with relativistic velocities near the event horizon, the interplay between the radiation and the matter should be described fully relativistically. In the formalism used in this study, while the interactions between matter and radiation are introduced in the comoving frame, the equations and the equations and the derivatives for the description of the global evolution of both matter and the radiation are given in the Kerr-Schild frame (KSF) which is a frame fixed to the coordinate describing the central black hole. As a frame fixed to the coordinate, we use the locally non-rotating reference frame (LNRF) representing a radially falling frame when the Kerr-Schild coordinate is used. Around the rotating black hole, both the matter and the radiation are affected by the frame-dragging effects.

Rohta Takahashi

2007-10-18T23:59:59.000Z

111

1 Copyright 2012 by ASME Proceedings of the ASME 2012 Summer Heat Transfer Conference  

E-Print Network [OSTI]

with biological media during biomedical laser therapeutic applications [1-6], involve the transport of radiative of radiative transfer, accurate solutions of the Equation of Radiative Transfer (ERT) are required. The ERT 8-12, 2012, Rio Grande, Puerto Rico HT2012-58307 NORMALIZATION FOR ULTRAFAST RADIATIVE TRANSFER

Guo, Zhixiong "James"

112

Heat transfer including radiation and slag particles evolution in MHD channel-I  

SciTech Connect (OSTI)

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.

Im, K.H.; Ahluwalia, R.K.

1980-01-01T23:59:59.000Z

113

Second order equation of motion for electromagnetic radiation back-reaction  

E-Print Network [OSTI]

We take the viewpoint that the physically acceptable solutions of the Lorentz-Dirac equation for radiation back-reaction are actually determined by a second order equation of motion in such a way that the self-force can be given as a function of spacetime location and velocity. This self-force function turns out to be determined by a first order partial differential equation. In view of possible practical difficulty in solving that partial differential equation, we propose two iteration methods, too, for obtaining the self-force function. For two example systems, the second order equation of motion is obtained exactly in the nonrelativistic regime via each of the three methods, and the three results are found to coincide. We reveal that, for both systems, back-reaction induces a damping proportional to velocity and, in addition, it decreases the effect of the external force.

Tams Matolcsi; Tams Flp; Mihly Weiner

2014-10-26T23:59:59.000Z

114

Radiative Transfer in Photocatalytic Systems Matteo Pasquali and Francesco Santarelli  

E-Print Network [OSTI]

; these components are usually anatase titanium dioxide, near-ultraviolet radiation, and oxygen, respectively as adsorption, chemical oxida- tion, and biodegradation) in that PCO can completely de- grade many classes of toxic organic compounds, forming only carbon dioxide and mineral acids, and it can achieve this within

Natelson, Douglas

115

Author's personal copy Radiative heat transfer in enhanced hydrogen  

E-Print Network [OSTI]

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 and the glass samples. In brief, the radiation emitted by the incandescent lamp is concentrated between 0

Pilon, Laurent

116

Journal of Quantitative Spectroscopy & Radiative Transfer 99 (2006) 341348  

E-Print Network [OSTI]

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 B forces implode the wire array, which generates nearly 2 MJ of X-rays in o

2006-01-01T23:59:59.000Z

117

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinementEtching.348 270 300 219Improvements to the SHDOM Radiative

118

BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1  

E-Print Network [OSTI]

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

Naylor, David A.

119

An Efficient Approach for Optical Radiative Transfer Tomography using the Spherical Harmonics Discrete Ordinates Method  

E-Print Network [OSTI]

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.

Levis, Aviad; Aides, Amit; Davis, Anthony B

2015-01-01T23:59:59.000Z

120

Shape-independent limits to near-field radiative heat transfer  

E-Print Network [OSTI]

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...

Miller, Owen D; Rodriguez, Alejandro W

2015-01-01T23:59:59.000Z

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121

On linearization and preconditioning for radiation diffusion coupled to material thermal conduction equations  

SciTech Connect (OSTI)

Jacobian-free NewtonKrylov (JFNK) method is an effective algorithm for solving large scale nonlinear equations. One of the most important advantages of JFNK method is that there is no necessity to form and store the Jacobian matrix of the nonlinear system when JFNK method is employed. However, an approximation of the Jacobian is needed for the purpose of preconditioning. In this paper, JFNK method is employed to solve a class of non-equilibrium radiation diffusion coupled to material thermal conduction equations, and two preconditioners are designed by linearizing the equations in two methods. Numerical results show that the two preconditioning methods can improve the convergence behavior and efficiency of JFNK method.

Feng, Tao, E-mail: fengtao2@mail.ustc.edu.cn [School of Mathematical Sciences, University of Science and Technology of China, Hefei 230052 (China) [School of Mathematical Sciences, University of Science and Technology of China, Hefei 230052 (China); Graduate School of China Academy Engineering Physics, Beijing 100083 (China); An, Hengbin, E-mail: an_hengbin@iapcm.ac.cn [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Yu, Xijun, E-mail: yuxj@iapcm.ac.cn [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China)] [National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Li, Qin, E-mail: liqin@lsec.cc.ac.cn [Chinese Academy of Mathematics and Systems Science, Beijing 100190 (China)] [Chinese Academy of Mathematics and Systems Science, Beijing 100190 (China); Zhang, Rongpei, E-mail: zhangrongpei@163.com [Graduate School of China Academy Engineering Physics, Beijing 100083 (China)] [Graduate School of China Academy Engineering Physics, Beijing 100083 (China)

2013-03-01T23:59:59.000Z

122

Effect of radiative heat transfer on the coagulation dynamics of combustion-generated particles  

SciTech Connect (OSTI)

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.

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

123

Clouds in the atmospheres of extrasolar planets. IV. On the scattering greenhouse effect of CO2 ice particles: Numerical radiative transfer studies  

E-Print Network [OSTI]

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...

Kitzmann, D; Rauer, H

2013-01-01T23:59:59.000Z

124

Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials  

E-Print Network [OSTI]

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.

Svend-Age Biehs

2011-03-15T23:59:59.000Z

125

Including radiative heat transfer and reaction quenching in modeling a Claus plant waste heat boiler  

SciTech Connect (OSTI)

Due to increasingly stringent sulfur emission regulations, improvements are necessary in the modified Claus process. A recently proposed model by Nasato et al. for the Claus plant waste heat boiler (WHB) is improved by including radiative heat transfer, which yields significant changes in the predicted heat flux and the temperature profile along the WHB tube, leading to a faster quenching of chemical reactions. For the WHB considered, radiation accounts for approximately 20% of the heat transferred by convection alone. More importantly, operating the WHB at a higher gas mass flux is shown to enhance reaction quenching, resulting in a doubling of the predicted hydrogen flow rate. This increase in hydrogen flow rate is sufficient to completely meet the hydrogen requirement of the H[sub 2]S recovery process considered, which would eliminate the need for a hydrogen plant.

Karan, K.; Mehrotra, A.K.; Behie, L.A. (Univ. of Calgary, Alberta (Canada). Dept. of Chemical and Petroleum Engineering)

1994-11-01T23:59:59.000Z

126

Non-contact pumping of light emitters via non-radiative energy transfer  

DOE Patents [OSTI]

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.

Klimov, Victor I. (Los Alamos, NM); Achermann, Marc (Los Alamos, NM)

2010-01-05T23:59:59.000Z

127

Development and adaptation of conduction and radiation heat-transfer computer codes for the CFTL. [Core Flow Test Loop; RODCON; HOTTEL  

SciTech Connect (OSTI)

RODCON and HOTTEL are two computational methods used to calculate thermal and radiation heat transfer for the Core Flow Test Loop (CFTL) analysis efforts. RODCON was developed at ORNL to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the CFTL. RODCON solves the time-dependent heat transfer equation in two-dimensional (R angle) cylindrical coordinates at an axial plane with user-specified radial material zones and time- and position-variant surface conditions at the FRS periphery. Symmetry of the FRS periphery boundary conditions is not necessary. The governing elliptic, partial differential heat equation is cast into a fully implicit, finite-difference form by approximating the derivatives with a forward-differencing scheme with variable mesh spacing. The heat conduction path is circumferentially complete, and the potential mathematical problem at the rod center can be effectively ignored. HOTTEL is a revision of an algorithm developed by C.B. Baxi at the General Atomic Company (GAC) to be used in calculating radiation heat transfer in a rod bundle enclosed in a hexagonal duct. HOTTEL uses geometric view factors, surface emissivities, and surface areas to calculate the gray-body or composite view factors in an enclosure having multiple reflections in a nonparticipating medium.

Conklin, J.C.

1981-08-01T23:59:59.000Z

128

Heat transfer performance of an external receiver pipe under unilateral concentrated solar radiation  

SciTech Connect (OSTI)

The heat transfer and absorption characteristics of an external receiver pipe under unilateral concentrated solar radiation are theoretically investigated. Since the heat loss ratio of the infrared radiation has maximum at moderate energy flux, the heat absorption efficiency will first increase and then decrease with the incident energy flux. The local absorption efficiency will increase with the flow velocity, while the wall temperature drops quickly. Because of the unilateral concentrated solar radiation and different incident angle, the heat transfer is uneven along the circumference. Near the perpendicularly incident region, the wall temperature and absorption efficiency slowly approaches to the maximum, while the absorption efficiency sharply drops near the parallelly incident region. The calculation results show that the heat transfer parameters calculated from the average incident energy flux have a good agreement with the average values of the circumference under different boundary conditions. For the whole pipe with coating of Pyromark, the absorption efficiency of the main region is above 85%, and only the absorption efficiency near the parallelly incident region is below 80%. In general, the absorption efficiency of the whole pipe increases with flow velocity rising and pipe length decreasing, and it approaches to the maximum at optimal concentrated solar flux. (author)

Jianfeng, Lu; Jing, Ding [School of Engineering, Sun Yat-Sen University, Guangzhou 510006 (China); Jianping, Yang [Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education, South China University of Technology, Guangzhou 510640 (China)

2010-11-15T23:59:59.000Z

129

Near-Field Radiative Heat Transfer between Metamaterials coated with Silicon Carbide Film  

E-Print Network [OSTI]

In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC.By careful tuning of the optical properties of metamaterial it is possible to excite electrical and magnetic resonance for the metamaterial and surface phonon polaritons for SiC at different spectral regions, resulting in the enhanced heat transfer. The effect of the SiC film thickness at different vacuum gaps is investigated. Results obtained from this study will be beneficial for application of thin film coatings for energy harvesting.

Basu, Soumyadipta; Wang, Liping

2014-01-01T23:59:59.000Z

130

Time-dependent Radiation Transfer in the Internal Shock Model Scenario for Blazar Jets  

E-Print Network [OSTI]

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.

Manasvita Joshi; Markus Boettcher

2010-11-13T23:59:59.000Z

131

Monte Carlo solution methods in a moment-based scale-bridging algorithm for thermal radiative transfer problems: Comparison with Fleck and Cummings  

SciTech Connect (OSTI)

We have developed a moment-based scale-bridging algorithm for thermal radiative transfer problems. The algorithm takes the form of well-known nonlinear-diffusion acceleration which utilizes a low-order (LO) continuum problem to accelerate the solution of a high-order (HO) kinetic problem. The coupled nonlinear equations that form the LO problem are efficiently solved using a preconditioned Jacobian-free Newton-Krylov method. This work demonstrates the applicability of the scale-bridging algorithm with a Monte Carlo HO solver and reports the computational efficiency of the algorithm in comparison to the well-known Fleck-Cummings algorithm. (authors)

Park, H. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Densmore, J. D. [Bettis Atomic Power Laboratory, West Mifflin, PA 15122 (United States); Wollaber, A. B.; Knoll, D. A.; Rauenzahn, R. M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2013-07-01T23:59:59.000Z

132

Heat transfer between parallel plates: An approach based on the linearized Boltzmann equation for a binary mixture of rigid-sphere gases  

E-Print Network [OSTI]

Heat transfer between parallel plates: An approach based on the linearized Boltzmann equation a concise and particularly accurate solution of the heat-transfer problem for a binary gas mixture confined.1063/1.2511039 I. INTRODUCTION The heat-transfer problem within the context of rarefied gas dynamics has been

Siewert, Charles E.

133

Computational study of atmospheric transfer radiation on an equatorial tropical desert (La Tatacoa, Colombia)  

E-Print Network [OSTI]

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.

Delgado-Correal, Camilo; Castao, Gabriel

2012-01-01T23:59:59.000Z

134

Parametric analysis of radiative-convective heat transfer around a circular cylinder in a cross flow using the finite volume radiation solution method  

SciTech Connect (OSTI)

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.

Lee, K.H.; Lee, J.S.; Choi, M. [Seoul National Univ. (Korea, Republic of). Dept. of Mechanical Engineering

1996-02-09T23:59:59.000Z

135

Monte Carlo radiative transfer simulation for the near-ocean-surface high-resolution downwelling irradiance statistics  

E-Print Network [OSTI]

We present a numerical study of the near-surface underwater solar light statistics using the state-of-the-art Monte Carlo radiative transfer (RT) simulations in the coupled atmosphere-ocean system. Advanced variance-reduction ...

Xu, Zao

136

A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows  

E-Print Network [OSTI]

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...

Greendyke, Robert Brian

2012-06-07T23:59:59.000Z

137

A Monte Carlo synthetic-acceleration method for solving the thermal radiation diffusion equation  

SciTech Connect (OSTI)

We present a novel synthetic-acceleration-based Monte Carlo method for solving the equilibrium thermal radiation diffusion equation in three spatial dimensions. The algorithm performance is compared against traditional solution techniques using a Marshak benchmark problem and a more complex multiple material problem. Our results show that our Monte Carlo method is an effective solver for sparse matrix systems. For solutions converged to the same tolerance, it performs competitively with deterministic methods including preconditioned conjugate gradient and GMRES. We also discuss various aspects of preconditioning the method and its general applicability to broader classes of problems.

Evans, Thomas M., E-mail: evanstm@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States); Mosher, Scott W., E-mail: moshersw@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States); Slattery, Stuart R., E-mail: sslattery@wisc.edu [University of WisconsinMadison, 1500 Engineering Dr., Madison, WI 53716 (United States); Hamilton, Steven P., E-mail: hamiltonsp@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States)

2014-02-01T23:59:59.000Z

138

A Monte Carlo Synthetic-Acceleration Method for Solving the Thermal Radiation Diffusion Equation  

SciTech Connect (OSTI)

We present a novel synthetic-acceleration based Monte Carlo method for solving the equilibrium thermal radiation diusion equation in three dimensions. The algorithm performance is compared against traditional solution techniques using a Marshak benchmark problem and a more complex multiple material problem. Our results show that not only can our Monte Carlo method be an eective solver for sparse matrix systems, but also that it performs competitively with deterministic methods including preconditioned Conjugate Gradient while producing numerically identical results. We also discuss various aspects of preconditioning the method and its general applicability to broader classes of problems.

Evans, Thomas M [ORNL] [ORNL; Mosher, Scott W [ORNL] [ORNL; Slattery, Stuart [University of Wisconsin, Madison] [University of Wisconsin, Madison

2014-01-01T23:59:59.000Z

139

Klein-Gordon equation and Hawking radiation in the dyon black hole with a cosmic string  

E-Print Network [OSTI]

Charged massive scalar particles are considered in the gravitational and electromagnetic field produced by a dyonic black hole with a cosmic string along the axis of symmetry. Exact solutions of both angular and radial parts of the covariant Klein-Gordon equation in this background are obtained, and are given in terms of the confluent Heun functions. We emphasize the role of the presence of the cosmic string in these solutions. From the radial solution, we obtain the exact wave solutions near the exterior horizon of the black hole, and discuss the Hawking radiation spectrum and the energy flux.

Vieira, H S; Silva, G V

2015-01-01T23:59:59.000Z

140

POLARIZED LINE FORMATION IN MULTI-DIMENSIONAL MEDIA. IV. A FOURIER DECOMPOSITION TECHNIQUE TO FORMULATE THE TRANSFER EQUATION WITH ANGLE-DEPENDENT PARTIAL FREQUENCY REDISTRIBUTION  

SciTech Connect (OSTI)

To explain the linear polarization observed in spatially resolved structures in the solar atmosphere, the solution of polarized radiative transfer (RT) equation in multi-dimensional (multi-D) geometries is essential. For strong resonance lines, partial frequency redistribution (PRD) effects also become important. In a series of papers, we have been investigating the nature of Stokes profiles formed in multi-D media including PRD in line scattering. For numerical simplicity, so far we have restricted our attention to the particular case of PRD functions which are averaged over all the incident and scattered directions. In this paper, we formulate the polarized RT equation in multi-D media that takes into account the Hanle effect with angle-dependent PRD functions. We generalize here to the multi-D case the method for Fourier series expansion of angle-dependent PRD functions originally developed for RT in one-dimensional geometry. We show that the Stokes source vector S = (S{sub I} , S{sub Q} , S{sub U} ){sup T} and the Stokes vector I = (I, Q, U){sup T} can be expanded in terms of infinite sets of components S-tilde{sup (k)}, I-tilde{sup (k)}, respectively, k in [0, +{infinity}). We show that the components S-tilde{sup (k)} become independent of the azimuthal angle ({psi}) of the scattered ray, whereas the components I-tilde{sup (k)} remain dependent on {psi} due to the nature of RT in multi-D geometry. We also establish that S-tilde{sup (k)} and I-tilde{sup (k)} satisfy a simple transfer equation, which can be solved by any iterative method such as an approximate Lambda iteration or a Bi-Conjugate Gradient-type projection method provided we truncate the Fourier series to have a finite number of terms.

Anusha, L. S.; Nagendra, K. N. [Indian Institute of Astrophysics, Koramangala, 2nd Block, Bangalore 560 034 (India)

2011-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

PHYSICAL REVIEW B 85, 155422 (2012) Near-field thermal radiation transfer controlled by plasmons in graphene  

E-Print Network [OSTI]

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

Soljaèiæ, Marin

142

Eurotherm Seminar N81 Reactive Heat Transfer in Porous Media, Ecole des Mines d'Albi, France June 4-6, 2007 ET81-1 HEAT TRANSFER BY SIMULTANEOUS RADIATION-CONDUCTION  

E-Print Network [OSTI]

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

Boyer, Edmond

143

Investigation of Radiation and Chemical Resistance of Flexible HLW Transfer Hose  

SciTech Connect (OSTI)

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.

E. Skidmore; Billings, K.; Hubbard, M.

2010-03-24T23:59:59.000Z

144

On the transfer of energy towards infinity in the theory of weak turbulence for the nonlinear Schrdinger equation  

E-Print Network [OSTI]

We study the mathematical properties of a kinetic equation which describes the long time behaviour of solutions to the weak turbulence equation associated to the cubic nonlinear Schr\\"odinger equation. In particular, we give a precise definition of weak solutions and prove global existence of solutions for all initial data with finite mass. We also prove that any nontrivial initial datum yields the instantaneous onset of a condensate, i.e. a Dirac mass at the origin for any positive time. Furthermore we show that the only stationary solutions with finite total measure are Dirac masses at the origin. We finally construct solutions with finite energy, which is transferred to infinity in a self-similar manner.

A. H. M. Kierkels; J. J. L. Velzquez

2014-10-08T23:59:59.000Z

145

Milagro Version 2 An Implicit Monte Carlo Code for Thermal Radiative Transfer: Capabilities, Development, and Usage  

SciTech Connect (OSTI)

We have released Version 2 of Milagro, an object-oriented, C++ code that performs radiative transfer using Fleck and Cummings' Implicit Monte Carlo method. Milagro, a part of the Jayenne program, is a stand-alone driver code used as a methods research vehicle and to verify its underlying classes. These underlying classes are used to construct Implicit Monte Carlo packages for external customers. Milagro-2 represents a design overhaul that allows better parallelism and extensibility. New features in Milagro-2 include verified momentum deposition, restart capability, graphics capability, exact energy conservation, and improved load balancing and parallel efficiency. A users' guide also describes how to configure, make, and run Milagro2.

T.J. Urbatsch; T.M. Evans

2006-02-15T23:59:59.000Z

146

Radiative heat transfer between two dielectric nanogratings in the scattering approach  

E-Print Network [OSTI]

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.

J. Lussange; R. Gurout; F. S. S. Rosa; J. -J. Greffet; A. Lambrecht; S. Reynaud

2012-06-01T23:59:59.000Z

147

A 3D radiative transfer framework: I. non-local operator splitting and continuum scattering problems  

E-Print Network [OSTI]

We describe a highly flexible framework to solve 3D radiation transfer problems in scattering dominated environments based on a long characteristics piece-wise parabolic formal solution and an operator splitting method. We find that the linear systems are efficiently solved with iterative solvers such as Gauss-Seidel and Jordan techniques. We use a sphere-in-a-box test model to compare the 3D results to 1D solutions in order to assess the accuracy of the method. We have implemented the method for static media, however, it can be used to solve problems in the Eulerian-frame for media with low velocity fields.

Peter H. Hauschildt; E. Baron

2006-01-09T23:59:59.000Z

148

RADIATION HEAT TRANSFER ENVIRONMENT IN FIRE AND FURNACE TESTS OF RADIOACTIVE MATERIALS PAKCAGES  

SciTech Connect (OSTI)

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.

Smith, A

2008-12-31T23:59:59.000Z

149

Radiation Modeling In Fluid Flow Iain D. Boyd  

E-Print Network [OSTI]

· Closing remarks #12;3 Radiation In Fluid Flows · Radiation transport is an important phenomenon in many 5800 K #12;7 Fundamentals of Radiation Transport · Radiation does not require a medium !!! dI (s, ! ) ds +(p +g )I (s, ! )+ p I (s, ! ) Radiative Transfer Equation (RTE) - spectral intensity

Wang, Wei

150

Nonadiabatic electron transfer in the condensed phase, via semiclassical and Langevin equation approach  

E-Print Network [OSTI]

In this dissertation, we discuss two methods developed during my PhD study to simulate electron transfer systems. The first method, the semi-classical approximation, is derived from the stationary phase approximation to ...

Song, XiaoGeng, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

151

Hybrid Characteristics: 3D radiative transfer for parallel adaptive mesh refinement hydrodynamics  

E-Print Network [OSTI]

We have developed a three-dimensional radiative transfer method designed specifically for use with parallel adaptive mesh refinement hydrodynamics codes. This new algorithm, which we call hybrid characteristics, introduces a novel form of ray tracing that can neither be classified as long, nor as short characteristics, but which applies the underlying principles, i.e. efficient execution through interpolation and parallelizability, of both. Primary applications of the hybrid characteristics method are radiation hydrodynamics problems that take into account the effects of photoionization and heating due to point sources of radiation. The method is implemented in the hydrodynamics package FLASH. The ionization, heating, and cooling processes are modelled using the DORIC ionization package. Upon comparison with the long characteristics method, we find that our method calculates the column density with a similarly high accuracy and produces sharp and well defined shadows. We show the quality of the new algorithm in an application to the photoevaporation of multiple over-dense clumps. We present several test problems demonstrating the feasibility of our method for performing high resolution three-dimensional radiation hydrodynamics calculations that span a large range of scales. Initial performance tests show that the ray tracing part of our method takes less time to execute than other parts of the calculation (e.g. hydrodynamics and adaptive mesh refinement), and that a high degree of efficiency is obtained in parallel execution. Although the hybrid characteristics method is developed for problems involving photoionization due to point sources, the algorithm can be easily adapted to the case of more general radiation fields.

Erik-Jan Rijkhorst; Tomasz Plewa; Anshu Dubey; Garrelt Mellema

2005-05-10T23:59:59.000Z

152

On Existence of $L^1$-solutions for Coupled Boltzmann Transport Equation and Radiation Therapy Treatment Optimization  

E-Print Network [OSTI]

The paper considers a linear system of Boltzmann transport equations modelling the evolution of three species of particles, photons, electrons and positrons. The system is coupled because of the collision term (an integral operator). The model is intended especially for dose calculation (forward problem) in radiation therapy. We show under physically relevant assumptions that the system has a unique solution in appropriate ($L^1$-based) spaces and that the solution is non-negative when the data (internal source and inflow boundary source) is non-negative. In order to be self-contained as much as is practically possible, many (basic) results and proofs have been reproduced in the paper. Existence, uniqueness and non-negativity of solutions for the related time-dependent coupled system are also proven. Moreover, we deal with inverse radiation treatment planning problem (inverse problem) as an optimal control problem both for external and internal therapy (in general $L^p$-spaces). Especially, in the case $p=2$ ...

Tervo, Jouko

2014-01-01T23:59:59.000Z

153

Schur-decomposition for 3D matrix equations and its application in solving radiative discrete ordinates equations discretized by Chebyshev collocation spectral method  

SciTech Connect (OSTI)

The Schur-decomposition for three-dimensional matrix equations is developed and used to directly solve the radiative discrete ordinates equations which are discretized by Chebyshev collocation spectral method. Three methods, say, the spectral methods based on 2D and 3D matrix equation solvers individually, and the standard discrete ordinates method, are presented. The numerical results show the good accuracy of spectral method based on direct solvers. The CPU time cost comparisons against the resolutions between these three methods are made using MATLAB and FORTRAN 95 computer languages separately. The results show that the CPU time cost of Chebyshev collocation spectral method with 3D Schur-decomposition solver is the least, and almost only one thirtieth to one fiftieth CPU time is needed when using the spectral method with 3D Schur-decomposition solver compared with the standard discrete ordinates method.

Li Benwen [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, P.O. Box 314, Shenyang, Liaoning 110004 (China)], E-mail: heatli@hotmail.com; Tian Shuai; Sun Yasong; Hu, Zhang-Mao [Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, P.O. Box 314, Shenyang, Liaoning 110004 (China)

2010-02-20T23:59:59.000Z

154

Self-averaging in time reversal for the parabolic wave equation Guillaume Bal George Papanicolaou y Leonid Ryzhik z  

E-Print Network [OSTI]

is the solution of a transport equation. 1 Introduction In time-reversal experiments a signal emitted, in the regimes of random geometrical optics and radiative transfer (transport), was studied in [2, 3]. We also in the radiative transfer regime using the parabolic wave equation, when the waves interact fully with the random

Bal, Guillaume

155

Proceedings of the 8 International Symposium on Heat Transfer  

E-Print Network [OSTI]

, contributions from radiation can be determined via solution of the Equation of Radiative Transfer (ERT equation can lead to significant error, due to the short time-duration of the transport processes, Beijing, China ISHT8-07-05 MODELING OF ULTRAFAST LASER TRANSPORT AND APPLICATIONS Zhixiong Guo Rutgers

Guo, Zhixiong "James"

156

PARALLEL COMPUTATION OF THE BOLTZMANN TRANSPORT EQUATION FOR MICROSCALE HEAT  

E-Print Network [OSTI]

silicon ðSi? and silicon dioxide ðSiO2?. The equation of phonon radiative transport ðERPT?, in itsPARALLEL COMPUTATION OF THE BOLTZMANN TRANSPORT EQUATION FOR MICROSCALE HEAT TRANSFER fundamental Boltzmann transport equations have been reported [3, 7, 8]. This has consequently instigated a re

Miller, Richard S.

157

Hyperspectral Aquatic Radiative Transfer Modeling Using a High-Performance Cluster Computing-Based Approach  

SciTech Connect (OSTI)

Abstract For aquatic studies, radiative transfer (RT) modeling can be used to compute hyperspectral above-surface remote sensing reflectance that can be utilized for inverse model development. Inverse models can provide bathymetry and inherent-and bottom-optical property estimation. Because measured oceanic field/organic datasets are often spatio-temporally sparse, synthetic data generation is useful in yielding sufficiently large datasets for inversion model development; however, these forward-modeled data are computationally expensive and time-consuming to generate. This study establishes the magnitude of wall-clock-time savings achieved for performing large, aquatic RT batch-runs using parallel computing versus a sequential approach. Given 2,600 simulations and identical compute-node characteristics, sequential architecture required ~100 hours until termination, whereas a parallel approach required only ~2.5 hours (42 compute nodes) a 40x speed-up. Tools developed for this parallel execution are discussed.

Filippi, Anthony M [ORNL; Bhaduri, Budhendra L [ORNL; Naughton, III, Thomas J [ORNL; King, Amy L [ORNL; Scott, Stephen L [ORNL; Guneralp, Inci [Texas A& M University

2012-01-01T23:59:59.000Z

158

Hyperspectral Aquatic Radiative Transfer Modeling Using a High-Performance Cluster Computing Based Approach  

SciTech Connect (OSTI)

For aquatic studies, radiative transfer (RT) modeling can be used to compute hyperspectral above-surface remote sensing reflectance that can be utilized for inverse model development. Inverse models can provide bathymetry and inherent- and bottom-optical property estimation. Because measured oceanic field/organic datasets are often spatio-temporally sparse, synthetic data generation is useful in yielding sufficiently large datasets for inversion model development; however, these forward-modeled data are computationally expensive and time-consuming to generate. This study establishes the magnitude of wall-clock-time savings achieved for performing large, aquatic RT batch-runs using parallel computing versus a sequential approach. Given 2,600 simulations and identical compute-node characteristics, sequential architecture required {approx}100 hours until termination, whereas a parallel approach required only {approx}2.5 hours (42 compute nodes) - a 40x speed-up. Tools developed for this parallel execution are discussed.

Fillippi, Anthony [Texas A& M University; Bhaduri, Budhendra L [ORNL; Naughton, III, Thomas J [ORNL; King, Amy L [ORNL; Scott, Stephen L [ORNL; Guneralp, Inci [Texas A& M University

2012-01-01T23:59:59.000Z

159

High-performance solution of hierarchical equations of motions for studying energy-transfer in light-harvesting complexes  

E-Print Network [OSTI]

Excitonic models of light-harvesting complexes, where the vibrational degrees of freedom are treated as a bath, are commonly used to describe the motion of the electronic excitation through a molecule. Recent experiments point toward the possibility of memory effects in this process and require to consider time non-local propagation techniques. The hierarchical equations of motion (HEOM) were proposed by Ishizaki and Fleming to describe the site-dependent reorganization dynamics of protein environments (J. Chem. Phys., 130, p. 234111, 2009), which plays a significant role in photosynthetic electronic energy transfer. HEOM are often used as a reference for other approximate methods, but have been implemented only for small systems due to their adverse computational scaling with the system size. Here, we show that HEOM are also solvable for larger systems, since the underlying algorithm is ideally suited for the usage of graphics processing units (GPU). The tremendous reduction in computational time due to the GPU allows us to perform a systematic study of the energy-transfer efficiency in the Fenna-Matthews-Olson (FMO) light-harvesting complex at physiological temperature under full consideration of memory-effects. We find that approximative methods differ qualitatively and quantitatively from the HEOM results and discuss the importance of finite temperature to achieve high energy-transfer efficiencies.

Christoph Kreisbeck; Tobias Kramer; Mirta Rodriguez; Birgit Hein

2011-05-25T23:59:59.000Z

160

An Analytical Model of Radiation-Induced Charge Transfer Inefficiency for CCD Detectors  

E-Print Network [OSTI]

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...

Short, Alexander; de Bruijne, Jos H J; Prod'homme, Thibaut

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Solutions of the equation of radiative transfer by matrix operator techniques  

E-Print Network [OSTI]

for Rayleigh Scattering for us = 1 and Various Values of the Optical Thickness r as a Function of the Cosine of the Nadir Angle u. . . . . . . . . . . . . . . . . . . . . . . . 25 3. Upward Radiance at Top of the Atmosphere for Haze M Scattering for uc = 1... with a given radius is proportional to r exp(-8. 944 r '), where r is the particle radius. The mode radius or size of maximum frequency in the distribution is 0. 05 p. The single scattering phase function is calculated assuming a wavelength of 0. 75 u...

Catchings, Frances Eugenia King

1973-01-01T23:59:59.000Z

162

Spectrally enhancing near-field radiative heat transfer by exciting magnetic polariton in SiC gratings  

E-Print Network [OSTI]

In the present work, we theoretically demonstrate, for the first time, that near field radiative transport between 1D periodic grating microstructures separated by subwavelength vacuum gaps can be significantly enhanced by exciting magnetic resonance or polariton. Fluctuational electrodynamics that incorporates scattering matrix theory with rigorous coupled wave analysis is employed to exactly calculate the near field radiative heat flux between two SiC gratings. Besides the well known coupled surface phonon polaritons (SPhP), an additional spectral radiative heat flux peak, which is due to magnetic polariton, is found within the phonon absorption band of SiC. The mechanisms, behaviors and interplays between magnetic polariton, coupled SPhP, single interface SPhP, and Wood's anomaly in the near field radiative transport are elucidated in detail. The findings will open up a new way to control near field radiative heat transfer by magnetic resonance with micro or nanostructured metamaterials.

Yang, Yue

2015-01-01T23:59:59.000Z

163

The convergence of an explicit finite difference solution for transient heat transfer in solids with radiation at one boundary  

E-Print Network [OSTI]

at the Interior Point 'n ' 17 8 ? 01 Temperature Resp C 2'( C 1, Wi Constant Tempera x = L, and Havin Transfer to a He Degree Absolute Calculated With Modulus as Per S at x/L = 0. 0 onse th a ture g Ra at S Temp a Mr tabi of Hea at dian ink.... The Fourier equation for one? dimensional heat conduction in solids with constant physical properties is BT K 0 T Qe gC Q~x (3 ? 01) The net radiant heat transfer rate between two gray bodies A and B at absolute temperature T and T will be B according...

Patel, Bhagubhai Desaibhai

2012-06-07T23:59:59.000Z

164

HELIOS-K: An Ultrafast, Open-source Opacity Calculator for Radiative Transfer  

E-Print Network [OSTI]

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...

Grimm, Simon L

2015-01-01T23:59:59.000Z

165

The evolved circumbinary disk of AC Her: a radiative transfer, interferometric and mineralogical study  

E-Print Network [OSTI]

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 ...

Hillen, M; Menu, J; Van Winckel, H; Min, M; Mulders, G D

2015-01-01T23:59:59.000Z

166

Modeling near-field radiative heat transfer from sharp objects using a general 3d numerical scattering technique  

E-Print Network [OSTI]

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.

McCauley, Alexander P; Krger, Matthias; Johnson, Steven G

2011-01-01T23:59:59.000Z

167

On a Generalized Boltzmann Equation for Non-Classical Particle Transport  

E-Print Network [OSTI]

equations. Diffusion asymptotics. Radiative transfer. Neutron transport. AMS Subject classification. 35Q99On a Generalized Boltzmann Equation for Non-Classical Particle Transport Martin Frank1 and Thierry of collisional transport equations is broken by the introduction of the memory terms. Key words. Transport

Goudon, Thierry

168

Normal shock solutions to the viscous shock layer equations including thermal, chemical, thermodynamic, and radiative nonequilibrium  

E-Print Network [OSTI]

An existing axisymmetric body viscous shock layer code including chemical, thermal, and thermodynamic nonequilibrium and nonequilibrium radiative gasdynamic coupling is adapted to simulate the one-dimensional flow within a shock tube. A suitable...

Mott, David Ray

1993-01-01T23:59:59.000Z

169

E-Print Network 3.0 - alpha radiative transfer Sample Search...  

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

Radiological Research Accelerator Facility Collection: Biology and Medicine ; Fission and Nuclear Technologies 43 Radiation Protection Dosimetry Vol. 97, No. 3, pp. 279-285 (2001)...

170

E-Print Network 3.0 - atmospheric radiative transfer Sample Search...  

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

Earth and Atmospheric Sciences, Cornell University Collection: Geosciences 49 The Greenhouse Effect without Feedbacks Summary: Number microns10.016.7 7.14 T261K 12;Radiative...

171

Radiative transfer within non Beerian porous media with semitransparent and opaque phases in non equilibrium;  

E-Print Network [OSTI]

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

Boyer, Edmond

172

To be submitted to ApJ A Formalism for Covariant Polarized Radiative Transport by Ray  

E-Print Network [OSTI]

To be submitted to ApJ A Formalism for Covariant Polarized Radiative Transport by Ray Tracing that the transport equation in vacuo is kµ µN = 0. We show that this is equivalent to Broderick & Blandford (2004)'s a procedure for solving the polarized radiative transfer equation in a curved spacetime. Other possible

Gammie, Charles F.

173

Radiative transfer based scaling of LAI retrievals from reflectance data of different resolutions  

E-Print Network [OSTI]

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

Myneni, Ranga B.

174

Characterization of the solar light field within the ocean mesopelagic zone based on radiative transfer simulations  

E-Print Network [OSTI]

Characterization of the solar light field within the ocean mesopelagic zone based on radiative t The solar light field within the ocean from the sea surface to the bottom of the mesopelagic zone there is sufficient amount of solar light to support the process of photosynthesis, and below by the aphotic

Stramski, Dariusz

175

Simulation of Infrared Laser Heating of Silica Using Heat Conduction and Multifrequency Radiation Diffusion Equations Adapted for Homogeneous Refractive Lossy Media  

SciTech Connect (OSTI)

Localized, transient heating of materials using micro-scale, highly absorbing laser light has been used in many industries to anneal, melt and ablate material with high precision. Accurate modeling of the relative contributions of conductive, convective and radiative losses as a function of laser parameters is essential to optimizing micro-scale laser processing of materials. In bulk semi-transparent materials such as silicate glass melts, radiation transport is known to play a significantly larger role as the temperature increases. Conventionally, radiation is treated in the frequency-averaged diffusive limit (Rosseland approximation). However, the role and proper treatment of radiative processes under rapidly heated, high thermal gradient conditions, often created through laser-matter interactions, is at present not clear. Starting from the radiation transport equation for homogeneous, refractive lossy media, they derive the corresponding time-dependent multi-frequency diffusion equations. Zeroth and first moments of the transport equation couple the energy density, flux and pressure tensor. The system is closed by neglecting the temporal derivative of the flux and replacing the pressure tensor by its diagonal analogue. The radiation equations are coupled to a diffusion equation for the matter temperature. They are interested in modeling infrared laser heating of silica over sub-millimeter length scales, and at possibly rapid rates. Hence, in contrast to related work, they retain the temporal derivative of the radiation field. They derive boundary conditions at a planar air-silica interface taking account of reflectivities obtained from the Fresnel relations that include absorption. The effect of a temperature-dependent absorption index is explored through construction of a multi-phonon dielectric function that includes mode dispersion. The spectral dimension is discretized into a finite number of intervals yielding a system of multigroup diffusion equations. Simulations are presented. To demonstrate the bulk heat loss due to radiation and the effect of the radiation's temporal derivative, they model cooling of a silica slab, initially at 2500 K, for 10 s. Retaining the derivative enables correctly modeling the loss of photons initially present in the slab. Other simulations model irradiating silica discs (of approximately 5 mm radii and thickness) with a CO2 laser: {lambda} = 10.59 and 4.6 um, Gaussian profile, r{sub 0} = 0.5 mm for 1/e decay. By surrounding the disks in room-temperature air, they make use of the boundary conditions described above.

Shestakov, A I; Matthews, M J; Vignes, R M; Stolken, J S

2010-10-28T23:59:59.000Z

176

A novel approach for introducing cloud spatial structure into cloud radiative transfer parameterizations  

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

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.

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

177

A CLASS OF PHYSICALLY MOTIVATED CLOSURES FOR RADIATION HYDRODYNAMICS  

SciTech Connect (OSTI)

Radiative transfer and radiation hydrodynamics use the relativistic Boltzmann equation to describe the kinetics of photons. It is difficult to solve the six-dimensional time-dependent transfer equation unless the problem is highly symmetric or in equilibrium. When the radiation field is smooth, it is natural to take angular moments of the transfer equation to reduce the degrees of freedom. However, low order moment equations contain terms that depend on higher order moments. To close the system of moment equations, approximations are made to truncate this hierarchy. Popular closures used in astrophysics include flux-limited diffusion and the M{sub 1} closure, which are rather ad hoc and do not necessarily capture the correct physics. In this paper, we propose a new class of closures for radiative transfer and radiation hydrodynamics. We start from a different perspective and highlight the consistency of a fully relativistic formalism. We present a generic framework to approximate radiative transfer based on relativistic Grad's moment method. We then derive a 14-field method that minimizes unphysical photon self-interaction.

Chan, Chi-kwan, E-mail: ckchan@cfa.harvard.edu [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2011-02-01T23:59:59.000Z

178

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

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500II FieldVacancy-InducedCloudPoisson Stochastic Radiative

179

Astrophysical S factor for the radiative capture (12)N(p,gamma)(13)O determined from the (14)N((12)N,(13)O)(13)C proton transfer reaction  

E-Print Network [OSTI]

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...

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

180

Frequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs: A Computational Approach for Arbitrary Geometries and Materials  

E-Print Network [OSTI]

of energy from a hot to a cold body is well known to be enhanced (even exceeding the black- body limit) whenFrequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 3 Department

Soljaèiæ, Marin

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

A High-Order-Accurate GPU-Based Radiative Transfer Equation Solver for Combustion and Propulsion Applications  

E-Print Network [OSTI]

results for the 3D combustor shown in Figure 5 with thoseback walls of a 3D combustor chamber [46] with absorbing,and (b) ? = 0.5 of the 3D combustor. Discrepancies in flux

He, Xing; Lee, Euntaek; Wilcox, Lucas; Munipalli, Ramakanth; Pilon, Laurent

2013-01-01T23:59:59.000Z

182

Proceedings of the 7th International Symposium on Radiative Transfer, RAD-13 June 28, 2013, Kuadasi, Turkey  

E-Print Network [OSTI]

, Kuadasi, Turkey RAD-13-040 SPECTRAL RADIATIVE PROPERTIES OF THREE-DIMENSIONALLY ORDERED MACROPOROUS CERIA

183

Phase retrieval using radiation and matter-wave fields: Validity of Teague's method for solution of the transport-of-intensity equation  

SciTech Connect (OSTI)

Although originally developed for coherent paraxial scalar electromagnetic radiation in the visible-light regime, phase retrieval using the transport-of-intensity equation has been successfully applied to a range of paraxial radiation and matter-wave fields. Such applications include using electron wave fields to quantitatively image magnetic skyrmions and spin ices, propagation-based phase-contrast imaging using cold neutrons and hard x-rays, and visible-light refractive imaging of the projected column density of cold-atom clouds. Teague's method for phase retrieval using the transport-of-intensity equation, which renders the phase of a paraxial complex wave indirectly measurable via the existence of a conserved current, has been applied to a broad variety of situations which include all of the experiments described above. However, these applications have been undertaken without a thorough analysis of the underlying validity of the method. Here we derive sufficient conditions for the phase-retrieval solution provided by Teague's method to coincide with the true phase of the paraxial radiation or matter-wave field. We also present a sufficient condition guaranteeing that the discrepancy between the true phase function and that reconstructed using Teague's solution is small. These conditions demonstrate that, in most practical cases, for phase-amplitude retrieval using the transport-of-intensity equation, the Teague solution is very close to the exact solution. However, we also describe a counter example in the context of phase-amplitude retrieval using hard x-rays, in which the relative root-mean-square difference between the exact solution and that obtained using Teague's method is 9%. These findings clarify the foundations of one of the most widely applied methods for propagation-based phase retrieval of both paraxial matter and radiation wave fields and define a region for its applicability.

Schmalz, Jelena A. [School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); Gureyev, Timur E. [CSIRO Materials Science and Engineering, PB 33, Clayton South MDC, VIC 3169 (Australia); School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); Paganin, David M. [School of Physics, Monash University, VIC 3800 (Australia); Pavlov, Konstantin M. [School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); School of Physics, Monash University, VIC 3800 (Australia)

2011-08-15T23:59:59.000Z

184

Radiator Labs | Department of Energy  

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

of steam buildings. Radiator Labs developed a mechanism that allows heating systems to control heat transfer at each radiator. The Radiator Labs design utilizes an...

185

HYDRODYNAMIC AND RADIATIVE MODELING OF TEMPORAL H{alpha} EMISSION V/R VARIATIONS CAUSED BY DISCONTINUOUS MASS TRANSFER IN BINARIES  

SciTech Connect (OSTI)

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.

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

186

Evaluation of Radiometric Measurements from the NASA Multiangle Imaging Spectroradiometer (MISR): Two- and Three-Dimensional Radiative Transfer Modeling of an Inhomogeneous Stratocumulus Cloud Deck  

SciTech Connect (OSTI)

In December 1999, NASA launched the Terra satellite. This platform carries five instruments that measure important properties of the Earth climate system. One of these instruments is the Multiangle Imaging Spectroradiometer, or MISR. This instrument measures light reflected from the Earth at a spatial resolution of 275-1100 m, at four wavelengths (446, 558, 672, and 866 nm), and at nine different viewing angles that vary from +70 to -70 degrees along the direction of flight [Diner et al., 2002]. These multiangle data have the potential to provide information on aerosols, surface, and cloud characteristics that compliments traditional single-view-direction satellite measurements. Before this potential can be realized, the accuracy of the satellite radiance measurements must be carefully assessed, and the implications of the radiometric accuracy on remote-sensing algorithms must be evaluated. In this article, we compare MISR multiangle measurements against two-dimensional (2-D) and 3-D radiative transfer calculations from an inhomogeneous cloud scene. Inputs to the radiative transfer code are based entirely on independently gathered data (ground-based radar, lidar, microwave radiometer, in situ aircraft data, etc.). The 2-D radiative transfer calculations compare favorably near nadir and in most of the forward scattering directions, but differ by as much as 10% in the backscattering directions. Using 3-D radiative transfer modeling, we show that this difference is due to the 3-D structure of the cloud deck, including variations in the cloud top height on scales less than 275 m, which are not resolved in the 2-D simulations. Comparison of the 2-D calculations to the MISR measurements, after accounting for the 3-D structure, show residual differences that are less than 4% at all angles at the MISR blue and green wavelengths. The comparison also reveals that the MISR measurements at the red and near-infrared wavelengths are too bright relative to measurements in the blue and green bands. On the basis of the results of this study, along with results from five other comparisons, the MISR calibration is being adjusted to reduce the red and nearinfrared Radiances.

Marchand, Roger T.; Ackerman, Thomas P.

2004-09-29T23:59:59.000Z

187

A WRF Simulation of the Impact of 3-D Radiative Transfer on Surface Hydrology over the Rocky Mountains and Sierra Nevada  

SciTech Connect (OSTI)

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.

Liou, K. N.; Gu, Y.; Leung, Lai-Yung R.; Lee, W- L.; Fovell, R. G.

2013-12-03T23:59:59.000Z

188

Electron-Transfer from H-2 and Ar to Stored Multiply Charged Argon Ions Produced by Synchrotron Radiation  

E-Print Network [OSTI]

for collisions of He and Ne with doubly charged ions of the lanthanide series, La +, Ce +, etc. , the ionization poten- tials of multiply charged ions greatly exceed those of atoms or molecules with which they collide, so electron transfer from the neutral...

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

189

Anisotropic radiation elds: causality and quantum statistics  

E-Print Network [OSTI]

radiation transport 5 2.1 Radiation transport equation . . . . . . . . . . . . . . . . . . 5 2.2 Closures The transport of radiation through a medium is described by the radiation transport equation for the radiative is used to describe anisotropic radiation. Because the two moment equations do not form a closed set

Honingh, Aline

190

Proceedings of the 7th International Symposium on Radiative Transfer, RAD-13 June 2-8, 2013, Kuadasi, Turkey  

E-Print Network [OSTI]

of external irradiation, and thus needs to be examined by the comparison with the direct Monte Carlo simulation. The computational study with realistic geometrical and optical parameters of the problem nanoshells G irradiation J diffuse component of radiation intensity m complex index of refraction, n - i n

191

Numerical treatment of the hyperboloidal initial value problem for the vacuum Einstein equations. III. On the determination of radiation  

E-Print Network [OSTI]

We discuss the issue of radiation extraction in asymptotically flat space-times within the framework of conformal methods for numerical relativity. Our aim is to show that there exists a well defined and accurate extraction procedure which mimics the physical measurement process. It operates entirely intrisically within $\\scri^+$ so that there is no further approximation necessary apart from the basic assumption that the arena be an asymptotically flat space-time. We define the notion of a detector at infinity by idealising local observers in Minkowski space. A detailed discussion is presented for Maxwell fields and the generalisation to linearised and full gravity is performed by way of the similar structure of the asymptotic fields.

J. Frauendiener

1998-08-26T23:59:59.000Z

192

Induction and Persistence of Large ?H2AX Foci by High Linear Energy Transfer Radiation in DNA-Dependent protein kinaseDeficient Cells  

SciTech Connect (OSTI)

Purpose: To evaluate the cell response to DNA double-strand breaks induced by low and high linear energy transfer (LET) radiations when the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), an essential protein of the nonhomologous end-joining repair pathway, lacks kinase activity. Methods and Materials: CHO10B2, a Chinese hamster ovary cell line, and its derived radiosensitive mutant cell line, irs-20, lacking DNA-PKcs activity, were evaluated after 0 to 3 Gy of ?-rays, plateau and Bragg peak protons, and lithium beams by clonogenic assay, and as a measurement of double-strand breaks, phosphorylated H2AX (?H2AX) foci number and size were quantified by immunocytofluorescence. Results: Irs-20 exhibited greater radiosensitivity and a higher amount of ?H2AX foci than CHO10B2 at 6 hours after irradiation for all types of radiations. Remarkably, CHO10B2 and irs-20 maintained their difference in radiosensitivity after high-LET radiation. Six hours after low-LET radiations, irs-20 did not reach basal levels of ?H2AX at high doses, whereas CHO10B2 recovered basal levels for all doses. After high-LET radiation, only CHO10B2 exhibited a reduction in ?H2AX foci, but it never reached basal levels. Persistent foci in irs-20 confirmed a repair deficiency. Interestingly, after 30 minutes of high-LET radiation both cell lines exhibited large foci (size >0.9 ?m{sup 2}) related to the damage nature, whereas at 6 hours irs-20 showed a higher amount of large foci than CHO10B2, with a 7-fold increase at 3 Gy, that could also be associated to radiosensitivity. Conclusions: We demonstrated, for the first time, an association between deficient DNA-PKcs activity and not only high levels of H2AX phosphorylation but also persistence and size increase of ?H2AX foci after high-LET irradiation.

Bracalente, Candelaria; Ibaez, Irene L. [Departamento de Micro y Nanotecnologa, Comisin Nacional de Energa Atmica, San Martn, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientficas y Tcnicas, Buenos Aires (Argentina); Molinari, Beatriz [Departamento de Radiobiologa, Comisin Nacional de Energa Atmica, San Martn, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientficas y Tcnicas, Buenos Aires (Argentina); Palmieri, Mnica [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires (Argentina); Kreiner, Andrs [Consejo Nacional de Investigaciones Cientficas y Tcnicas, Buenos Aires (Argentina); Gerencia de Investigacin y Aplicaciones, Comisin Nacional de Energa Atmica, San Martn, Buenos Aires (Argentina); Escuela de Ciencia y Tecnologa, Universidad Nacional de San Martn, San Martn, Buenos Aires (Argentina); Valda, Alejandro [Escuela de Ciencia y Tecnologa, Universidad Nacional de San Martn, San Martn, Buenos Aires (Argentina); and others

2013-11-15T23:59:59.000Z

193

A Green's function formalism of energy and momentum transfer in fluctuational electrodynamics  

E-Print Network [OSTI]

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.

Arvind Narayanaswamy; Yi Zheng

2013-02-03T23:59:59.000Z

194

Coupled forward-adjoint monte carlo simulations of radiative transport for the study of optical probe design in heterogeneous tissues  

E-Print Network [OSTI]

approximation to the radiative transport equation [3, 7, 15,form of the radiative transport equation (RTE) assumed to

Hayakawa, Carole K.; Spanier, Jerome; Venugopalan, Vasan

2007-01-01T23:59:59.000Z

195

On the influence of the companion star in Eta Carinae: 2D radiative transfer modeling of the ultraviolet and optical spectra  

E-Print Network [OSTI]

We present 2D radiative transfer modeling of the Eta Carinae binary system accounting for the presence of a wind-wind collision (WWC) cavity carved in the optically-thick wind of the primary star. By comparing synthetic line profiles with HST/STIS spectra obtained near apastron, we show that the WWC cavity has a strong influence on multi-wavelength diagnostics. This influence is regulated by the modification of the optical depth in the continuum and spectral lines. We find that H-alpha, H-beta, and Fe II lines are the most affected by the WWC cavity, since they form over a large volume of the primary wind. These spectral lines depend on latitude and azimuth since, according to the orientation of the cavity, different velocity regions of a spectral line are affected. For 2D models with orientation corresponding to orbital inclination angle 110deg < i < 140deg and longitude of periastron 210deg < omega < 330deg, the blueshifted and zero-velocity regions of the line profiles are the most affected. Th...

Groh, Jose H; Madura, Thomas I; Weigelt, Gerd

2012-01-01T23:59:59.000Z

196

5. Heat transfer Ron Zevenhoven  

E-Print Network [OSTI]

1/120 5. Heat transfer Ron Zevenhoven ?bo Akademi University Thermal and Flow Engineering / Värme Three heat transfer mechanisms Conduction Convection Radiation 2/120 Pic: B?88 ?bo Akademi University | Thermal and Flow Engineering | 20500 Turku | Finland #12;3/120 5.1 Conductive heat transfer ?bo Akademi

Zevenhoven, Ron

197

Generalized linear Boltzmann equations for particle transport in polycrystals  

E-Print Network [OSTI]

The linear Boltzmann equation describes the macroscopic transport of a gas of non-interacting point particles in low-density matter. It has wide-ranging applications, including neutron transport, radiative transfer, semiconductors and ocean wave scattering. Recent research shows that the equation fails in highly-correlated media, where the distribution of free path lengths is non-exponential. We investigate this phenomenon in the case of polycrystals whose typical grain size is comparable to the mean free path length. Our principal result is a new generalized linear Boltzmann equation that captures the long-range memory effects in this setting. A key feature is that the distribution of free path lengths has an exponential decay rate, as opposed to a power-law distribution observed in a single crystal.

Jens Marklof; Andreas Strmbergsson

2015-02-13T23:59:59.000Z

198

Power transfer through strongly coupled resonances  

E-Print Network [OSTI]

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 ...

Kurs, Andr

2007-01-01T23:59:59.000Z

199

Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference July 19-23, 2009, San Francisco, CA, USA HT2009-88261 SIMULATION OF FOCUSED RADIATION PROPAGATION AND TRANSIENT HEAT TRANSFER IN TURBID-dependent radiation and conduction bio-heat transfer model. Ultrashort pulsed radiation transport in the cylindrical

Guo, Zhixiong "James"

200

astroph/9507030 Gravitational Radiation  

E-Print Network [OSTI]

astro­ph/9507030 10 Jul 95 Gravitational Radiation and Very Long Baseline Interferometry Ted Pyne of gravitational radiation on astrometric observations. We derive an equation for the time delay measured by two antennae observing the same source in an Einstein­de Sitter spacetime containing gravitational radiation

Fygenson, Deborah Kuchnir

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Radiator Labs | Department of Energy  

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

distribution system via a network of pipes and radiators. There is no way to control heat transfer through this network, so building managers configure boiler systems to treat...

202

Modeling Granular Materials as Compressible Non-Linear Fluids: Heat Transfer Boundary Value Problems  

SciTech Connect (OSTI)

We discuss three boundary value problems in the flow and heat transfer analysis in flowing granular materials: (i) the flow down an inclined plane with radiation effects at the free surface; (ii) the natural convection flow between two heated vertical walls; (iii) the shearing motion between two horizontal flat plates with heat conduction. It is assumed that the material behaves like a continuum, similar to a compressible nonlinear fluid where the effects of density gradients are incorporated in the stress tensor. For a fully developed flow the equations are simplified to a system of three nonlinear ordinary differential equations. The equations are made dimensionless and a parametric study is performed where the effects of various dimensionless numbers representing the effects of heat conduction, viscous dissipation, radiation, and so forth are presented.

Massoudi, M.C.; Tran, P.X.

2006-01-01T23:59:59.000Z

203

Quantitative photoacoustic imaging in radiative transport regime  

E-Print Network [OSTI]

, radiative transport equation, inverse transport problem, interior data, Born approximation, iterative is accurately modeled by the radiative transport equation which describes the distribution of photons . The radiative transport equation for photon density u(x, v) can then be written as [9, 11, 77]: v · u(x, v) + a

Ren, Kui

204

Radiation transport modeling using extended quadrature method of moments  

SciTech Connect (OSTI)

The radiative transfer equation describes the propagation of radiation through a material medium. While it provides a highly accurate description of the radiation field, the large phase space on which the equation is defined makes it numerically challenging. As a consequence, significant effort has gone into the development of accurate approximation methods. Recently, an extended quadrature method of moments (EQMOM) has been developed to solve univariate population balance equations, which also have a large phase space and thus face similar computational challenges. The distinct advantage of the EQMOM approach over other moment methods is that it generates moment equations that are consistent with a positive phase space density and has a moment inversion algorithm that is fast and efficient. The goal of the current paper is to present the EQMOM method in the context of radiation transport, to discuss advantages and disadvantages, and to demonstrate its performance on a set of standard one-dimensional benchmark problems that encompass optically thin, thick, and transition regimes. Special attention is given in the implementation to the issue of realizabilitythat is, consistency with a positive phase space density. Numerical results in one dimension are promising and lay the foundation for extending the same framework to multiple dimensions.

Vikas, V., E-mail: vvikas@iastate.edu [Department of Aerospace Engineering, 2271 Howe Hall, Iowa State University, Ames, IA 50011 (United States); Hauck, C.D., E-mail: hauckc@ornl.gov [Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wang, Z.J., E-mail: zjw@ku.edu [Department of Aerospace Engineering, 2120 Learned Hall, University of Kansas, Lawrence, KS 66045 (United States); Fox, R.O., E-mail: rofox@iastate.edu [Department of Chemical and Biological Engineering, 2114 Sweeney Hall, Iowa State University, Ames, IA 50011 (United States)

2013-08-01T23:59:59.000Z

205

Heat Transfer Derivation of differential equations for heat transfer conduction  

E-Print Network [OSTI]

) or kW *h or Btu. U is the change in stored energy, in units of kW *h (kWh) or Btu. qx is the heat conducted (heat flux) into the control volume at surface edge x, in units of kW/m2 or Btu/(h-ft2). qx volume is positive), in kW/m3 or Btu/(h-ft3) (a heat sink, heat drawn out of the volume, is negative

Veress, Alexander

206

Efficient natural defense mechanisms against Listeria monocytogenes in T and B cell-deficient allogeneic bone marrow radiation chimeras. Preactivated macrophages are the main effector cells in an early phase after bone marrow transfer  

SciTech Connect (OSTI)

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.

Roesler, J.; Groettrup, E.B.; Baccarini, M.; Lohmann-Mattes, M.L. (Fraunhofer-Institut ITA, Hannover (Germany, F.R.))

1989-09-01T23:59:59.000Z

207

E-Print Network 3.0 - abscopal radiation effects Sample Search...  

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

will introduce the theory of radiative transfer; the second part Summary: to greenhouse effect and solar radiation 6. Radiative heating and cooling a. The Chapman layer b....

208

AOI 1 COMPUTATIONAL ENERGY SCIENCES:MULTIPHASE FLOW RESEARCH High-fidelity multi-phase radiation module for modern coal combustion systems  

SciTech Connect (OSTI)

The effects of radiation in particle-laden flows were the object of the present research. The presence of particles increases optical thickness substantially, making the use of the optically thin approximation in most cases a very poor assumption. However, since radiation fluxes peak at intermediate optical thicknesses, overall radiative effects may not necessarily be stronger than in gas combustion. Also, the spectral behavior of particle radiation properties is much more benign, making spectral models simpler (and making the assumption of a gray radiator halfway acceptable, at least for fluidized beds when gas radiation is not large). On the other hand, particles scatter radiation, making the radiative transfer equation (RTE) much more di#14;fficult to solve. The research carried out in this project encompassed three general areas: (i) assessment of relevant radiation properties of particle clouds encountered in fluidized bed and pulverized coal combustors, (ii) development of proper spectral models for gasparticulate mixtures for various types of two-phase combustion flows, and (iii) development of a Radiative Transfer Equation (RTE) solution module for such applications. The resulting models were validated against artificial cases since open literature experimental data were not available. The final models are in modular form tailored toward maximum portability, and were incorporated into two research codes: (i) the open-source CFD code OpenFOAM, which we have extensively used in our previous work, and (ii) the open-source multi-phase flow code MFIX, which is maintained by NETL.

Modest, Michael

2013-11-15T23:59:59.000Z

209

E-Print Network 3.0 - atmospheric diffusion equation Sample Search...  

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

grey atmospheres Defining the radiation field (specific intensity, moments, fluxes) Equation... equation. Basic assumptions for a magnetized fluid Derivation of the ... Source:...

210

Measurements and modeling of soot formation and radiation in microgravity jet diffusion flames  

SciTech Connect (OSTI)

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.

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

211

Enhanced heat transfer for thermionic power modules  

SciTech Connect (OSTI)

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.

Johnson, D.C.

1981-07-01T23:59:59.000Z

212

ME 339 Heat Transfer ABET EC2000 syllabus  

E-Print Network [OSTI]

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

Ben-Yakar, Adela

213

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...

214

Efficient Phase-Change Materials: Development of a Low-Cost Thermal Energy Storage System Using Phase-Change Materials with Enhanced Radiation Heat Transfer  

SciTech Connect (OSTI)

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 nightwhen the sun is not outto 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. USFs PCMs remain stable at temperatures from 600 to 1,000C and can be used for solar thermal power storage, nuclear thermal power storage, and other applications.

None

2011-12-05T23:59:59.000Z

215

AndreiG.Fedorov Title: George W. Woodruff Professorship in Heat Transfer, Combustion and  

E-Print Network [OSTI]

AndreiG.Fedorov Title: George W. Woodruff Professorship in Heat Transfer, Combustion and Energy Research Areas of Interest Heat Transfer, combustion, and energy systems Bioengineering, lab ionization and imaging for bioanalytical mass spectrometry Thermal radiation heat transfer Thermal

Garmestani, Hamid

216

Development of a Heat Transfer Model for the Integrated Facade Heating  

E-Print Network [OSTI]

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...

Gong, X.; Archer, D. H.; Claridge, D. E.

2007-01-01T23:59:59.000Z

217

ME 544 Advanced Heat Transfer Spring 2013 Time: 2pm-3pm MWF  

E-Print Network [OSTI]

1 ME 544 Advanced Heat Transfer Spring 2013 Time: 2pm-3pm MWF Location: B4 Instructor: Dr. Allan and engineering applications of heat transfer including conduction, convection, and radiation. Course Learning, convection, and radiation heat transfer modes. 2. Determine the dominant modes of heat transfer, and apply

218

Rotating bubble membrane radiator  

DOE Patents [OSTI]

A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

1988-12-06T23:59:59.000Z

219

Dirac Equation in Standard Cosmological Models  

E-Print Network [OSTI]

The time equation associated to the Dirac Equation (DE) is studied for the radiation-dominated Friedmann-Robertson-Walker (FRW) universe. The results are analysed for small and large values of time. We also incorporate the corrections of the paper studied by Zecca [1] for the matter-dominated FRW universe.

M. Sharif

2004-01-15T23:59:59.000Z

220

Curcumin Regulates Low-Linear Energy Transfer {gamma}-Radiation-Induced NF{kappa}B-Dependent Telomerase Activity in Human Neuroblastoma Cells  

SciTech Connect (OSTI)

Purpose: We recently reported that curcumin attenuates ionizing radiation (IR)-induced survival signaling and proliferation in human neuroblastoma cells. Also, in the endothelial system, we have demonstrated that NF{kappa}B regulates IR-induced telomerase activity (TA). Accordingly, we investigated the effect of curcumin in inhibiting IR-induced NF{kappa}B-dependent hTERT transcription, TA, and cell survival in neuroblastoma cells. Methods and Materials: SK-N-MC or SH-SY5Y cells exposed to IR and treated with curcumin (10-100 nM) with or without IR were harvested after 1 h through 24 h. NF{kappa}B-dependent regulation was investigated either by luciferase reporter assays using pNF{kappa}B-, pGL3-354-, pGL3-347-, or pUSE-I{kappa}B{alpha}-Luc, p50/p65, or RelA siRNA-transfected cells. NF{kappa}B activity was analyzed using an electrophoretic mobility shift assay and hTERT expression using the quantitative polymerase chain reaction. TA was determined using the telomerase repeat amplification protocol assay and cell survival using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltertrazolium bromide and clonogenic assay. Results: Curcumin profoundly inhibited IR-induced NF{kappa}B. Consequently, curcumin significantly inhibited IR-induced TA and hTERT mRNA at all points investigated. Furthermore, IR-induced TA is regulated at the transcriptional level by triggering telomerase reverse transcriptase (TERT) promoter activation. Moreover, NF{kappa}B becomes functionally activated after IR and mediates TA upregulation by binding to the {kappa}B-binding region in the promoter region of the TERT gene. Consistently, elimination of the NF{kappa}B-recognition site on the telomerase promoter or inhibition of NF{kappa}B by the I{kappa}B{alpha} mutant compromises IR-induced telomerase promoter activation. Significantly, curcumin inhibited IR-induced TERT transcription. Consequently, curcumin inhibited hTERT mRNA and TA in NF{kappa}B overexpressed cells. Furthermore, curcumin enhanced the IR-induced inhibition of cell survival. Conclusions: These results strongly suggest that curcumin inhibits IR-induced TA in an NF{kappa}B dependent manner in human neuroblastoma cells.

Aravindan, Natarajan, E-mail: naravind@ouhsc.ed [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Veeraraghavan, Jamunarani; Madhusoodhanan, Rakhesh; Herman, Terence S. [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Natarajan, Mohan [Department of Otolaryngology, Head and Neck Surgery, University of Texas Health Sciences Center at San Antonio, San Antonio, TX (United States)

2011-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

EXISTENCE AND UNIQUENESS OF SOLUTIONS OF NONLINEAR SYSTEMS OF CONDUCTIVERADIATIVE HEAT TRANSFER  

E-Print Network [OSTI]

of the equations as described in [5], [9], and [8]. The radiative transport equation is ¯ @/ @x (x; ¯) + /(x of nonlinear integro­ differential equations that model steady­state combined radiative­conductive heat for coupled radiative­conductive heat transport are discussed. These models can be expressed as nonlinear

222

Unruh radiation and Interference effect  

E-Print Network [OSTI]

A uniformly accelerated charged particle feels the vacuum as thermally excited and fluctuates around the classical trajectory. Then we may expect additional radiation besides the Larmor radiation. It is called Unruh radiation. In this report, we review the calculation of the Unruh radiation with an emphasis on the interference effect between the vacuum fluctuation and the radiation from the fluctuating motion. Our calculation is based on a stochastic treatment of the particle under a uniform acceleration. The basics of the stochastic equation are reviewed in another report in the same proceeding. In this report, we mainly discuss the radiation and the interference effect.

Satoshi Iso; Yasuhiro Yamamoto; Sen Zhang

2011-02-23T23:59:59.000Z

223

Journal of Statistical Physics, Vol. 95, Nos. 12, 1999 Radiative Transport in a Periodic Structure  

E-Print Network [OSTI]

; final December 1, 1998 We derive radiative transport equations for solutions of a Schrodinger equation and the Bloch wave expansion. The streaming part of the radiative transport equations is determined entirely Radiative transport equations describe propagation of the phase space energy density of high frequency waves

Fannjiang, Albert

224

PARALLELIZATION OF THE P-1 RADIATION MODEL Gautham Krishnamoorthy, Rajesh Rawat, and Philip J. Smith  

E-Print Network [OSTI]

radiation model is spatially decomposed to solve the radiative transport equation on parallel computers describes the paralle- lization of the P-1 approximation to the radiative transport equation (RTE to the discretized transport equations consumes the maximum time in most radiation algorithms. Therefore, the speed

Utah, University of

225

Heat Transfer in Complex Fluids  

SciTech Connect (OSTI)

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

Mehrdad Massoudi

2012-01-01T23:59:59.000Z

226

The Intense Radiation Gas  

E-Print Network [OSTI]

We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon-photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for interacting photons is formulated. The interaction between an electromagnetic pulse and the radiation gas is shown to produce pulse self-compression and nonlinear saturation. Implications of our new results are discussed.

M. Marklund; P. K. Shukla; B. Eliasson

2005-03-08T23:59:59.000Z

227

A unified radiative magnetohydrodynamics code for lightning-like discharge simulations  

SciTech Connect (OSTI)

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.

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

228

Radiative Transfer in Reflection Edvald Ingi Gislason  

E-Print Network [OSTI]

unique skills and deep understanding of the theory involved proved vital to the success of this project coming from stars within them. With development of new algorithms and hardware, improvements can be made

229

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia51 Posters A594173619

230

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia51 Posters7551773313

231

Sandia National Laboratories: understanding radiative energy 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmitted for USMaterialstheterahertz sources and detectorsunderstanding

232

Transport Equations for Elastic and Other Waves in Random Leonid Ryzhik, George Papanicolaou and Joseph B. Keller  

E-Print Network [OSTI]

. Contents 1 Introduction and Summary 2 1.1 Radiative Transport Equations : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 10 2 Radiative Transport Theory for the Schr¨odinger Equation 11 2.1 High Frequency Asymptotics expansion for the Transport Approximation 55 1 Introduction and Summary 1.1 Radiative Transport Equations

Ryzhik, Lenya

233

Transport Equations for Elastic and Other Waves in Random Leonid Ryzhik, George Papanicolaou and Joseph B. Keller  

E-Print Network [OSTI]

. Contents 1 Introduction and Summary 2 1.1 Radiative Transport Equations : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 10 2 Radiative Transport Theory for the Schrodinger Equation 11 2.1 High Frequency Asymptotics expansion for the Transport Approximation 55 1 Introduction and Summary 1.1 Radiative Transport Equations

Papanicolaou, George C.

234

A GEOMETRIC DERIVATION OF THE LINEAR BOLTZMANN EQUATION FOR A PARTICLE INTERACTING WITH A  

E-Print Network [OSTI]

] the radiative transport equation in the spatially homogenous case. Later Ho, Landau and Wilkins studied in [29 Boltzmann equation was derived in the radiative transport limit by Bal, Papanicolaou and Ryzhik [5A GEOMETRIC DERIVATION OF THE LINEAR BOLTZMANN EQUATION FOR A PARTICLE INTERACTING WITH A GAUSSIAN

Paris-Sud XI, Université de

235

Radiative transport limit for the random Schrodinger Guillaume Bal  

E-Print Network [OSTI]

Radiative transport limit for the random Schr¨odinger equation Guillaume Bal George Papanicolaou converges to the solution of a radiative transport equation. The propagation of wave energy in a scattering Leonid Ryzhik May 8, 2002 Abstract We give a detailed mathematical analysis of the radiative transport

Papanicolaou, George C.

236

Data 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINL is aID Service First DOIData Transfer

237

Transferring Data  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2Topo II: AnTraining andfor a CleanTransfer Service,

238

Transferring Data  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2Topo II: AnTraining andfor a CleanTransfer

239

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,...

240

A GPU Parallelized Spectral Method For Elliptic Equations.  

E-Print Network [OSTI]

ence methods [6], finite element methods [24, 14, 13], Fourier spectral methods .... stored on the GPU once and for all, in order to minimize data transfer between the ..... The spectrum of the Chebyshev collocation operator for the heat equation.

2013-04-29T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Dynamics of heat transfer between nano systems  

E-Print Network [OSTI]

We develop a dynamical theory of heat transfer between two nano systems. In particular, we consider the resonant heat transfer between two nanoparticles due to the coupling of localized surface modes having a finite spectral width. We model the coupled nanosystem by two coupled quantum mechanical oscillators, each interacting with its own heat bath, and obtain a master equation for the dynamics of heat transfer. The damping rates in the master equation are related to the lifetimes of localized plasmons in the nanoparticles. We study the dynamics towards the steady state and establish connection with the standard theory of heat transfer in steady state. For strongly coupled nano particles we predict Rabi oscillations in the mean occupation number of surface plasmons in each nano particle.

Svend-Age Biehs; Girish S. Agarwal

2012-10-18T23:59:59.000Z

242

Heat Transfer between Graphene and Amorphous SiO2  

E-Print Network [OSTI]

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.

B. N. J. Persson; H. Ueba

2010-07-22T23:59:59.000Z

243

The Cosmic Equation of State  

E-Print Network [OSTI]

The cosmic spacetime is often described in terms of the FRW metric, though the adoption of this elegant and convenient solution to Einstein's equations does not tell us much about the equation of state, p=w rho, in terms of the total energy density rho and pressure p of the cosmic fluid. LCDM and the R_h=ct Universe are both FRW cosmologies that partition rho into (at least) three components, matter rho_m, radiation rho_r, and a poorly understood dark energy rho_de, though the latter goes one step further by also invoking the constraint w=-1/3. This condition is required by the simultaneous application of the Cosmological principle and Weyl's postulate. Model selection tools in one-on-one comparisons favor R_h=ct with a likelihood of ~90% versus only ~10% for LCDM. Nonetheless, the predictions of LCDM often come quite close to those of R_h=ct, suggesting that its parameters are optimized to mimic the w=-1/3 equation of state. In this paper, we demonstrate that the equation of state in R_h=ct helps us to understand why the optimized fraction Omega_m=rho_m/rho in LCDM must be ~0.27, an otherwise seemingly random variable. We show that when one forces LCDM to satisfy the equation of state w=(rho_r/3-rho_de)/rho, the value of the Hubble radius today, c/H_0, can equal its measured value ct_0 only with Omega_m~0.27 when the equation of state for dark energy is w_de=-1. This peculiar value of Omega_m therefore appears to be a direct consequence of trying to fit the data with the equation of state w=(rho_r/3-rho_de)/rho in a Universe whose principal constraint is instead R_h=ct or, equivalently, w=-1/3.

Fulvio Melia

2014-11-21T23:59:59.000Z

244

FACET: a radiation view factor computer code for axisymmetric, 2D planar, and 3D geometries with shadowing  

SciTech Connect (OSTI)

The computer code FACET calculates the radiation geometric view factor (alternatively called shape factor, angle factor, or configuration factor) between surfaces for axisymmetric, two-dimensional planar and three-dimensional geometries with interposed third surface obstructions. FACET was developed to calculate view factors for input to finite-element heat-transfer analysis codes. The first section of this report is a brief review of previous radiation-view-factor computer codes. The second section presents the defining integral equation for the geometric view factor between two surfaces and the assumptions made in its derivation. Also in this section are the numerical algorithms used to integrate this equation for the various geometries. The third section presents the algorithms used to detect self-shadowing and third-surface shadowing between the two surfaces for which a view factor is being calculated. The fourth section provides a user's input guide followed by several example problems.

Shapiro, A.B.

1983-08-01T23:59:59.000Z

245

Radiative transport limit for the random Schrodinger Guillaume Bal George Papanicolaou y Leonid Ryzhik z  

E-Print Network [OSTI]

Radiative transport limit for the random Schrodinger equation Guillaume Bal #3; George of the radiative transport limit for the average phase space density of solutions of the Schrodinger equation to the solution of a radiative transport equation. The propagation of wave energy in a scattering medium

Ryzhik, Lenya

246

RADIATION MONITORING  

E-Print Network [OSTI]

of Monitoring for Radiation Protection of Workers" in ICRPNo. 9, in "Advances in Radiation Protection and Dosimetry inDosimetry f o r Stray Radiation Monitoring on the CERN S i t

Thomas, R.H.

2010-01-01T23:59:59.000Z

247

FALL 2011 EMEC 326 DR. RUHUL AMIN HEAT TRANSFER 201 C Roberts Hall  

E-Print Network [OSTI]

FALL 2011 EMEC 326 DR. RUHUL AMIN HEAT TRANSFER 201 C Roberts Hall Phone: 994-6295 POLICY STATEMENT, convection, and radiation formulations. Introduction to heat transfer equipment. Course credit: 4

Dyer, Bill

248

The Cosmic Equation of State  

E-Print Network [OSTI]

The cosmic spacetime is often described in terms of the FRW metric, though the adoption of this elegant and convenient solution to Einstein's equations does not tell us much about the equation of state, p=w rho, in terms of the total energy density rho and pressure p of the cosmic fluid. LCDM and the R_h=ct Universe are both FRW cosmologies that partition rho into (at least) three components, matter rho_m, radiation rho_r, and a poorly understood dark energy rho_de, though the latter goes one step further by also invoking the constraint w=-1/3. This condition is required by the simultaneous application of the Cosmological principle and Weyl's postulate. Model selection tools in one-on-one comparisons favor R_h=ct with a likelihood of ~90% versus only ~10% for LCDM. Nonetheless, the predictions of LCDM often come quite close to those of R_h=ct, suggesting that its parameters are optimized to mimic the w=-1/3 equation of state. In this paper, we demonstrate that the equation of state in R_h=ct helps us to under...

Melia, Fulvio

2014-01-01T23:59:59.000Z

249

Radiation in (2+1)-dimensions  

E-Print Network [OSTI]

In this paper we discuss the radiation equation of state $p=\\rho/2$ in (2+1)-dimensions. In (3+1)-dimensions the equation of state $p=\\rho/3$ may be used to describe either actual electromagnetic radiation (photons) as well as a gas of massless particles in a thermodynamic equilibrium (for example neutrinos). In this work it is shown that in the framework of (2+1)-dimensional Maxwell electrodynamics the radiation law $p=\\rho/2$ takes place only for plane waves, i.e. for $E = B$. Instead of the linear Maxwell electrodynamics, to derive the (2+1)-radiation law for more general cases with $E \

Mauricio Cataldo; Alberto A. Garca

2014-05-15T23:59:59.000Z

250

A Gentle Introduction to Precomputed Radiance Transfer  

E-Print Network [OSTI]

in computer graphics, and many algorithms have been developed to try to reproduce the visual complexity with the support of modern graphics hardware. Precomputed Radiance Transfer (PRT) is a new graphics technique of the rendering equation to a subset of the light transport paths that handle only energy exchange among diffuse

Oliveira, Manuel M.

251

RADIATIVE RAYLEIGH-TAYLOR INSTABILITIES  

SciTech Connect (OSTI)

We perform analytic linear stability analyses of an interface separating two stratified media threaded by a radiation flux, a configuration relevant in several astrophysical contexts. We develop a general framework for analyzing such systems and obtain exact stability conditions in several limiting cases. In the optically thin, isothermal regime, where the discontinuity is chemical in nature (e.g., at the boundary of a radiation pressure-driven H II region), radiation acts as part of an effective gravitational field, and instability arises if the effective gravity per unit volume toward the interface overcomes that away from it. In the optically thick 'adiabatic' regime where the total (gas plus radiation) specific entropy of a Lagrangian fluid element is conserved, for example at the edge of radiation pressure-driven bubble around a young massive star, we show that radiation acts like a modified equation of state and derive a generalized version of the classical Rayleigh-Taylor stability condition.

Jacquet, Emmanuel [Laboratoire de Mineralogie et Cosmochimie de Museum (LMCM), CNRS and Museum National d'Histoire Naturelle, UMR 7202, 57 rue Cuvier, 75005 Paris (France); Krumholz, Mark R., E-mail: ejacquet@mnhn.fr, E-mail: krumholz@ucolick.org [Department of Astronomy, University of California, Santa Cruz, CA 95064 (United States)

2011-04-01T23:59:59.000Z

252

Heat transfer in proteinwater interfaces Anders Lervik,ab  

E-Print Network [OSTI]

Heat transfer in protein­water interfaces Anders Lervik,ab Fernando Bresme,*ac Signe Kjelstrup of the heat diffusion equation we compute the thermal conductivity and thermal diffusivity of the proteins by about 4 nm.4 It is expected that the energy transfer between these sites may involve the concerted

Kjelstrup, Signe

253

Solar Radiation and Asteroidal Motion  

E-Print Network [OSTI]

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.

Jozef Klacka

2000-09-07T23:59:59.000Z

254

Passive-solar directional-radiating cooling system  

DOE Patents [OSTI]

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.

Hull, J.R.; Schertz, W.W.

1985-06-27T23:59:59.000Z

255

Passive-solar directional-radiating cooling system  

DOE Patents [OSTI]

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.

Hull, John R. (Hinsdale, IL); Schertz, William W. (Batavia, IL)

1986-01-01T23:59:59.000Z

256

IntroductiontoProcessEngineering(PTG) 5. Heat transfer  

E-Print Network [OSTI]

#5/6 IntroductiontoProcessEngineering(PTG) VST rz13 1/114 5. Heat transfer Ron Zevenhoven ?boProcessEngineering(PTG) VST rz13 Three heat transfer mechanisms Conduction Convection Radiation 2/114 Pic: B?88 #12;#5/6 IntroductiontoProcessEngineering(PTG) VST rz13 3/114 5.1 Conductive heat transfer #5/6 Introductionto

Zevenhoven, Ron

257

Cooperative heat transfer and ground coupled storage system  

DOE Patents [OSTI]

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.

Metz, Philip D. (Rocky Point, NY)

1982-01-01T23:59:59.000Z

258

Federal Laboratory Technology Transfer  

E-Print Network [OSTI]

Federal Laboratory Technology Transfer Fiscal Year 2008 Prepared by: National Institute to submit this fiscal year 2008 Technology Transfer Summary Report to the President and the Congress transfer authorities established by the Technology Transfer Commercialization Act of 2000 (P.L. 106

Perkins, Richard A.

259

7, 72357275, 2007 Adaptive radiative  

E-Print Network [OSTI]

Discussions Two adaptive radiative transfer schemes for numerical weather prediction models V. Venema 1 , A numerical weather prediction (NWP) and climate models. The atmosphere and the land surface are complex-stream approximation. In most weather prediction models these parameterisation schemes are therefore called infre

Boyer, Edmond

260

Equation for liquid density  

SciTech Connect (OSTI)

Saturated liquid densities for organic chemicals are given as functions of temperature using a modified Rackett equation.

Yaws, C.L.; Yang, H.C.; Hopper, J.R.; Cawley, W.A. (Lamar Univ., Beaumont, TX (US))

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Danger radiations  

ScienceCinema (OSTI)

Le confrencier Mons.Hofert parle des dangers et risques des radiations, le contrle des zones et les prcautions prendre ( p.ex. film badge), comment mesurer les radiations etc.

None

2011-04-25T23:59:59.000Z

262

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, OctoberDecember 2000  

E-Print Network [OSTI]

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 14, No. 4, October­December 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

Guo, Zhixiong "James"

263

Matter Wave Radiation Leading to Matter Teleportation  

E-Print Network [OSTI]

The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.

Yong-Yi Huang

2015-02-12T23:59:59.000Z

264

Anisotropic radiation from accretion disc-coronae in active galactic nuclei  

E-Print Network [OSTI]

In the unification scheme of active galactic nuclei (AGN), Seyfert 1s and Seyfert 2s are intrinsically same, but they are viewed at different angles. However, the Fe K\\alpha emission line luminosity of Seyfert 1s was found in average to be about twice of that of Seyfert 2s at given X-ray continuum luminosity in the previous work (Ricci et al. 2014). We construct an accretion disc-corona model, in which a fraction of energy dissipated in the disc is extracted to heat the corona above the disc. The radiation transfer equation containing Compton scattering processes is an integro-differential equation, which is solved numerically for the corona with a parallel plane geometry. We find that the specific intensity of X-ray radiation from the corona changes little with the viewing angle \\theta when \\theta is small (nearly face-on), and it is sensitive to \\theta if the viewing angle is large (\\theta> 40 degrees). The radiation from the cold disc, mostly in infrared/optical/UV bands, is almost proportional to cos\\thet...

Xu, Ya-Di

2015-01-01T23:59:59.000Z

265

Estimating optical properties in layered tissues by use of the Born approximation of the radiative  

E-Print Network [OSTI]

of the radiative transport equation to recover simultaneously the absorption and scattering coefficients approximation of the radiative transport equation (RTE).1­3 These methods are lim- ited to systems whose reduced transport equation Arnold D. Kim School of Natural Science, University of California, Merced, P. O. Box 2039

Kim, Arnold D.

266

HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME  

E-Print Network [OSTI]

1 HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME P. H or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers-dimensional numerical simulation of the heat transfers through the double skin reveals the most important parameters

Boyer, Edmond

267

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Window Frames  

E-Print Network [OSTI]

1 Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer Arasteh and Dragan Curcija ABSTRACT Accurately analyzing heat transfer in window frame cavities radiation heat-transfer effects.) We examine three representative complex cavity cross-section profiles

268

A unifying mechanical equation with applications to non-holonomic constraints and dissipative phenomena  

E-Print Network [OSTI]

A mechanical covariant equation is introduced which retains all the effectingness of the Lagrange equation while being able to describe in a unified way other phenomena including friction, non-holonomic constraints and energy radiation (Lorentz-Abraham-Dirac force equation). A quantization rule adapted to the dissipative degrees of freedom is proposed which does not pass through the variational formulation.

E. Minguzzi

2014-10-01T23:59:59.000Z

269

Constructing a Model Transport Equation for a Massless Bose Gas and its Analytic Solution  

E-Print Network [OSTI]

A model kinetic equation is constructed for the transport of a massless Bose gas. This equation is applied to solution of the boundary value problem for the transport of radiation in the half-space occupied by a dispersive medium that is in local thermal equilibrium with the radiation. It is shown that the difference in temperature between the dispersive medium and the incident radiation depends substantially on the character of the scattering properties of the particles of the medium.

A. V. Latyshev; A. A. Yushkanov

2010-12-14T23:59:59.000Z

270

HEAT TRANSFER FLUIDS  

E-Print Network [OSTI]

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 ...

Lenert, Andrej

2012-01-01T23:59:59.000Z

271

Solutions of Penrose's Equation  

E-Print Network [OSTI]

The computational use of Killing potentials which satisfy Penrose's equation is discussed. Penrose's equation is presented as a conformal Killing-Yano equation and the class of possible solutions is analyzed. It is shown that solutions exist in spacetimes of Petrov type O, D or N. In the particular case of the Kerr background, it is shown that there can be no Killing potential for the axial Killing vector.

E. N. Glass; Jonathan Kress

1998-09-27T23:59:59.000Z

272

INL Technology Transfer  

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

Technology Transfer Through collaboration with industry partners, INL's Technology Deployment office makes available to American agencies and international organizations unique...

273

Radiative transport theory for light propagation in luminescent media  

E-Print Network [OSTI]

the radiative transport equation (RTE) [1,2]. It has been applied successfully to many prob- lemsRadiative transport theory for light propagation in luminescent media Derya ahin* and Boaz Ilan of radiative transport theory to account for light propagation in luminescent random media. This theory

Ilan, Boaz

274

Heat Transfer Guest Editorial  

E-Print Network [OSTI]

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

Kandlikar, Satish

275

Federal Laboratory Technology Transfer  

E-Print Network [OSTI]

Federal Laboratory Technology Transfer Fiscal Year 2007 Prepared by: National Institute to present to the President and the Congress this Federal Laboratory Technology Transfer Report summarizing the achievements of Federal technology transfer and partnering programs of the Federal research and development

Perkins, Richard A.

276

Federal Laboratory Technology Transfer  

E-Print Network [OSTI]

Federal Laboratory Technology Transfer Fiscal Year 2009 Prepared by: National Institute to submit this fiscal year 2009 Technology Transfer Summary Report to the President and the Congress in accordance with 15 USC Sec 3710(g)(2) for an annual summary on the implementation of technology transfer

Perkins, Richard A.

277

ENHANCING THE TRANSFER STUDENT  

E-Print Network [OSTI]

Efforts #12;Who Are Ohio State Transfer Students? #12;TRANSFER PROFILE DatafromSU12,AU12,SP13 3 as NFYS: 576 Average Transfer Hours of Enrolled Student: 52.2 Living on Campus: 470 Total # Sending Expectations (time management skills, balancing a more rigorous course load, study skills) 13.24% Majors (how

278

Comments on initial conditions for the Abraham-Lorentz(-Dirac) equation  

E-Print Network [OSTI]

An accelerating electric charge coupled to its own electromagnetic (EM) field both emits radiation and experiences the radiation's reaction as a (self-)force. Considering the system from an Effective Field Theory perspective, and using the physical initial conditions of no incoming radiation can help resolve many of the problems associated with the often considered "notorious" Abraham-Lorentz / Abraham-Lorentz-Dirac equations.

Ofek Birnholtz

2014-10-21T23:59:59.000Z

279

E-Print Network 3.0 - aerosol direct radiative Sample Search...  

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

Transfer Encyclopedia of Atmospheric Science William D. Collins... system. Naturally occurring aerosols reflect some of the incident solar radiation back to space before... the...

280

Heat transfer system  

DOE Patents [OSTI]

A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

McGuire, Joseph C. (Richland, WA)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Heat transfer system  

DOE Patents [OSTI]

A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

Not Available

1980-03-07T23:59:59.000Z

282

Radiation detector  

DOE Patents [OSTI]

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, Brent T. (Berkeley, CA)

1983-01-01T23:59:59.000Z

283

Radiation detector  

DOE Patents [OSTI]

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.

Fultz, B.T.

1980-12-05T23:59:59.000Z

284

Surface Power Radiative Cooling Tests  

SciTech Connect (OSTI)

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.

Vaughn, Jason; Schneider, Todd [Environmental Effects Branch, EM50, NASA Marshall Space Flight Center, AL 35812 (United States)

2006-01-20T23:59:59.000Z

285

ON THE SOLAR RADIATION BUDGET AND THE CLOUD ABSORPTION ANOMALY DEBATE  

E-Print Network [OSTI]

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

Li, Zhanqing

286

Nonlinear gyrokinetic equations  

SciTech Connect (OSTI)

Nonlinear gyrokinetic equations are derived from a systematic Hamiltonian theory. The derivation employs Lie transforms and a noncanonical perturbation theory first used by Littlejohn for the simpler problem of asymptotically small gyroradius. For definiteness, we emphasize the limit of electrostatic fluctuations in slab geometry; however, there is a straight-forward generalization to arbitrary field geometry and electromagnetic perturbations. An energy invariant for the nonlinear system is derived, and various of its limits are considered. The weak turbulence theory of the equations is examined. In particular, the wave kinetic equation of Galeev and Sagdeev is derived from an asystematic truncation of the equations, implying that this equation fails to consider all gyrokinetic effects. The equations are simplified for the case of small but finite gyroradius and put in a form suitable for efficient computer simulation. Although it is possible to derive the Terry-Horton and Hasegawa-Mima equations as limiting cases of our theory, several new nonlinear terms absent from conventional theories appear and are discussed.

Dubin, D.H.E.; Krommes, J.A.; Oberman, C.; Lee, W.W.

1983-03-01T23:59:59.000Z

287

Efficient Conservative Numerical Schemes for 1D Nonlinear Spherical Diffusion Equations with Applications in Battery Modeling  

E-Print Network [OSTI]

Mathematical models of batteries which make use of the intercalation of a species into a solid phase need to solve the corresponding mass transfer problem. Because solving this equation can significantly add to the ...

Zeng, Yi

288

E-Print Network 3.0 - agents uv radiation Sample Search Results  

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

has been... is needed. Equation 1 was initially developed for organisms exposed to a dose Eeff of UV radiation... in which there will be UV radiation present. In the ......

289

Radiation dosimeter  

DOE Patents [OSTI]

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even though the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, Richard J. (Oak Ridge, TN)

1983-01-01T23:59:59.000Z

290

Radiation dosimeter  

DOE Patents [OSTI]

A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even through the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display.

Fox, R.J.

1981-09-01T23:59:59.000Z

291

E-Print Network 3.0 - astrophysical radiation hydrodynamics Sample...  

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

Hydrodynamics of HED... and materials at high pressure Radiation hydrodynamics Equation of state of HED plasma and materials at high... transport of energy Laserparticle...

292

Expanding, axisymmetric pure-radiation gravitational fields with a simple twist  

E-Print Network [OSTI]

New expanding, axisymmetric pure-radiation solutions are found, exploiting the analogy with the Euler-Darboux equation for aligned colliding plane waves.

B. V. Ivanov

2001-03-27T23:59:59.000Z

293

E-Print Network 3.0 - anthropogenic radiation sources Sample...  

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

: Ts F Equation 1 The largest radiative forcing is due to the anthropogenic greenhouse effect... impact" of an anthropogenic perturbation. This is defined as the difference...

294

Fuel transfer system  

DOE Patents [OSTI]

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.

Townsend, H.E.; Barbanti, G.

1994-03-01T23:59:59.000Z

295

MODELING HEAT TRANSFER IN SPENT FUEL TRANSFER CASK NEUTRON SHIELDS A CHALLENGING PROBLEM IN NATURAL CONVECTION  

SciTech Connect (OSTI)

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.

Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.

2010-07-18T23:59:59.000Z

296

HIGEE Mass Transfer  

E-Print Network [OSTI]

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...

Mohr, R. J.; Fowler, R.

297

The Modified Dirac Equation  

E-Print Network [OSTI]

We consider the behavior of the particles at ultra relativistic energies, for both the Klein-Gordon and Dirac equations. We observe that the usual description is valid for energies such that we are outside the particle's Compton wavelength. For higher energies however, both the Klein-Gordon and Dirac equations get modified and this leads to some new effects for the particles, including the appearance of anti particles with a slightly different energy.

Burra G. Sidharth

2009-11-10T23:59:59.000Z

298

MATERIALS TRANSFER AGREEMENT  

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...

299

Bus transfer analysis  

SciTech Connect (OSTI)

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.

Weronick, R.; Hassan, I.D. [Raytheon Engineers and Constructors, Lyndhurst, NJ (United States)

1996-11-01T23:59:59.000Z

300

Technology Transfer Reports  

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...

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Facility Survey & Transfer  

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.

302

Accurate solution and approximations of the linearized bgk equation ...  

E-Print Network [OSTI]

Jan 7, 2015 ... We present an accurate and efficient high-order collocation method to solve the integral equation with a singular kernel ..... where A is an N ? N matrix whose element is amn ? An?ym?, and b and c are ...... some classical problems in flow and heat transfer. .... Algorithms for the numerical solution of a finite-.

Wei Li

2015-01-30T23:59:59.000Z

303

Heat transfer enhancement in a channel with porous baffles  

E-Print Network [OSTI]

with staggered positioned porous baffles. A numerical procedure was implemented, in conjunction with a commercially available Navier-Stokes solver, to model the turbulent flow in porous media. The Brinkman-Forchheimer-Extended Darcy model was used for modeling... fluid flow through the porous baffles. Conventional, one- equation, and two-equation models were used for heat transfer modeling. The accuracy and characteristics of each model were investigated and discussed. The results were compared...

Ko, Kang-Hoon

2005-02-17T23:59:59.000Z

304

REMOTE AREA RADIATION MONITORING (RARM) ALTERNATIVES ANALYSIS  

SciTech Connect (OSTI)

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.

NELSON RL

2008-07-18T23:59:59.000Z

305

RADIATION SAFETY TRAINING MANUAL Radiation Safety Office  

E-Print Network [OSTI]

RADIATION SAFETY TRAINING MANUAL Radiation Safety Office 130 DeSoto Street G-7 Parran with sources of ionizing radiation are required to be instructed in the basic principles of radiation protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide

Sibille, Etienne

306

Appendix G. Radiation Appendix G. Radiation  

E-Print Network [OSTI]

-made sources. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation of radiation and its effects on the environment and biological systems. Radiation comes from natural and humanAppendix G. Radiation #12;#12;Appendix G. Radiation This appendix presents basic facts about

Pennycook, Steve

307

11th International Conference of Radiation Research  

SciTech Connect (OSTI)

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.

NONE

1999-07-18T23:59:59.000Z

308

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

E-Print Network [OSTI]

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

De Castro, Carlos Armando

2011-01-01T23:59:59.000Z

309

SWAMI II technology transfer plan  

SciTech Connect (OSTI)

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.

Ward, C.R.; Peterson, K.D.; Harpring, L.J.; Immel, D.M.; Jones, J.D.; Mallet, W.R.

1995-12-31T23:59:59.000Z

310

Numerical treatment of the hyperboloidal initial value problem for the vacuum Einstein equations. II. The evolution equations  

E-Print Network [OSTI]

This is the second in a series of articles on the numerical solution of Friedrich's conformal field equations for Einstein's theory of gravity. We will discuss in this paper the numerical methods used to solve the system of evolution equations obtained from the conformal field equations. In particular we discuss in detail the choice of gauge source functions and the treatment of the boundaries. Of particular importance is the process of ``radiation extraction'' which can be performed in a straightforward way in the present formalism.

J. Frauendiener

1997-12-11T23:59:59.000Z

311

Design/installation and structural integrity assessment under the Federal Facility Agreement for Bethel Valley Low-Level Waste Collection and Transfer System upgrade for Building 2026 (High Radiation Level Analytical Laboratory) and Building 2099 (Monitoring and Control Station) at Oak Ridge National Laboratory  

SciTech Connect (OSTI)

This document presents a Design/Installation and Structural Integrity Assessment for a replacement tank system for portions of the Bethel Valley Low Level Waste (LLW) System, located at the Oak Ridge Reservation, Oak Ridge, Tennessee. This issue of the assessment covers the design aspects of the replacement tank system, and certifies that the design has sufficient structural integrity and is acceptable for the storing or treating of hazardous and/or radioactive substances. The present issue identifies specific activities that must be completed during the fabrication, installation, and testing of the replacement tank system in order to provide assurance that the final installation complies with governing requirements. Portions of the LLW system are several decades old, or older, and do not comply with current environmental protection regulations. Several subsystems of the LLW system have been designated to receive a state-of-the-art replacement and refurbishment. One such subsystem serves Building 2026, the High Radiation Level Analytical Laboratory. This assessment focuses on the scope of work for the Building 2026 replacement LLW Collection and Transfer System, including the provision of a new Monitoring and Control Station (Building 2099) to receive, store, and treat (adjust pH) low level radioactive waste.

Not Available

1994-10-01T23:59:59.000Z

312

Energetics and Dynamics of Electron Transfer and Proton Transfer...  

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

Transfer in Dissociation of Metal III (salen)-Peptide Complexes in the Energetics and Dynamics of Electron Transfer and Proton Transfer in Dissociation of Metal III (salen)-Peptide...

313

Heat Transfer and Cooling Techniques at Low Temperature  

E-Print Network [OSTI]

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.

Baudouy, B

2014-01-01T23:59:59.000Z

314

Radiation receiver  

DOE Patents [OSTI]

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, A.J.

1983-09-13T23:59:59.000Z

315

Radiation receiver  

DOE Patents [OSTI]

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.

Hunt, Arlon J. (Oakland, CA)

1983-01-01T23:59:59.000Z

316

A new asymptotic preserving scheme based on micro-macro formulation for linear kinetic equations in the diffusion limit  

E-Print Network [OSTI]

of the particles is small, a macroscopic description--such as diffusion equation in neutron transport and radiative transport equations. It is based on a decomposition of the distribution function into equilibrium and non. transport equations, diffusion limit, asymptotic preserving schemes, stiff terms AMS subject classifications

Mieussens, Luc

317

Motion-induced radiation from electrons moving in Maxwell's fish-eye  

E-Print Network [OSTI]

In \\u{C}erenkov radiation and transition radiation, evanescent wave from motion of charged particles transfers into radiation coherently. However, such dissipative motion-induced radiations require particles to move faster than light in medium or to encounter velocity transition to pump energy. Inspired by a method to detect cloak by observing radiation of a fast-moving electron bunch going through it by Zhang {\\itshape et al.}, we study the generation of electron-induced radiation from electrons' interaction with Maxwell's fish-eye sphere. Our calculation shows that the radiation is due to a combination of \\u{C}erenkov radiation and transition radiation, which may pave the way to investigate new schemes of transferring evanescent wave to radiation.

Liu, Yangjie

2013-01-01T23:59:59.000Z

318

Technology transfer 1994  

SciTech Connect (OSTI)

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.

Not Available

1994-01-01T23:59:59.000Z

319

Heat transfer between elastic solids with randomly rough surfaces  

E-Print Network [OSTI]

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.

B. N. J. Persson; B. Lorenz; A. I. Volokitin

2009-08-27T23:59:59.000Z

320

Characterizing the hohlraum radiation via one-end driven experiments  

SciTech Connect (OSTI)

A new experiment is designed and performed on the Shenguang III laser facility with the first eight available beams to characterizing the hohlraum radiation, in which the hohlraum with laser entrance holes on both ends is driven through one-end only. The experiment enables us to identify the x-ray radiations originated from the hohlraum reemission wall and high-Z bubble plasmas utilizing their position and spectral characters, which provides a better test on the associated hohlraum models. The total and M-band x-ray radiation fluxes are measured with the flat response x-ray detectors and the filtered M-band x-ray detectors, respectively. Numerical simulations are conducted with the two-dimensional radiation hydrodynamic code LARED-INTEGRATION using the multi-group radiation transfer and/or diffusion models. It is found that the experimentally measured temporal profiles and angular distributions of hohlraum radiation are in good agreement with the predictions of simulation using radiation transfer models, but differ significantly from the results obtained with the multi-group radiation diffusion calculations. We thus note that to accurately represent the hohlraum radiation, a true radiation transfer model is essential.

Zhao, Yiqing; Zou, Shiyang, E-mail: zou-shiyang@iapacm.ac.cn [Institute of Applied Physics and Computational, Beijing 100094 (China); Li, Sanwei; Li, Zhichao; Guo, Liang [Research Center of Laser Fusion, Chinese Academy of Engineering Physics, Mianyang 621900 (China)

2014-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Heat-transfer coefficients in agitated vessels. Sensible heat models  

SciTech Connect (OSTI)

Transient models for sensible heat were developed to assess the thermal performance of agitated vessels with coils and jackets. Performance is quantified with the computation of heat-transfer coefficients by introducing vessel heating and cooling data into model equations. Of the two model categories studied, differential and macroscopic, the latter is preferred due to mathematical simplicity and lower sensitivity to experimental data variability.

Kumpinsky, E. [Ashland Chemical Co., Columbus, OH (United States). Research and Development Dept.

1995-12-01T23:59:59.000Z

322

Heat Transfer Characteristics of a Generalized Divided Flow Heat Exchanger  

E-Print Network [OSTI]

The concept of a "Divided-flow" heat exchanger is generalized by locating the shell inlet (or outlet) nozzle off-center such that the two shell sub-streams are unequal and traverse unequal flow paths. The governing equations for heat transfer...

Singh, K. P.

1979-01-01T23:59:59.000Z

323

Applications of Differential Equations  

E-Print Network [OSTI]

several techniques for solving commonly-occurring first- order and second-order ordinary differential electrical circuits, projectile motion and Newton's law of cooling recognise and solve second-order ordinary's law of cooling In section 19.1 we introduced Newton's law of cooling. The model equation was d dt = -k

Vickers, James

324

Source storage and transfer cask: Users Guide  

SciTech Connect (OSTI)

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.

Eccleston, G.W.; Speir, L.G.; Garcia, D.C.

1985-04-01T23:59:59.000Z

325

NEW SOURCES OF RADIATION  

E-Print Network [OSTI]

Stanford Synchrotron Radiation Project Report No. 75/07.IBL 79M0733 Fig. 20. Radiation emission pattern by electronsWinick, Stanford Synchrotron Radiation Laboratory. Fig. 21.

Schimmerling, W.

2010-01-01T23:59:59.000Z

326

Radiation-induced angiosarcoma  

E-Print Network [OSTI]

1a Figure 1b Figure 1. Radiation-induced angiosarcoma in afollowing completion of radiation therapy. Figure 2a Figurecell histiocytosis after radiation for breast carcinoma: can

Anzalone, C Lane; Cohen, Philip R; Diwan, Abdul H; Prieto, Victor G

2013-01-01T23:59:59.000Z

327

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...

328

Importance of Compton scattering for radiation spectra of isolated neutron stars with weak magnetic fields  

E-Print Network [OSTI]

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.

V. Suleimanov; K. Werner

2007-02-15T23:59:59.000Z

329

Technology Transfer Office November 2009  

E-Print Network [OSTI]

Technology Transfer Office November 2009 INVENTION AGREEMENT In consideration of my employment in writing to Dartmouth through the Technology Transfer Office any such discovery or invention and identify

Myers, Lawrence C.

330

Ames Lab 101: Technology Transfer  

ScienceCinema (OSTI)

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.

Covey, Debra

2012-08-29T23:59:59.000Z

331

Ames Lab 101: Technology Transfer  

SciTech Connect (OSTI)

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.

Covey, Debra

2010-01-01T23:59:59.000Z

332

VOLUNTARY LEAVE TRANSFER PROGRAM  

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

VOLUNTARY LEAVE TRANSFER PROGRAM LIST Name Organization Fairbanks, Mary H. AU Garnett-Harris, Deborah A. AU James, Debra A. AU Johnston, Robyne AU May, Melanie P. AU Pickens,...

334

E-Print Network 3.0 - absorption tissue distribution Sample Search...  

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

tomography with the frequency domain equation of radiative transfer Summary: of radiative transfer. Transport properties of tissue become significant when strong light...

335

Radiative MHD simulation of sunspot structure  

E-Print Network [OSTI]

Results of a 3D MHD simulation of a sunspot with a photospheric size of about 20 Mm are presented. The simulation has been carried out with the MURaM code, which includes a realistic equation of state with partial ionization and radiative transfer along many ray directions. The largely relaxed state of the sunspot shows a division in a central dark umbral region with bright dots and a penumbra showing bright filaments of about 2 to 3 Mm length with central dark lanes. By a process similar to the formation of umbral dots, the penumbral filaments result from magneto-convection in the form of upflow plumes, which become elongated by the presence of an inclined magnetic field: the upflow is deflected in the outward direction while the magnetic field is weakened and becomes almost horizontal in the upper part of the plume near the level of optical depth unity. A dark lane forms owing to the piling up of matter near the cusp-shaped top of the rising plume that leads to an upward bulging of the surfaces of constant optical depth. The simulated penumbral structure corresponds well to the observationally inferred interlocking-comb structure of the magnetic field with Evershed outflows along dark-laned filaments with nearly horizontal magnetic field and overturning perpendicular (`twisting') motion, which are embedded in a background of stronger and less inclined field. Photospheric spectral lines are formed at the very top and somewhat above the upflow plumes, so that they do not fully sense the strong flow as well as the large field inclination and significant field strength reduction in the upper part of the plume structures.

M. Rempel; M. Schuessler; M. Knoelker

2008-09-30T23:59:59.000Z

336

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference Las Vegas, Nevada, USA July 21-23, 2003 HT2003-47449 HEAT TRANSFER FROM A MOVING AND EVAPORATING MENISCUS ON A HEATED SURFACE meniscus with complete evaporation of water without any meniscus break-up. The experimental heat transfer

Kandlikar, Satish

337

Resources, framing, and transfer p. 1 Resources, framing, and transfer  

E-Print Network [OSTI]

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

Hammer, David

338

Thermal conductivity and heat transfer in superlattices  

SciTech Connect (OSTI)

Understanding the thermal conductivity and heat transfer processes in superlattice structures is critical for the development of thermoelectric materials and devices based on quantum structures. This work reports progress on the modeling of thermal conductivity of superlattice structures. Results from the models established based on the Boltzmann transport equation could explain existing experimental results on the thermal conductivity of semiconductor superlattices in both in plane and cross-plane directions. These results suggest the possibility of engineering the interfaces to further reduce thermal conductivity of superlattice structures.

Chen, G.; Neagu, M.; Borca-Tasciuc, T.

1997-07-01T23:59:59.000Z

339

Convective heat transfer inside passive solar buildings  

SciTech Connect (OSTI)

Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

1983-01-01T23:59:59.000Z

340

Convective heat transfer inside passive solar buildings  

SciTech Connect (OSTI)

Natural convection between spaces in a building which play a major role in energy transfer are discussed. Two situations are investigated: Convection through a single doorway into a remote room, and a convective loop in a two story house with a south sunspace where a north stairway serves as the return path. A doorway sizing equation is given for the single door case. Data from airflow monitoring in one two-story house and summary data for five others are presented. The nature of the airflow and design guidelines are presented.

Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

1983-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Stochastic equations for thermodynamics  

E-Print Network [OSTI]

The applicability of stochastic differential equations to thermodynamics is considered and a new form, different from the classical Ito and Stratonovich forms, is introduced. It is shown that the new presentation is more appropriate for the description of thermodynamic fluctuations. The range of validity of the Boltzmann-Einstein principle is also discussed and a generalized alternative is proposed. Both expressions coincide in the small fluctuation limit, providing a normal distribution density.

Tsekov, R

2015-01-01T23:59:59.000Z

342

Exact solution to the Landau-Lifshitz equation in a constant electromagnetic field  

E-Print Network [OSTI]

We are interested in the motion of a classical charge acted upon an external constant electromagnetic field where the back reaction of the particle's own field is taken into account. The Landau-Lifshitz approximation to the Lorentz-Abraham-Dirac equation is solved exactly and in closed form. It is shown that the ultrarelativistic limit of the Landau-Lifshitz equation for a radiating charge is the equation for eigenvalues and eigenvectors of the external electromagnetic field tensor.

Yurij Yaremko

2014-12-04T23:59:59.000Z

343

Technology transfer @ VUB Hugo Loosvelt  

E-Print Network [OSTI]

13/12/2012 Technology transfer @ VUB Hugo Loosvelt #12;VUB in Brussels www.vub.ac.be including or conclude licensing contracts #12;Technology transfer TTI assists academics to realise knowledge transfer by needed for R&D collaboration, licensing and spin-out company formation Technology transfer is the process

Steels, Luc

344

POSITION DESCRIPTION 2012 TRANSFER MENTOR  

E-Print Network [OSTI]

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 to CSU including (but not limited to) helping transfer students explore study skills, time management

345

Richard Bland College Transfer Guide  

E-Print Network [OSTI]

and Technology-IDT Interdisciplinary Studies-IDS International Business-INBU International Studies-IS ItalianRichard Bland College Transfer Guide #12;Using the Transfer Guide Thank you for your interest in Old Dominion University!!! The ODU Transfer Guide is designed to assist students transferring to ODU

346

Radial heat transfer from a moving plasma  

E-Print Network [OSTI]

. The plasma temperature is assumed constant axially and rad'ally and equal to the value at the exit of tl. e arc. chamber. This temperature was used in the determ'r. a- tion of the Nusselt number a, d the Reynolds number used in the above correlatior... and measured values and estimated the accuracy of the heat flux data to be within Measurements of the total continuum radiatior. or simply the energy transferred by radiation from a wall stabilized argon plasma arc were made by Barzelay (14), Comparisons...

Johnson, James Randall

1966-01-01T23:59:59.000Z

347

A novel nanometric DNA thin film as a sensor for alpha radiation  

E-Print Network [OSTI]

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

Cai, Long

348

Radiation in Yang-Mills formulation of gravity and a generalized pp-wave metric  

E-Print Network [OSTI]

The variational methods implemented on a quadratic Yang-Mills type Lagrangian yield two sets of equations interpreted as the field equations and the energy-momentum tensor for the gravitational field. A covariant condition is imposed on the energy-momentum tensor to represent the radiation field. A generalized pp-wave metric is found to simultaneously satisfy both the field equations and the radiation condition. The result is compared with that of Lichn\\'{e}rowicz.

S. Baskal

1997-12-23T23:59:59.000Z

349

Simulating corrosion-erosion mass transfer using plaster models  

SciTech Connect (OSTI)

Corrosion-erosion is a term that covers a variety of processes leading to the removal of metal in low-carbon steel piping conveying water or steam/water mixtures at a temperature of 150 {+-} 50{degree}C. One of the most important of these processes is corrosion-dissolution. This is most likely to occur where disturbances or fittings cause local high velocities and thus high mass transfer coefficients. The wear equation, which requires the local mass transfer coefficient, is presented. This paper presents a way of determining the local mass transfer coefficient. This paper reports measurements of both local and nominal mass transfer coefficients on a plaster model of a defective weld in a pipe. Welds are particularly important because they are often the place where wear is the greatest and the pipe is most severely thinned.

Griffith, P.; de Freitas, G.

1989-01-01T23:59:59.000Z

350

Syllabus for Ordinary Differential Equations  

E-Print Network [OSTI]

Syllabus for MA266, Ordinary Differential Equations. (Sections 052 & 091). GENERAL INFORMATION. Course instructor and contact information: Instructor: Dr.

Alan Demlow

2015-01-12T23:59:59.000Z

351

Radiative Transfer, Satellite Retrieval Systems and 32 Years  

E-Print Network [OSTI]

computer · 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 · 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

Kuligowski, Bob

352

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

and J.A. Lercher, Hydrogen Storage in Microspheres - FinalHydrogen Program Review Hydrogen Storage, U.S. DepartmentAn overview of hydrogen storage methods, in Hydro- gen

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

353

Journal of Quantitative Spectroscopy & Radiative Transfer 100 (2006) 457469  

E-Print Network [OSTI]

, College Station, TX 77843, USA b Remote sensing Division, Code 7232, Naval Research Laboratory, Washington

354

EXPERIMENTAL MEASUREMENT OF RADIATION HEAT TRANSFER FROM COMPLEX  

E-Print Network [OSTI]

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

355

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

by a heating lamp emitting in the visible and near infraredwith heating in a furnace at 400 o C. The infrared lamp was

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

356

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

Vie, and . Ulleberg, Hydrogen Production and Storage - R&Dfor production. The procedure for hydrogen storage and

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

357

Radiation-transparent windows, method for imaging fluid transfers  

DOE Patents [OSTI]

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.

Shu, Deming (Darien, IL); Wang, Jin (Burr Ridge, IL)

2011-07-26T23:59:59.000Z

358

Journal of Quantitative Spectroscopy & Radiative Transfer 106 (2007) 325347  

E-Print Network [OSTI]

, 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

359

Uncertainty of microwave radiative transfer computations in rain  

E-Print Network [OSTI]

retrieval using new thermodynamic observations; and 3) to investigate the characteristics of four different RT codes. Firstly, a plane-parallel RT Model (RTM) of n layers in light rainfall was used for the analytical and computational derivation...

Hong, Sung Wook

2009-06-02T23:59:59.000Z

360

Efficient wireless non-radiative mid-range energy transfer  

E-Print Network [OSTI]

-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

Soljaèiæ, Marin

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Influence of Infrared Radiation on Attic Heat Transfer  

E-Print Network [OSTI]

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...

Katipamula, S.; Turner, W. D.; Murphy, W. E.; O'Neal, D. L.

1985-01-01T23:59:59.000Z

362

Journal of Quantitative Spectroscopy & Radiative Transfer 103 (2007) 168174  

E-Print Network [OSTI]

.05.010 ?Corresponding author. Tel.: +1 303 871 2897; fax: +1 303 871 4405. E-mail addresses: agoldman@du.edu, goldman

363

Journal of Quantitative Spectroscopy & Radiative Transfer 101 (2006) 404410  

E-Print Network [OSTI]

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

364

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

samples are exposed to an incandescent lamp. Acknowledgmentin a furnace or by an incandescent lamp. It was observedwhen heated by an incandescent lamp than within furnace.

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

365

Journal of Quantitative Spectroscopy & Radiative Transfer 7980 (2003) 11711188  

E-Print Network [OSTI]

.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

Baum, Bryan A.

366

Journal of Quantitative Spectroscopy & Radiative Transfer 70 (2001) 473504  

E-Print Network [OSTI]

, and the asymmetry parameter of the phase function for ice crystals smaller than 40 m. For particles larger than­13 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

Baum, Bryan A.

367

NNSA Transfers Responsibility for Radiation Detection System to China  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challengeMultiscaleLogosAdministrationNetworkNuclearNationalTimeline

368

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD) by Microtops AtmosphericApplication andAn AssessmentARM EngineeringOnatmospheric profilesModeling

369

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for medical point07.06

370

Journal of Quantitative Spectroscopy & Radiative Transfer 98 (2006) 122129  

E-Print Network [OSTI]

and unaccounted-for solar energy sink in the atmosphere. We spectrally resolve, for the first time, all solar

Zender, Charles

371

CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160Benin: EnergyBoston Areais3: Crystalline Rock -COPPE Incubator JumpISES- 2003 CROSS

372

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

Energy, O?ce of Hydrogen, Fuel Cells and Infrastructurefuel cells, (d) the large amount of energy required to compress hydrogen

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

373

Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 285296  

E-Print Network [OSTI]

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

Fan, Tai-Hsi

374

Alpha Radiation  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICE OF RESEARCHThermal SolarAllocatioBasics of Radiation Gamma

375

Investigation of classical radiation reaction with aligned crystals  

E-Print Network [OSTI]

Classical radiation reaction is the effect of the radiation emitted by an accelerated electric charge on the trajectory of the charge itself. The self-consistent underlying classical equation of motion including radiation-reaction effects, the Landau-Lifshitz equation, has never been tested experimentally, in spite of the first theoretical treatments having been developed more than a century ago. Here, we show that classical radiation reaction effects, as predicted by the Landau-Lifshitz equation, can be measured using presently available facilities, in the energy emission spectrum of a parallel $10$-$\\text{GeV}$ electron beam crossing a $1.1$-$\\text{mm}$ thick diamond crystal in the axial channeling regime. Our theoretical results demonstrate the feasibility of the suggested setup, e.g., at the CERN Secondary Beam Areas (SBA) beamlines.

Di Piazza, A; Uggerhj, Ulrik I

2015-01-01T23:59:59.000Z

376

Approved Module Information for ME3013, 2014/5 Module Title/Name: Heat Transfer and Turbomachinery Module Code: ME3013  

E-Print Network [OSTI]

Approved Module Information for ME3013, 2014/5 Module Title/Name: Heat Transfer and Turbomachinery Outcomes: The students will have developed an understanding of a range of advanced heat transfer and turbo-machinery. * Unsteady heat transfer Turbomachinery: * Momentum and energy equations for turbo-machines * Radial, axial

Neirotti, Juan Pablo

377

Heat Transfer -2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature  

E-Print Network [OSTI]

Heat Transfer - 2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature T = 10o C. The heat transfer coefficient at the wire's surface h equation that includes all heat transfer mechanisms involved in this problem. Write this energy balance

Virginia Tech

378

Radiation fields for nanoscale systems Ming Liang Zhang* and D. A. Drabold**  

E-Print Network [OSTI]

Radiation fields for nanoscale systems Ming Liang Zhang* and D. A. Drabold** Department of Physics-classical radiation theory, temporal coarse graining * Corresponding author: e-mail zhangm@ohio.edu, Phone: (01) 740 semi-classical radiation theory (SCRT) with these sources, the microscopic Maxwell equations can

Drabold, David

379

Radiation Pressure in Massive Star Formation  

E-Print Network [OSTI]

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.

Mark R. Krumholz; Richard I. Klein; Christopher F. McKee

2005-10-14T23:59:59.000Z

380

Application of Improved Radiation Modeling to General Circulation Models  

SciTech Connect (OSTI)

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.

Michael J Iacono

2011-04-07T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

DRY TRANSFER FACILITY WORKER DOSE ASSESSMENT  

SciTech Connect (OSTI)

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.

J.S. Tang

2004-09-23T23:59:59.000Z

382

Adaptors for radiation detectors  

DOE Patents [OSTI]

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.

Livesay, Ronald Jason

2014-04-22T23:59:59.000Z

383

Hawking radiation in moving plasmas  

E-Print Network [OSTI]

Bi-metricity and Hawking radiation are exhibit in non-relativistic moving magnetohydrodynamics (MHD) plasma medium generating two Riemannian effective spacetimes. The first metric is a flat metric although the speed of "light" is given by a time dependent signal where no Hawking radiation or effective black holes are displayed. This metric comes from a wave equation which the scalar function comes from the scalar potential of the background velocity of the fluid and depends on the perturbation of the magnetic background field. The second metric is an effective spacetime metric which comes from the perturbation of the background MHD fluid. This Riemann metric exhibits a horizon and Hawking radiation which can be expressed in terms of the background constant magnetic field. The effective velocity is given Alfven wave velocity of plasma physics. The effective black hole found here is analogous to the optical black hole in moving dielectrics found by De Lorenci et al [Phys. Rev. D (2003)] where bi-metricity and Hawking radiation in terms of the electric field are found.

L. C. Garcia de Andrade

2005-09-07T23:59:59.000Z

384

Radiation detector system having heat pipe based cooling  

DOE Patents [OSTI]

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.

Iwanczyk, Jan S.; Saveliev, Valeri D.; Barkan, Shaul

2006-10-31T23:59:59.000Z

385

Urban Sewage Delivery Heat Transfer System (2): Heat Transfer  

E-Print Network [OSTI]

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...

Zhang, C.; Wu, R.; Li, X.; Li, G.; Zhuang, Z.; Sun, D.

2006-01-01T23:59:59.000Z

386

A Master Equation Approach to the `3 + 1' Dirac Equation  

E-Print Network [OSTI]

A derivation of the Dirac equation in `3+1' dimensions is presented based on a master equation approach originally developed for the `1+1' problem by McKeon and Ord. The method of derivation presented here suggests a mechanism by which the work of Knuth and Bahrenyi on causal sets may be extended to a derivation of the Dirac equation in the context of an inference problem.

Keith A. Earle

2011-02-06T23:59:59.000Z

387

Analysis of multi-stage centrifugal pumps using transfer matrices  

E-Print Network [OSTI]

around the x-axis. The transfer across the massless beam number n is obtained in the same manner. PE?'?= 0-. V???? V?'?= 0 Q M4, ? 0 ~ My?, ? M~ ? V' l?= 0 (2) Rearranging the terms of equations 1 and 2 results in equations 3. M, ' = V, ?? r, ? V...~ Bearing Shaft Y' QB Figure 6. Schematic of bearing forces acting on shaft with eccentricity and attitude angle. 1. 0 0. 0 O M M CI M W lJ w 0. 4 I-I 0. 2 'Ilj . i I' I', ' r 'I I jij !Ij l Il t I . 'll t!!I tR 'Iles 'I I! i...

Kelly, J. Howard

1989-01-01T23:59:59.000Z

388

The Schroedinger equation with friction from the quantum trajectory perspective  

SciTech Connect (OSTI)

Similarity of equations of motion for the classical and quantum trajectories is used to introduce a friction term dependent on the wavefunction phase into the time-dependent Schroedinger equation. The term describes irreversible energy loss by the quantum system. The force of friction is proportional to the velocity of a quantum trajectory. The resulting Schroedinger equation is nonlinear, conserves wavefunction normalization, and evolves an arbitrary wavefunction into the ground state of the system (of appropriate symmetry if applicable). Decrease in energy is proportional to the average kinetic energy of the quantum trajectory ensemble. Dynamics in the high friction regime is suitable for simple models of reactions proceeding with energy transfer from the system to the environment. Examples of dynamics are given for single and symmetric and asymmetric double well potentials.

Garashchuk, Sophya; Dixit, Vaibhav; Gu Bing; Mazzuca, James [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208 (United States)

2013-02-07T23:59:59.000Z

389

Faculty Positions Heat Transfer and  

E-Print Network [OSTI]

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

390

RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND  

E-Print Network [OSTI]

RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND RADIATION SAFETY MANUAL UNIVERSITY OF MARYLAND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2. Radiation Safety Committee (RSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.4. Radiation Safety Office (RSO

Rubloff, Gary W.

391

Plastic container bagless transfer  

DOE Patents [OSTI]

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.

Tibrea, Steven L.; D'Amelio, Joseph A.; Daugherty, Brent A.

2003-11-18T23:59:59.000Z

392

Technology Transfer Ombudsman Program | Department of Energy  

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

Technology Transfer Ombudsman Program Technology Transfer Ombudsman Program The Technology Transfer Commercialization Act of 2000, Public Law 106-404 (PDF) was enacted in November...

393

Scattering of particles by radiation fields: a comparative analysis  

E-Print Network [OSTI]

The features of the scattering of massive neutral particles propagating in the field of a gravitational plane wave are compared with those characterizing their interaction with an electromagnetic radiation field. The motion is geodesic in the former case, whereas in the case of an electromagnetic pulse it is accelerated by the radiation field filling the associated spacetime region. The interaction with the radiation field is modeled by a force term entering the equations of motion proportional to the 4-momentum density of radiation observed in the particle's rest frame. The corresponding classical scattering cross sections are evaluated too.

Donato Bini; Andrea Geralico; Maria Haney; Robert T. Jantzen

2014-08-22T23:59:59.000Z

394

Aachen Institute for Advanced Study in Computational Engineering Science Preprint: AICES-2010/12-2  

E-Print Network [OSTI]

. Introduction The radiative transfer equation is a basic model for the transport of non-interacting particles09. Key words and phrases. linear Boltzmann equation, neutron transport equation, radiative transfer/12-2 16/December/2010 A Mixed Variational Framework for the Radiative Transfer Equation H. Egger and M

Rheinisch-Westfälische Technische Hochschule Aachen (RWTH)

395

Field Equations and Conservation Laws in the Nonsymmetric Gravitational Theory  

E-Print Network [OSTI]

The field equations in the nonsymmetric gravitational theory are derived from a Lagrangian density using a first-order formalism. Using the general covariance of the Lagrangian density, conservation laws and tensor identities are derived. Among these are the generalized Bianchi identities and the law of energy-momentum conservation. The Lagrangian density is expanded to second-order, and treated as an ``Einstein plus fields'' theory. From this, it is deduced that the energy is positive in the radiation zone.

J. Legare; J. W. Moffat

1994-12-08T23:59:59.000Z

396

On the harmonic map equation  

E-Print Network [OSTI]

A generalized harmonic map equation is presented based on the proposed action functional in the Weyl space (PLA, 135, 315, 1989).

S. C. Tiwari

2007-06-09T23:59:59.000Z

397

Radiation Control (Virginia)  

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...

398

A phase-field method for 3D simulation of two-phase heat transfer , H. Babaee a  

E-Print Network [OSTI]

the efficiency of the new method in simulating 3D multi-phase convective heat transfer on stationary gridsA phase-field method for 3D simulation of two-phase heat transfer X. Zheng a , H. Babaee a , S Keywords: Spectral element Non-moving grid Cahn­Hilliard equation Large thermal conductivity ratio a b

Dong, Suchuan "Steven"

399

Energy of gravitational radiation in plane-symmetric space-times  

E-Print Network [OSTI]

Gravitational radiation in plane-symmetric space-times can be encoded in a complex potential, satisfying a non-linear wave equation. An effective energy tensor for the radiation is given, taking a scalar-field form in terms of the potential, entering the field equations in the same way as the matter energy tensor. It reduces to the Isaacson energy tensor in the linearized, high-frequency approximation. An energy conservation equation is derived for a quasi-local energy, essentially the Hawking energy. A transverse pressure exerted by interacting low-frequency gravitational radiation is predicted.

Sean A. Hayward

2008-05-19T23:59:59.000Z

400

Scattering by an electromagnetic radiation field  

E-Print Network [OSTI]

Motion of test particles in the gravitational field associated with an electromagnetic plane wave is investigated. The interaction with the radiation field is modeled by a force term {\\it \\`a la} Poynting-Robertson entering the equations of motion given by the 4-momentum density of radiation observed in the particle's rest frame with a multiplicative constant factor expressing the strength of the interaction itself. Explicit analytical solutions are obtained. Scattering of fields by the electromagnetic wave, i.e., scalar (spin 0), massless spin $\\frac12$ and electromagnetic (spin 1) fields, is studied too.

Donato Bini; Andrea Geralico

2014-08-21T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

A Theoretical Investigation Into Energy Transfer In Photosynthetic Open Quantum Systems  

E-Print Network [OSTI]

This thesis looks at the electronic energy transfer in the Fenna-Matthews-Olson complex, in which evidence of long-lived coherence has been observed in 2-dimensional infrared experiments. I use three techniques: the numerically exact Hierarchical Equations of Motion, and the perturbative Redfield and Foerster theories, the latter of which ignores quantum coherence in the transfer. Both of the approximate methods perform very well - and while oscillations in site populations (a hallmark of coherence) are present in the exact transfer dynamics and absent in the dynamics of Foerster theory, the latter gives a reasonable prediction of transfer rates and steady-state populations, despite being incoherent - suggesting that coherence is not vital for the dynamics of transfer. Since Foerster theory is very inexpensive to run and performs so well, I then apply it to calculate the effects of static disorder in bacteriochlorophyll site energies and of a more structured spectral density. Ultimately, the energy transfer i...

Wilkins, David M

2015-01-01T23:59:59.000Z

402

Wireless Power Transfer  

SciTech Connect (OSTI)

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

403

Wireless Power Transfer  

ScienceCinema (OSTI)

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

2013-11-19T23:59:59.000Z

404

Effective equations for quantum dynamics  

E-Print Network [OSTI]

We report on recent results concerning the derivation of effective evolution equations starting from many body quantum dynamics. In particular, we obtain rigorous derivations of nonlinear Hartree equations in the bosonic mean field limit, with precise bounds on the rate of convergence. Moreover, we present a central limit theorem for the fluctuations around the Hartree dynamics.

Benjamin Schlein

2012-08-01T23:59:59.000Z

405

Data Transfer Examples  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to UserProduct: CrudeOffice ofINL is aID Service First DOIData Transfer»

406

Transfers | Department of Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up from theDepartment of EnergyThe Sun andDepartment ofFanTransactive1/08Transfers

407

Transfer reactions at ATLAS  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2Topo II: AnTraining andfor a CleanTransfer Service

408

NREL: Technology Transfer - Ombuds  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions andData and ResourcesOther FederalNicheTechnology Transfer Ombuds

409

Radiation transport and density effects in non-equilibrium plasmas Vladimir I. Fisher*, Dimitri V. Fisher, Yitzhak Maron  

E-Print Network [OSTI]

Radiation transport and density effects in non-equilibrium plasmas Vladimir I. Fisher*, Dimitri V populations and the radiation field in transient non-equilibrium plasmas. In this model, the plasma density to a self-consistent treatment of the radiative transfer. For non-Maxwellian plasmas, the atomic

410

Fourier analysis of conductive heat transfer for glazed roofing materials  

SciTech Connect (OSTI)

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.

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

411

Study of cloud properties from single-scattering, radiative forcing, and retrieval perspectives  

E-Print Network [OSTI]

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...

Lee, Yong-Keun

2009-06-02T23:59:59.000Z

412

of MATHEMATICS AcademyofSciences  

E-Print Network [OSTI]

by the radiative transfer equation: a linear transport equation with a (non linear) source term and the fluid-radiation-Stokes- Fourier system coupled to a stationary radiative transfer equation. 1 Introduction We revisit a model interaction appears through radiative sources in the momentum and energy equations.The system under study

Krejcí, Pavel

413

Polarization transfer NMR imaging  

DOE Patents [OSTI]

A nuclear magnetic resonance (NMR) image is obtained with spatial information modulated by chemical information. The modulation is obtained through polarization transfer from a first element representing the desired chemical, or functional, information, which is covalently bonded and spin-spin coupled with a second element effective to provide the imaging data. First and second rf pulses are provided at first and second frequencies for exciting the imaging and functional elements, with imaging gradients applied therebetween to spatially separate the nuclei response for imaging. The second rf pulse is applied at a time after the first pulse which is the inverse of the spin coupling constant to select the transfer element nuclei which are spin coupled to the functional element nuclei for imaging. In a particular application, compounds such as glucose, lactate, or lactose, can be labeled with .sup.13 C and metabolic processes involving the compounds can be imaged with the sensitivity of .sup.1 H and the selectivity of .sup.13 C.

Sillerud, Laurel O. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM)

1990-01-01T23:59:59.000Z

414

Self-force via energy-momentum and angular momentum balance equations  

E-Print Network [OSTI]

The radiation reaction for a point-like charge coupled to a massive scalar field is considered. The retarded Green's function associated with the Klein-Gordon wave equation has support not only on the future light cone of the emission point (direct part), but extends inside the light cone as well (tail part). Dirac's scheme of decomposition of the retarded electromagnetic field into the "mean of the advanced and retarded field" and the "radiation" field is adapted to theories where Green's function consists of the direct and the tail parts. The Harish-Chandra equation of motion of radiating scalar charge under the influence of an external force is obtained. This equation includes effect of particle's own field. The self force produces a time-changing inertial mass.

Yurij Yaremko

2012-07-20T23:59:59.000Z

415

Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site  

SciTech Connect (OSTI)

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.

Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.

1992-03-01T23:59:59.000Z

416

Photon rockets and gravitational radiation  

E-Print Network [OSTI]

The absence of gravitational radiation in Kinnersley's ``photon rocket'' solution of Einstein's equations is clarified by studying the mathematically well-defined problem of point-like photon rockets in Minkowski space (i.e. massive particles emitting null fluid anisotro\\-pically and accelerating because of the recoil). We explicitly compute the (uniquely defined) {\\it linearized} retarded gravitational waves emitted by such objects, which are the coherent superposition of the gravitational waves generated by the motion of the massive point-like rocket and of those generated by the energy-momentum distribution of the photon fluid. In the special case (corresponding to Kinnersley's solution) where the anisotropy of the photon emission is purely dipolar we find that the gravitational wave amplitude generated by the energy-momentum of the photons exactly cancels the usual $1/r$ gravitational wave amplitude generated by the accelerated motion of the rocket. More general photon anisotropies would, however, generate genuine gravitational radiation at infinity. Our explicit calculations show the compatibility between the non-radiative character of Kinnersley's solution and the currently used gravitational wave generation formalisms based on post-Minkowskian perturbation theory.

T. Damour

1994-12-21T23:59:59.000Z

417

A 2-D Test Problem for CFD Modeling Heat Transfer in Spent Fuel Transfer Cask Neutron Shields  

SciTech Connect (OSTI)

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

Zigh, Ghani; Solis, Jorge; Fort, James A.

2011-01-14T23:59:59.000Z

418

Comparisons Between Different Forward Models For Light Transport In Tissues  

E-Print Network [OSTI]

The radiative transfer equation to describe the laser radiation transport in scattering, absorbing and emitting the radiative heat transfer equation, which can be applied to almost all the electromagnetic radiation. The diffusion approximation method is controlled by a differential equation, which is derived from radiative

Guo, Zhixiong "James"

419

On the multi-physics of mass-transfer across fluid interfaces  

E-Print Network [OSTI]

Mass transfer of gaseous components from rising bubbles to the ambient liquid can be described based on continuum mechanical sharp-interface balances of mass, momentum and species mass. In this context, the standard model consists of the two-phase Navier-Stokes equations for incompressible fluids with constant surface tension, complemented by reaction-advection-diffusion equations for all constituents, employing Fick's law. This standard model is inconsistent with the continuity equation, the momentum balance and the second law of thermodynamics. The present paper reports on the details of these severe shortcomings and provides thermodynamically consistent model extensions which are required to capture various phenomena which occur due to the multi-physics of interfacial mass transfer. In particular, we provide a simple derivation of the interface Maxwell-Stefan equations which does not require a time scale separation, while the main contribution is to show how interface concentrations and interface chemical ...

Bothe, Dieter

2015-01-01T23:59:59.000Z

420

Galaxy formation with radiative and chemical feedback  

E-Print Network [OSTI]

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...

Graziani, L; Schneider, R; Kawata, D; de Bennassuti, M; Maselli, A

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Tropical Cloud Properties and Radiative Heating Profiles  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

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.

Mather, James

422

Solar2014: The 52nd Annual Conference of the Australian Solar Council 1 Open cavity receiver geometry influence on radiative losses  

E-Print Network [OSTI]

, Radiative transfer, Ray tracing. Abstract Open cavity receivers can be used to efficiently absorb concentrated solar radiation and transfers this heat to a Heat Carrier (HC). Recent advances in CSPSolar2014: The 52nd Annual Conference of the Australian Solar Council 1 Open cavity receiver

423

INTRODUCTORY LABORATORY 0: DETERMINING AN EQUATION FOR  

E-Print Network [OSTI]

below are designed to help. Once you are satisfied with an equation, press "Accept Fit Function determine the equations that best represent (fit) the measured data, and compare the resulting Fit Equations with your Prediction Equations. This activity will familiarize you with the procedure for fitting equations

Minnesota, University of

424

Heat transfer probe  

DOE Patents [OSTI]

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.

Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff

2006-10-10T23:59:59.000Z

425

Technology transfer 1995  

SciTech Connect (OSTI)

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.

Not Available

1995-01-01T23:59:59.000Z

426

University of Iowa Carver College of Medicine Baccalaureate Degree, Radiation Sciences  

E-Print Network [OSTI]

, Radiation Sciences Interest · Follow applicable instructions for First-Year , Transfer, or International applicable instructions for Transfer or International Students · Apply to and rank order the following.medicine.uiowa.edu/radsci PH: 319-353-8388 Radiologic Technology Tracks Admission and Degree Requirements Admission

427

Development of a radiative transport based, fluorescence-enhanced, frequency-domain small animal imaging system  

E-Print Network [OSTI]

% intralipid solutions. Through collaboration with Transpire, Inc., a fluorescence-enhanced, frequency-domain, radiative transport equation (RTE) solver was developed. This solver incorporates the discrete ordinates, source iteration with diffusion synthetic...

Rasmussen, John C.

2009-05-15T23:59:59.000Z

428

Partial Differential Equations of Physics  

E-Print Network [OSTI]

Apparently, all partial differential equations that describe physical phenomena in space-time can be cast into a universal quasilinear, first-order form. In this paper, we do two things. First, we describe some broad features of systems of differential equations so formulated. Examples of such features include hyperbolicity of the equations, constraints and their roles (e.g., in connection with the initial-value formulation), how diffeomorphism freedom is manifest, and how interactions between systems arise and operate. Second, we give a number of examples that illustrate how the equations for physical systems are cast into this form. These examples suggest that the first-order, quasilinear form for a system is often not only the simplest mathematically, but also the most transparent physically.

Robert Geroch

1996-02-27T23:59:59.000Z

429

Entropic corrections to Einstein equations  

SciTech Connect (OSTI)

Considering the general quantum corrections to the area law of black hole entropy and adopting the viewpoint that gravity interprets as an entropic force, we derive the modified forms of Modified Newtonian dynamics (MOND) theory of gravitation and Einstein field equations. As two special cases we study the logarithmic and power-law corrections to entropy and find the explicit form of the obtained modified equations.

Hendi, S. H. [Physics Department, College of Sciences, Yasouj University, Yasouj 75914 (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Sheykhi, A. [Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Department of Physics, Shahid Bahonar University, P.O. Box 76175-132, Kerman (Iran, Islamic Republic of)

2011-04-15T23:59:59.000Z

430

A Two Level Finite Difference Scheme for One Dimensional Pennes' Bioheat Equation \\Lambda  

E-Print Network [OSTI]

by exposing human body to heat in a flash fire or being in contact with hot substances are some of the most for a skin heating model are conducted. Key words: bioheat transfer, Pennes' equation, finite difference.S. Department of Energy Office of Science under grant DE­FG02­02ER45961, by the Japanese Research Organization

Zhang, Jun

431

Modeling for isothermal cavitation with a four-equation model Eric Goncalv`es  

E-Print Network [OSTI]

Modeling for isothermal cavitation with a four-equation model Eric Goncalv`es , Boris Charri-dimensional inviscid cavitating tube problems. This mass transfer term appears explicitly as a source term of a void realistic cavitating flows. Numerical results are given for various inviscid cases (underwater explosion

Paris-Sud XI, Université de

432

How accurate is Limber's equation?  

E-Print Network [OSTI]

The so-called Limber equation is widely used in the literature to relate the projected angular clustering of galaxies to the spatial clustering of galaxies in an approximate way. This paper gives estimates of where the regime of applicability of Limber's equation stops. Limber's equation is accurate for small galaxy separations but breaks down beyond a certain separation that depends mainly on the ratio sigma/R and to some degree on the power-law index, gamma, of spatial clustering xi; sigma is the one-sigma width of the galaxy distribution in comoving distance, and R the mean comoving distance. As rule-of-thumb, a 10% relative error is reached at 260 sigma/R arcmin for gamma~1.6, if the spatial clustering is a power-law. More realistic xi are discussed in the paper. Limber's equation becomes increasingly inaccurate for larger angular separations. Ignoring this effect and blindly applying Limber's equation can possibly bias results for the inferred spatial correlation. It is suggested to use in cases of doubt, or maybe even in general, the exact equation that can easily be integrated numerically in the form given in the paper.

P. Simon

2007-08-24T23:59:59.000Z

433

Plutonium radiation surrogate  

DOE Patents [OSTI]

A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

Frank, Michael I. (Dublin, CA)

2010-02-02T23:59:59.000Z

434

Time-resolved energy transfer from single chloride-terminated nanocrystals to graphene  

SciTech Connect (OSTI)

We examine the time-resolved resonance energy transfer of excitons from single n-butyl amine-bound, chloride-terminated nanocrystals to two-dimensional graphene through time-correlated single photon counting. The radiative biexponential lifetime kinetics and blinking statistics of the individual surface-modified nanocrystal elucidate the non-radiative decay channels. Blinking modification as well as a 4 reduction in spontaneous emission were observed with the short chloride and n-butylamine ligands, probing the energy transfer pathways for the development of graphene-nanocrystal nanophotonic devices.

Ajayi, O. A., E-mail: oaa2114@columbia.edu, E-mail: cww2104@columbia.edu; Wong, C. W., E-mail: oaa2114@columbia.edu, E-mail: cww2104@columbia.edu [Optical Nanostructures Laboratory, Center for Integrated Science and Engineering, Solid-State Science and Engineering, Columbia University, New York, New York 10027 (United States); Department of Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Anderson, N. C.; Wolcott, A.; Owen, J. S. [Department of Chemistry, Columbia University, New York, New York 10027 (United States); Cotlet, M. [Brookhaven National Laboratory, Upton, New York, New York 11973 (United States); Petrone, N.; Hone, J. [Department of Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Gu, T.; Gesuele, F. [Optical Nanostructures Laboratory, Center for Integrated Science and Engineering, Solid-State Science and Engineering, Columbia University, New York, New York 10027 (United States)

2014-04-28T23:59:59.000Z

435

Evaluation of GCM Column Radiation Models Under Cloudy Conditions with The Arm BBHRP Value Added Product  

SciTech Connect (OSTI)

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.

Dr. Lazaros Oreopoulos and Dr. Peter M. Norris

2010-03-14T23:59:59.000Z

436

Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger  

DOE Patents [OSTI]

A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.

Im, Kwan H. (Naperville, IL); Ahluwalia, Rajesh K. (Burr Ridge, IL)

1994-01-01T23:59:59.000Z

437

Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger  

DOE Patents [OSTI]

A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.

Im, K.H.; Ahluwalia, R.K.

1994-10-18T23:59:59.000Z

438

Turbulence radiation interaction in Reynolds-averaged Navier-Stokes simulations of nonpremixed piloted turbulent laboratory-scale flames  

SciTech Connect (OSTI)

Numerical simulation results are presented for two axisymmetric, nonluminous turbulent piloted jet diffusion flames: Sandia Flame D (SFD) and Delft Flame III (DFIII). Turbulence is represented by a Reynolds stress transport model, while chemistry is modeled by means of steady laminar flamelets. We use the preassumed PDF approach for turbulence-chemistry interaction. A weighted sum of gray gases model is used for the gas radiative properties. The radiative transfer equation is solved using the discrete ordinates method in the conservative finite-volume formulation. The radiative loss leads to a decrease in mean temperature, but does not significantly influence the flow and mixing fields, in terms either of mean values or of rms values of fluctuations. A systematic analysis of turbulence-radiation interaction (TRI) is carried out. By considering five different TRI formulations, and comparing also with a simple optically thin model, individual TRI contributions are isolated and quantified. For both flames, effects are demonstrated of (1) influence of temperature fluctuations on the mean Planck function, (2) temperature and composition fluctuations on the mean absorption coefficient, and (3) correlation between absorption coefficient and Planck function. The strength of the last effect is stronger in DFIII than in SFD, because of stronger turbulence-chemistry interaction and lower mean temperature in DFIII. The impact of the choice of TRI model on the prediction of the temperature-sensitive minor species NO is determined in a postprocessing step with fixed flow and mixing fields. Best agreement for NO is obtained using the most complete representation of TRI. (author)

Habibi, A.; Merci, B. [Department of Flow, Heat and Combustion Mechanics, Ghent University, B-9000 Ghent (Belgium); Roekaerts, D. [Delft University of Technology, Delft (Netherlands)

2007-10-15T23:59:59.000Z

439

Effect of translucence of engineering ceramics on heat transfer in diesel engines  

SciTech Connect (OSTI)

This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

Wahiduzzaman, S.; Morel, T. (Integral Technologies, Inc., Westmont, IL (United States))

1992-04-01T23:59:59.000Z

440

Effect of translucence of engineering ceramics on heat transfer in diesel engines. Final report  

SciTech Connect (OSTI)

This report describes the experimental portion of a broader study undertaken to assess the effects of translucence of ceramic materials used as thermal barrier coatings in diesel engines. In an earlier analytical work a parametric study was performed, varying several radiative properties over ranges typical of engineering ceramics, thereby identifying the most important radiative properties and their impact on in-cylinder heat transfer. In the current study these properties were experimentally determined for several specific zirconia coatings considered for thermal barrier applications in diesel engines. The methodology of this study involved formulation of a model capable of describing radiative transfer through a semitransparent medium as a function of three independent model parameters, ie, absorption coefficient, scattering coefficient and refractive index. For the zirconia-based ceramics investigated in this study, it was concluded that for usual coating thicknesses (1.5--2.5 mm) these ceramics are optically thick and hence, are effective as radiative heat transfer barriers. These ceramics possess high scattering coefficients and low absorption coefficients causing them to be highly reflective (60-80%) in the spectral region where thermal radiation is important. The performance of the investigated ceramics and the mechanism of heat transfer were found to depend on surface condition, specifically on soot deposition. Thus, to insure the optimum thermal barrier operation for either clean or heavily sooted surfaces, a ceramic material with high scattering coefficient provides the best choice.

Wahiduzzaman, S.; Morel, T. [Integral Technologies, Inc., Westmont, IL (United States)

1992-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

X-ray micromodulated luminescence tomography in dual-cone ...  

E-Print Network [OSTI]

Jul 16, 2014 ... Keywords: nanophosphor imaging; radiative transfer equation; image reconstruction; .... employed to describe the NIR light transport process.

2014-07-01T23:59:59.000Z

442

Monte Carlo Simulation of Radiation in Gases with a NarrowBand Model  

E-Print Network [OSTI]

, France (\\Phi) now at the Institute of Energy and Power Plant Technology, TH Darmstadt, 64287 DarmstadtMonte Carlo Simulation of Radiation in Gases with a Narrow­Band Model and a Net is used for simulation of radiative heat transfers in non­gray gases. The proposed procedure is based

Dufresne, Jean-Louis

443

Optical Properties and Radiation-Enhanced Evaporation of Nanofluid Fuels Containing Carbon-Based Nanostructures  

E-Print Network [OSTI]

and thermal systems as an advanced heat-transfer fluid, e.g., advanced cooling of electronics systemsOptical Properties and Radiation-Enhanced Evaporation of Nanofluid Fuels Containing Carbon characteristics of nanofluid fuels with stable suspension of carbon-based nanostructures under radiation

Qiao, Li

444

On the approximation of local and linear radiative damping in the middle  

E-Print Network [OSTI]

atmosphere. In general, this damping is a nonlocal process in which heat is transferred to and from remote form 13 November 2009) ABSTRACT The validity of approximating radiative heating rates in the middle'') is investigated. Using radiative heating rate and temperature output from a chemistry­climate model with realistic

Wirosoetisno, Djoko

445

Tachyons and Gravitational Cherenkov Radiation  

E-Print Network [OSTI]

AND GRAVITATIONAL CHERENKOV RADIATION CHARLES SCHWARTZwould emit gravitational radiation. It is very small.gravitational waves; Cherenkov radiation. In a recent work,

Schwartz, Charles

2011-01-01T23:59:59.000Z

446

Radiation Safety Program Annual Review  

E-Print Network [OSTI]

........................................................................10 AREA RADIATION SURVEYS AND CONTAMINATION CONTROL...........................................11.....................................................................................................13 RADIOACTIVE WASTE MANAGEMENT meetings of the Radiation Safety Committee where new users and uses of radioactive materials, radiation

Lyubomirsky, Ilya

447

WI Radiation Protection  

Broader source: Energy.gov [DOE]

This statute seeks to regulate radioactive materials, to encourage the constructive uses of radiation, and to prohibit and prevent exposure to radiation in amounts which are or may be detrimental...

448

Maryland Radiation Act (Maryland)  

Broader source: Energy.gov [DOE]

The policy of the state is to provide for the constructive use of radiation and control radiation emissions. This legislation authorizes the Department of the Environment to develop comprehensive...

449

THE UNLV FOUNDATION MONETARY TRANSFER FORM  

E-Print Network [OSTI]

THE UNLV FOUNDATION MONETARY TRANSFER FORM (Use one form for each account) Date Department Amount Transfer from Foundation Account Name UNLV Foundation Foundation Account Number Transfer to University contributions to this fund were accepted. Multiple Transfer A monetary transfer from the UNLV Foundation

Hemmers, Oliver

450

Proton-Coupled Electron Transfer  

SciTech Connect (OSTI)

Proton-Coupled Electron Transfer (PCET) describes reactions in which there is a change in both electron and proton content between reactants and products. It originates from the influence of changes in electron content on acid?base properties and provides a molecular-level basis for energy transduction between proton transfer and electron transfer. Coupled electron?proton transfer or EPT is defined as an elementary step in which electrons and protons transfer from different orbitals on the donor to different orbitals on the acceptor. There is (usually) a clear distinction between EPT and H-atom transfer (HAT) or hydride transfer, in which the transferring electrons and proton come from the same bond. Hybrid mechanisms exist in which the elementary steps are different for the reaction partners. EPT pathways such as PhO/PhOH exchange have much in common with HAT pathways in that electronic coupling is significant, comparable to the reorganization energy with H{sub DA} ~ ?. Multiple-Site Electron?Proton Transfer (MS-EPT) is an elementary step in which an electron?proton donor transfers electrons and protons to different acceptors, or an electron?proton acceptor accepts electrons and protons from different donors. It exploits the long-range nature of electron transfer while providing for the short-range nature of proton transfer. A variety of EPT pathways exist, creating a taxonomy based on what is transferred, e.g., 1e{sup -}/2H{sup +} MS-EPT. PCET achieves redox potential leveling between sequential couples and the buildup of multiple redox equivalents, which is of importance in multielectron catalysis. There are many examples of PCET and pH-dependent redox behavior in metal complexes, in organic and biological molecules, in excited states, and on surfaces. Changes in pH can be used to induce electron transfer through films and over long distances in molecules. Changes in pH, induced by local electron transfer, create pH gradients and a driving force for long-range proton transfer in Photosysem II and through other biological membranes. In EPT, simultaneous transfer of electrons and protons occurs on time scales short compared to the periods of coupled vibrations and solvent modes. A theory for EPT has been developed which rationalizes rate constants and activation barriers, includes temperature- and driving force (?G)-dependences implicitly, and explains kinetic isotope effects. The distance-dependence of EPT is dominated by the short-range nature of proton transfer, with electron transfer being far less demanding.Changes in external pH do not affect an EPT elementary step. Solvent molecules or buffer components can act as proton donor acceptors, but individual H2O molecules are neither good bases (pK{sub a}(H{sub 3}O{sup +}) = ?1.74) nor good acids (pK{sub a}(H{sub 2}O) = 15.7). There are many examples of mechanisms in chemistry, in biology, on surfaces, and in the gas phase which utilize EPT. PCET and EPT play critical roles in the oxygen evolving complex (OEC) of Photosystem II and other biological reactions by decreasing driving force and avoiding high-energy intermediates.

Weinberg, Dave; Gagliardi, Christopher J.; Hull, Jonathan F; Murphy, Christine Fecenko; Kent, Caleb A.; Westlake, Brittany C.; Paul, Amit; Ess, Daniel H; McCafferty, Dewey Granville; Meyer, Thomas J

2012-01-01T23:59:59.000Z

451

RADIONUCLIDE RADIATION PROTECTION  

E-Print Network [OSTI]

COPYRIGHT 2002 Nuclear Technology Publishing #12;3 #12;4 #12;5 Radiation Protection Dosimetry Vol. 98, No'Energie Atomique, CEA/Saclay, France ISBN 1 870965 87 6 RADIATION PROTECTION DOSIMETRY Vol. 98 No 1, 2002 Published by Nuclear Technology Publishing #12;RADIONUCLIDE AND RADIATION PROTECTION DATA HANDBOOK 2nd Edition (2002

Healy, Kevin Edward

452

Radiation Damping with Inhomogeneous  

E-Print Network [OSTI]

Radiation Damping with Inhomogeneous Broadening: Limitations of the Single Bloch Vector Model of inhomoge- neous broadening on radiation damping of free precession signals have been described using 13: 1 7, 2001 KEY WORDS: radiation damping; FID shape; inhomogeneous broadening The phenomenon

Augustine, Mathew P.

453

Radiation Processing -an overview  

E-Print Network [OSTI]

of radiation · Facilities ­ Gamma ­ electrons ­ X-ray ­ Safety · Sterilisation of medical devices · Food irradiation · Material modification #12;3 Content ­ Part 2 · Environmental applications · Other applications Radiation · Energy in the form of waves or moving subatomic particles Irradiation · Exposure to radiation

454

Study of intermediates from transition metal excited-state electron-transfer reactions  

SciTech Connect (OSTI)

Conventional and fast-kinetics techniques of photochemistry, photophysics, radiation chemistry, and electrochemistry were used to study the intermediates involved in transition metal excited-state electron-transfer reactions. These intermediates were excited state of Ru(II) and Cr(III) photosensitizers, their reduced forms, and species formed in reactions of redox quenchers and electron-transfer agents. Of particular concern was the back electron-transfer reaction between the geminate pair formed in the redox quenching of the photosensitizers, and the dependence of its rate on solution medium and temperature in competition with transformation and cage escape processes. (DLC)

Hoffman, M.Z.

1992-07-31T23:59:59.000Z

455

The electromagnetic fields and the radiation of a spatio-temporally varying electric current loop  

E-Print Network [OSTI]

The electric and magnetic fields of a spatio-temporally varying electric current loop are calculated using the Jefimenko equations. The radiation and the nonradiation parts of the electromagnetic fields are derived in the framework of Maxwell's theory of electromagnetic fields. In this way, a new, exact, analytical solution of the Maxwell equation is found.

Markus Lazar

2013-04-12T23:59:59.000Z

456

Pure-radiation gravitational fields with a simple twist and a Killing vector  

E-Print Network [OSTI]

Pure-radiation solutions are found, exploiting the analogy with the Euler- Darboux equation for aligned colliding plane waves and the Euler-Tricomi equation in hydrodynamics of two-dimensional flow. They do not depend on one of the spacelike coordinates and comprise the Hauser solution as a special subcase.

B. V. Ivanov

2001-03-27T23:59:59.000Z

457

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus_minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured [0 to 8.5 cm/s], the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

Duignan, M.R.; Greene, G.A. [Brookhaven National Lab., Upton, NY (United States); Irvine, T.F., Jr. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering

1992-04-01T23:59:59.000Z

458

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured (0 to 8.5 cm/s), the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

Duignan, M.R.; Greene, G.A. (Brookhaven National Lab., Upton, NY (United States)); Irvine, T.F., Jr. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering)

1992-04-01T23:59:59.000Z

459

Plasma wake field XUV radiation source  

DOE Patents [OSTI]

A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

Prono, Daniel S. (Los Alamos, NM); Jones, Michael E. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

460

IOP PUBLISHING JOURNAL OF PHYSICS A: MATHEMATICAL AND THEORETICAL J. Phys. A: Math. Theor. 40 (2007) 50255044 doi:10.1088/1751-8113/40/19/007  

E-Print Network [OSTI]

of paraxial waves in the radiative transfer limits. The scaling limits give rises to deterministic transport 5025 #12;5026 A C Fannjiang equation. In other words, in radiative transfer, the whole hierarchy of two-frequency moment equations is reduced to a single radiative-transfer-like equation. Let Lz and Lx be, respectively

Fannjiang, Albert

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

TECH TRANSFER TECHNOLOGY TRANSFER PROGRAM INSTITUTE OF TRANSPORTATION STUDIES UNIVERSITY OF CALIFORNIA, BERKELEY  

E-Print Network [OSTI]

TECH TRANSFER TECHNOLOGY TRANSFER PROGRAM · INSTITUTE OF TRANSPORTATION STUDIES · UNIVERSITY THURSDAY SATURDAYFRIDAYWEDNESDAYTUESDAY TECHNOLOGY TRANSFER PROGRAM · INSTITUTE OF TRANSPORTATION STUDIES's to another year of working safer and smarter. Laura Melendy Director, Technology Transfer Program #12;AUGUST

California at Berkeley, University of

462

Numerical integration of variational equations  

E-Print Network [OSTI]

We present and compare different numerical schemes for the integration of the variational equations of autonomous Hamiltonian systems whose kinetic energy is quadratic in the generalized momenta and whose potential is a function of the generalized positions. We apply these techniques to Hamiltonian systems of various degrees of freedom, and investigate their efficiency in accurately reproducing well-known properties of chaos indicators like the Lyapunov Characteristic Exponents (LCEs) and the Generalized Alignment Indices (GALIs). We find that the best numerical performance is exhibited by the \\textit{`tangent map (TM) method'}, a scheme based on symplectic integration techniques which proves to be optimal in speed and accuracy. According to this method, a symplectic integrator is used to approximate the solution of the Hamilton's equations of motion by the repeated action of a symplectic map $S$, while the corresponding tangent map $TS$, is used for the integration of the variational equations. A simple and systematic technique to construct $TS$ is also presented.

Ch. Skokos; E. Gerlach

2010-09-29T23:59:59.000Z

463

Radiation Shielding and Radiological Protection  

E-Print Network [OSTI]

Radiation Shielding and Radiological Protection J. Kenneth Shultis Richard E. Faw Department@triad.rr.com Radiation Fields and Sources ................................................ . Radiation Field Variables........................................................... .. Direction and Solid Angle Conventions ......................................... .. Radiation Fluence

Shultis, J. Kenneth

464

Radiative Exchange Between Square Parallel Channels in a Concentric Monolith Structure  

E-Print Network [OSTI]

Mean gas heat capacity (J mol \\Gamma1 K \\Gamma1 ) E Radiation view factor (multichannel model) F; d combustor for a gas turbine engine, where temperatures may be as high as 1550 K [3] and radiative exchange an important role. Initially, this paper derives the system of integral equations that is used to model radia

Bath, University of

465

Transport equations in tokamak plasmas  

SciTech Connect (OSTI)

Tokamak plasma transport equations are usually obtained by flux surface averaging the collisional Braginskii equations. However, tokamak plasmas are not in collisional regimes. Also, ad hoc terms are added for neoclassical effects on the parallel Ohm's law, fluctuation-induced transport, heating, current-drive and flow sources and sinks, small magnetic field nonaxisymmetries, magnetic field transients, etc. A set of self-consistent second order in gyroradius fluid-moment-based transport equations for nearly axisymmetric tokamak plasmas has been developed using a kinetic-based approach. The derivation uses neoclassical-based parallel viscous force closures, and includes all the effects noted above. Plasma processes on successive time scales and constraints they impose are considered sequentially: compressional Alfven waves (Grad-Shafranov equilibrium, ion radial force balance), sound waves (pressure constant along field lines, incompressible flows within a flux surface), and collisions (electrons, parallel Ohm's law; ions, damping of poloidal flow). Radial particle fluxes are driven by the many second order in gyroradius toroidal angular torques on a plasma species: seven ambipolar collision-based ones (classical, neoclassical, etc.) and eight nonambipolar ones (fluctuation-induced, polarization flows from toroidal rotation transients, etc.). The plasma toroidal rotation equation results from setting to zero the net radial current induced by the nonambipolar fluxes. The radial particle flux consists of the collision-based intrinsically ambipolar fluxes plus the nonambipolar fluxes evaluated at the ambipolarity-enforcing toroidal plasma rotation (radial electric field). The energy transport equations do not involve an ambipolar constraint and hence are more directly obtained. The 'mean field' effects of microturbulence on the parallel Ohm's law, poloidal ion flow, particle fluxes, and toroidal momentum and energy transport are all included self-consistently. The final comprehensive equations describe radial transport of plasma toroidal rotation, and poloidal and toroidal magnetic fluxes, as well as the usual particle and energy transport.

Callen, J. D.; Hegna, C. C.; Cole, A. J. [University of Wisconsin, Madison, Wisconsin 53706-1609 (United States)

2010-05-15T23:59:59.000Z

466

Chapter 2' First order Differential Equations I 2,] Linear Equations ...  

E-Print Network [OSTI]

Alternatively, you can use a numerical approximation method, such as those discussed in. Chapter 8 ... and produce graphs of solutions of differential equations. ..... hand, the effective escape velocity can be signi?cantly reduced if the body is transported a ... the cross section of the (smooth) out?ow stream is smaller than n.

467

Summary Report on Federal Laboratory Technology Transfer  

E-Print Network [OSTI]

Summary Report on Federal Laboratory Technology Transfer Agency Approaches; FY 2001 Activity Metrics and Outcomes 2002 Report to the President and the Congress under the Technology Transfer: FEDERAL LAB TECHNOLOGY TRANSFER TABLE OF CONTENTS LIST OF FIGURES AND TABLES

Perkins, Richard A.

468

Heat and Mass Transfer Modeling of Dry Gases in the Cathode of PEM Fuel Cells  

E-Print Network [OSTI]

Heat and Mass Transfer Modeling of Dry Gases in the Cathode of PEM Fuel Cells M.J. Kermani1 J and N2, through the cathode of a proton exchange membrane (PEM) fuel cell is studied numerically) an energy equation, written in a form that has enthalpy as the dependent variable. Keywords: PEM fuel cells

Stockie, John

469

TERSat: Trapped Energetic Radiation Satellite  

E-Print Network [OSTI]

Radiation damage caused by interactions with high-energy particles in the Van Allen Radiation Belts is a leading

Clements, Emily B.

2012-01-01T23:59:59.000Z

470

Exact Controllability of the Superlinear Heat Equation  

SciTech Connect (OSTI)

The exact internal and boundary controllability of parabolic equations with superlinear nonlinearity is studied.

Barbu, V. [Institute of Mathematics of Romanian Academy, Blvd. Carol, 6600 Iasi (Romania)], E-mail: barbu@uaic.ro

2000-07-01T23:59:59.000Z

471

Compatibility of equations with truncated Newton's binomials  

E-Print Network [OSTI]

The resolvability of equations in integers containing truncated Newton's binomial, is determined by the divisibility of the binomial by the characteristic parameters of the equation, which most often is the binomial exponent. Two types of equations containing binomials from two and three integers are investigated. Conditions of resolvability of the equations are specified based on the characteristics of their parameters.

Anatoly A. Grinberg

2014-06-19T23:59:59.000Z

472

FPEOS: A First-Principles Equation of State Table of Deuterium for Inertial Confinement Fusion Applications  

E-Print Network [OSTI]

FPEOS: A First-Principles Equation of State Table of Deuterium for Inertial Confinement Fusion) Understanding and designing inertial confinement fusion (ICF) implosions through radiation- hydrodynamics. To minimize the drive energy for ignition, the imploding shell of DT- fuel needs to be kept as cold

Militzer, Burkhard

473

Radiation Related Terms Basic Terms  

E-Print Network [OSTI]

Radiation Related Terms Basic Terms Radiation Radiation is energy in transit in the form of high not carry enough energy to separate molecules or remove electrons from atoms. Ionizing radiation Ionizing radiation is radiation with enough energy so that during an interaction with an atom, it can remove tightly

Vallino, Joseph J.

474

Radiation: Facts, Risks and Realities  

E-Print Network [OSTI]

of Radiation 3 Understanding Radiation Risks 6 Naturally Occurring (Background) Radiation 7 Man-Made Radiation, beta particles and gamma rays. Other types, such as x-rays, can occur naturally or be machine-produced. Scientists have also learned that radiation sources are naturally all around us. Radiation can come from

475

MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER  

E-Print Network [OSTI]

MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER "ENGINEERING APPLICATIONS OF FRACTAL and multiphase flow & heat transfer will be stressed. This paper will begin by reviewing some important concepts

Lahey, Richard T.

476

Transferring Data from Batch Jobs at NERSC  

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

Transferring Data from Batch Jobs Transferring Data from Batch Jobs Examples Once you are set up for automatic authentication (see HPSS Passwords) you can access HPSS within batch...

477

USDOE Technology Transfer, Working with DOE  

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

Deployment SBIRSTTR - Small Business Innovation Research and Small Business Technology Transfer Advanced Research Projects Agency-Energy (ARPA-E) Oil & Gas Technology Transfer...

478

Technology Transfer Overview | Department of Energy  

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

Technology Transfer Overview Technology Transfer Overview Through strategic investments in science and technology, the U.S. Department of Energy (DOE) helps power and secure...

479

Technology Transfer for Brownfields Redevelopment Project | Department...  

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

Technology Transfer for Brownfields Redevelopment Project Technology Transfer for Brownfields Redevelopment Project The U.S. Department of Energy has provided six computers to...

480

PAVEMENT TECHNOLOGY UPDATE This Technology Transfer Program  

E-Print Network [OSTI]

PAVEMENT TECHNOLOGY UPDATE This Technology Transfer Program publication is funded by the Division to them in California. TECHNOLOGY TRANSFER PROGRAM MAY 2011, VOL. 3, NO. 1 California's Transition

California at Berkeley, University of

Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Preparing for Transfer Biological Engineering  

E-Print Network [OSTI]

Environmental Engineering Game Design Industrial Systems & Information Technology Information Science MaterialsPreparing for Transfer Majors: Biological Engineering Chemical Engineering Civil Engineering Computer Science Electrical & Computer Engineering Engineering Physics Environmental Engineering

Walter, M.Todd

482

Electrohydrodynamically enhanced condensation heat transfer  

E-Print Network [OSTI]

In a condenser the thickness of the liquid condensate film covering the cooled surface constitutes a resistance to the heat transfer. By establishing a non uniform electric field in the vicinity of the condensation surface the extraction of liquid...

Wawzyniak, Markus

2012-06-07T23:59:59.000Z

483

Knowledge Capture and Transfer Program  

Broader source: Energy.gov [DOE]

The Office of Learning and Workforce Development is working with Heads of Departmental Elements, DOE senior leaders and subject-matter-experts to capture and transfer the knowledge and experiences...

484

Equation of State of Graphite-like BC,  

SciTech Connect (OSTI)

The compressibility of turbostratic boron-substituted graphite (t-BC) was measured up to 12 GPa at room temperature using energy-dispersive X-ray powder diffraction with synchrotron radiation. A fit to the experimental p-V data using Birch-Murnaghan equation of state gives values of the t-BC bulk modulus 23(2) GPa and its pressure derivative 8.0(6). These values point to a higher compressibility of t-BC as compared to turbostratic graphite.

Solozhenko,V.; Kurakevych, O.; Solozhenko, E.; Chen, J.; Parise, J.

2006-01-01T23:59:59.000Z

485

Spring 2014 Heat Transfer -2  

E-Print Network [OSTI]

Spring 2014 Heat Transfer - 2 A thin electronic chip is in the shape of a square wafer, b = 1 cm surface of the chip with a heat transfer coefficient of h = 100 W/m2 -K. Assume the chip has a uniform per side with a mass of m = 0.3 grams and specific heat of C = 103 J/kg-K. The chip is mounted

Virginia Tech

486

2. System boundaries; Balance equations  

E-Print Network [OSTI]

;5/28 Systems and boundaries /3 An isolated system is a special kind of closed system Pictures: KJ05 Q = heat W Example: an electric hot water heater in a house ­ The electric heater is a closed system ­ The water1/28 2. System boundaries; Balance equations Ron Zevenhoven ?bo Akademi University Thermal and flow

Zevenhoven, Ron

487

Radiation Reaction, Renormalization and Poincar Symmetry  

E-Print Network [OSTI]

We consider the self-action problem in classical electrodynamics of a massive point-like charge, as well as of a massless one. A consistent regularization procedure is proposed, which exploits the symmetry properties of the theory. The radiation reaction forces in both 4D and 6D are derived. It is demonstrated that the Poincar\\'e-invariant six-dimensional electrodynamics of the massive charge is renormalizable theory. Unlike the massive case, the rates of radiated energy-momentum tend to infinity whenever the source is accelerated. The external electromagnetic fields, which do not change the velocity of the particle, admit only its presence within the interaction area. The effective equation of motion is the equation for eigenvalues and eigenvectors of the electromagnetic tensor. The interference part of energy-momentum radiated by two massive point charges arbitrarily moving in flat spacetime is evaluated. It is shown that the sum of work done by Lorentz forces of charges acting on one another exhausts the effect of combination of outgoing electromagnetic waves generated by the charges.

Yurij Yaremko

2005-11-25T23:59:59.000Z

488

ANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANALYSIS & PDEANA  

E-Print Network [OSTI]

but it is essential for the stability estimate (9). The radiative transport equation is given by · x u(x, ) + (x, )u UHLMANN We study the direct and an inverse source problem for the radiative transfer equation arising of the domain. The radiations in OMI are governed by the equations of radiative transfer and the inverse problem

Stefanov, Plamen

489

Couette flow regimes with heat transfer in rarefied gas  

SciTech Connect (OSTI)

Based on numerical solution of the Boltzmann equation by direct statistic simulation, the Couette flow with heat transfer is studied in a broad range of ratios of plate temperatures and Mach numbers of a moving plate. Flow regime classification by the form of the dependences of the energy flux and friction stress on the Knudsen number Kn is proposed. These dependences can be simultaneously monotonic and nonmonotonic and have maxima. Situations are possible in which the dependence of the energy flux transferred to a plate on Kn has a minimum, while the dependence of the friction stress is monotonic or even has a maximum. Also, regimes exist in which the dependence of the energy flux on Kn has a maximum, while the dependence of the friction stress is monotonic, and vice versa.

Abramov, A. A., E-mail: alabr54@mail.ru; Butkovskii, A. V., E-mail: albutkov@mail.ru [Zhukovski Central Aerohydrodynamics Institute (Russian Federation)

2013-06-15T23:59:59.000Z

490

Effect of turbulent heat transfer on continuous ingot solidification  

SciTech Connect (OSTI)

For many continuous ingot casting processes, turbulent heat transfer in the molten pool plays a critical role which, along with buoyancy and surface tension, is responsible for the quality of the end products. Based on a modified low Reynolds number K-[epsilon] two-equation closure, accounting for the phase change and mushy zone formation, the effect of turbulent heat transfer on the solidification characteristics during titanium alloy ingot casting in an electron beam melting process is investigated. The overall heat transfer rate is enhanced by turbulent transport via two sources, one through the correlated velocity and temperature fluctuations present for both single- and multi-phase flows, and the other through the correlated velocity and release of latent heat fluctuations which are unique to the flows with phase change. The roles played by both mechanisms are identified and assessed. The present turbulence model predicts that although the mushy zone defined by the mean temperature field is generally of substantial thickness as a result of the convection effect, the actual instantaneous zone thickness varies substantially due to turbulence effect. This finding is in contrast to the traditionally held viewpoint, based on the conduction analysis, of a generally thin mushy zone. The impact of turbulent heat transfer on local dendrite formation and remelting is illustrated and the issues involved in model development highlighted.

Shyy, W.; Chen, M.H. (Univ. of Florida, Gainesville, FL (United States). Dept. of Aerospace Engineering); Pang, Y.; Wei, D.Y. (GE Aircraft Engines, Engineering Materials Technology Labs., Lynn, MA (United States)); Hunter, G.B. (GE Aircraft Engines, Engineering Materials Technology Labs., Cincinnati, OH (United States))

1993-01-01T23:59:59.000Z

491

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 16, No. 3, JulySeptember 2002  

E-Print Network [OSTI]

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Vol. 16, No. 3, July­September 2002 Three against the sizes of time increment and grid cell and angular discrete order are examined. The false order in SN approximation n = number of angular discretization Q = radiative heat ux R = re ectance r

Guo, Zhixiong "James"

492

E-Print Network 3.0 - anisotropic porous medium Sample Search...  

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

Mathematics Page: << < 1 2 3 4 5 > >> Page: << < 1 2 3 4 5 > >> 21 Generalized radiative transfer equation for porous medium upscaling: application to the radiative Fourier...

493

RHOBOT: Radiation hardened robotics  

SciTech Connect (OSTI)

A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

Bennett, P.C.; Posey, L.D. [Sandia National Labs., Albuquerque, NM (United States)

1997-10-01T23:59:59.000Z

494

Solar radiation intensity calculations  

E-Print Network [OSTI]

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...

Levine, Randolph Steven

1978-01-01T23:59:59.000Z

495

Surface Radiation from GOES: A Physical Approach; Preprint  

SciTech Connect (OSTI)

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.

Habte, A.; Sengupta, M.; Wilcox, S.

2012-09-01T23:59:59.000Z

496

Atomic Radiation (Illinois)  

Broader source: Energy.gov [DOE]

This article states permissible levels of radiation in unrestricted areas, environmental standards for uranium fuel cycle and information about notification of incidents.

497

Radiation Hazards Program (Minnesota)  

Broader source: Energy.gov [DOE]

These regulations, promulgated by the Department of Health, set allowable radiation standards and mitigation practices, as well as procedures for the transportation of hazardous material.

498

Deep Eutectic Salt Formulations Suitable as Advanced Heat Transfer Fluids  

SciTech Connect (OSTI)

Concentrating solar power (CSP) facilities are comprised of many miles of fluid-filled pipes arranged in large grids with reflective mirrors used to capture radiation from the sun. Solar radiation heats the fluid which is used to produce steam necessary to power large electricity generation turbines. Currently, organic, oil-based fluid in the pipes has a maximum temperature threshold of 400 C, allowing for the production of electricity at approximately 15 cents per kilowatt hour. The DOE hopes to foster the development of an advanced heat transfer fluid that can operate within higher temperature ranges. The new heat transfer fluid, when used with other advanced technologies, could significantly decrease solar electricity cost. Lower costs would make solar thermal electricity competitive with gas and coal and would offer a clean, renewable source of energy. Molten salts exhibit many desirable heat transfer qualities within the range of the project objectives. Halotechnics developed advanced heat transfer fluids (HTFs) for application in solar thermal power generation. This project focused on complex mixtures of inorganic salts that exhibited a high thermal stability, a low melting point, and other favorable characteristics. A high-throughput combinatorial research and development program was conducted in order to achieve the project objective. Over 19,000 candidate formulations were screened. The workflow developed to screen various chemical systems to discover salt formulations led to mixtures suitable for use as HTFs in both parabolic trough and heliostat CSP plants. Furthermore, salt mixtures which will not interfere with fertilizer based nitrates were discovered. In addition for use in CSP, the discovered salt mixtures can be applied to electricity storage, heat treatment of alloys and other industrial processes.

Raade, Justin; Roark, Thomas; Vaughn, John; Bradshaw, Robert

2013-07-22T23:59:59.000Z

499

The dynamical mass ejection from binary neutron star mergers: Radiation-hydrodynamics study in general relativity  

E-Print Network [OSTI]

We perform radiation-hydrodynamics simulations of binary neutron star mergers in numerical relativity on the Japanese "K" supercomputer, taking into account neutrino cooling and heating by an updated leakage-plus-transfer scheme for the first time. Neutron stars are modeled by three modern finite-temperature equations of state (EOS) developed by Hempel and his collaborators. We find that the electron fraction has a broad distribution due to the weak processes and shock heating. The properties of the ejecta such as total mass, average electron fraction, and thermal energy depend strongly on the EOS. Only for a soft EOS (the so-called SFHo), the ejecta mass exceeds $0.01M_{\\odot}$. In this case, the electron fraction has a broad distribution which is well-suited for the production of the solar-like $r$-process abundance. For the other stiff EOS (DD2 and TM1), for which a long-lived massive neutron star is formed after the merger, the ejecta mass is smaller than $0.01M_{\\odot}$, although broad electron-fraction ...

Sekiguchi, Yuichiro; Kyutoku, Koutarou; Shibata, Masaru

2015-01-01T23:59:59.000Z

500

Technology Transfer Office FY2011 Annual Report  

E-Print Network [OSTI]

Technology Transfer Office FY2011 Annual Report #12;TECHNOLOGY TRANSFER ADVISORY COMMITTEES The UC San Diego Technology Transfer Advisory Committee (TTAC) is responsible for general oversight of the university? s technology transfer program. This standing committee is appointed by the chancellor

Hasty, Jeff