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Note: This page contains sample records for the topic "radiative transfer equation" from the National Library of EnergyBeta (NLEBeta).
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1

The Scaling Group of the Radiative Transfer Equation  

Science Conference Proceedings (OSTI)

We show that the equation of radiative transfer is invariant under a group of simultaneous transformations of the scale (i.e., the optical thickness) and the phase function. In this way, we provide a unified explanation of various empirical ...

Bruce H. J. McKellar; Michael A. Box

1981-05-01T23:59:59.000Z

2

Choosing an Approximation to the Equation of Radiative Transfer  

Science Conference Proceedings (OSTI)

We examine the accuracy of the PL, approximation to the equation of radiative transfer in the presence of scattering/absorbing clouds of various optical thicknesses. We find that very accurate net fluxes can be obtained with the P1, (two-stream) ...

James A. Fillmore; Alan H. Karp

1980-08-01T23:59:59.000Z

3

Test plan for validation of the radiative transfer equation.  

SciTech Connect

As the capabilities of numerical simulations increase, decision makers are increasingly relying upon simulations rather than experiments to assess risks across a wide variety of accident scenarios including fires. There are still, however, many aspects of fires that are either not well understood or are difficult to treat from first principles due to the computational expense. For a simulation to be truly predictive and to provide decision makers with information which can be reliably used for risk assessment the remaining physical processes must be studied and suitable models developed for the effects of the physics. A set of experiments are outlined in this report which will provide soot volume fraction/temperature data and heat flux (intensity) data for the validation of models for the radiative transfer equation. In addition, a complete set of boundary condition measurements will be taken to allow full fire predictions for validation of the entire fire model. The experiments will be performed with a lightly-sooting liquid hydrocarbon fuel fire in the fully turbulent scale range (2 m diameter).

Ricks, Allen Joseph; Grasser, Thomas W.; Kearney, Sean Patrick; Jernigan, Dann A.; Blanchat, Thomas K.

2010-09-01T23:59:59.000Z

4

Explicit-implicit difference scheme for the joint solution of the radiative transfer and energy equations by the splitting method  

Science Conference Proceedings (OSTI)

High-order accurate explicit and implicit conservative predictor-corrector schemes are presented for the radiative transfer and energy equations in the multigroup kinetic approximation solved together by applying the splitting method with respect to ... Keywords: difference splitting schemes, radiative transfer equations

N. Ya. Moiseev

2013-03-01T23:59:59.000Z

5

Radiative transfer in plane-parallel media and Cauchy integral equations III. The finite case  

E-Print Network (OSTI)

We come back to the Cauchy integral equations occurring in radiative transfer problems posed in finite, plane-parallel media with light scattering taken as monochromatic and isotropic. Their solution is calculated following the classical scheme where a Cauchy integral equation is reduced to a couple of Fredholm integral equations. It is expressed in terms of two auxiliary functions $\\zeta_+$ and $\\zeta_-$ we introduce in this paper. These functions show remarkable analytical properties in the complex plane. They satisfy a simple algebraic relation which generalizes the factorization relation of semi-infinite media. They are regular in the domain of the Fredholm integral equations they satisfy, and thus can be computed accurately. As an illustration, the X- and Y-functions are calculated in the whole complex plane, together with the extension in this plane of the so-called Sobouti's functions.

B. Rutily; L. Chevallier; J. Bergeat

2006-01-16T23:59:59.000Z

6

Surface Albedo Estimates from Nimbus-7 ERB Data and a Two-Stream Approximation of the Radiative Transfer Equation  

Science Conference Proceedings (OSTI)

Solar zenith angle-dependent surface albedo is determined by equating top of the atmosphere (TOA) albedo evaluated from Nimbus-7 data with TOA albedo predicted by a two-layer, two-stream radiative transfer model of the atmosphere. Results are ...

Howard W. Barker; John A. Davies

1989-05-01T23:59:59.000Z

7

Radiative transfer in plane-parallel media and Cauchy integral equations II. The H-function  

E-Print Network (OSTI)

In the central part of this paper, we revisit the classical study of the H-function defined as the unique solution, regular in the right complex half-plane, of a Cauchy integral equation. We take advantage of our work on the N-function published in the first article of this series. The H-function is then used to solve a class of Cauchy integral equations occurring in transfer problems posed in plane-parallel media. We obtain a concise expression of the unique solution analytic in the right complex half-plane, then modified with the help of the residue theorem for numerical calculations.

B. Rutily; J. Bergeat; L. Chevallier

2006-01-16T23:59:59.000Z

8

N-Stream Approximations to Radiative Transfer  

Science Conference Proceedings (OSTI)

Schuster's two-stream approximation is first derived from Chandrasekhar's radiative transfer equation, and then generalized to an arbitrary number of streams. The resulting technique for solving the transfer equation that is similar to the ...

Charles Acquista; Frederick House; James Jafolla

1981-07-01T23:59:59.000Z

9

Multimode Radiative Transfer in Finite Optical Media. I: Fundamentals  

Science Conference Proceedings (OSTI)

In this paper we develop a new method for solving the transfer of radiation within a laterally finite optical medium. A new radiative transfer equation, based on a multimode approach, is developed which includes the explicit effects of the sides ...

Rudolph W. Preisendorfer; Graeme L. Stephens

1984-03-01T23:59:59.000Z

10

Stochastic Radiative Transfer in Partially Cloudy Atmosphere  

Science Conference Proceedings (OSTI)

A radiation treatment of the broken-cloud problem is presented, based upon various stochastic models of the equation of radiative transfer that consider the clouds and clear sky as a two-component mixture. These models, recently introduced in the ...

F. Malvagi; R. N. Byrne; G. C. Pomraning; R. C. J. Somerville

1993-07-01T23:59:59.000Z

11

Accounting for Unresolved Clouds in a 1D Infrared Radiative Transfer Model. Part I: Solution for Radiative Transfer, Including Cloud Scattering and Overlap  

Science Conference Proceedings (OSTI)

Various aspects of infrared radiative transfer through clouds are investigated. First, three solutions to the IR radiative transfer equation are presented and assessed, each corresponding to a different approximation for the Planck function. It ...

J. Li

2002-12-01T23:59:59.000Z

12

Semi-implicit time integration for PN thermal radiative transfer  

Science Conference Proceedings (OSTI)

Implicit time integration involving the solution of large systems of equations is the current paradigm for time-dependent radiative transfer. In this paper we present a semi-implicit, linear discontinuous Galerkin method for the spherical harmonics (P"N) ... Keywords: Asymptotic diffusion limit, Discontinuous Galerkin, PN approximation, Thermal radiative transfer

Ryan G. McClarren; Thomas M. Evans; Robert B. Lowrie; Jeffery D. Densmore

2008-08-01T23:59:59.000Z

13

Incorporating the Effects of 3D Radiative Transfer in the Presence of Clouds into Two-Stream Multilayer Radiation Schemes  

Science Conference Proceedings (OSTI)

This paper presents a new method for representing the important effects of horizontal radiation transport through cloud sides in two-stream radiation schemes. Ordinarily, the radiative transfer equations are discretized separately for the clear ...

Robin J. Hogan; Jonathan K. P. Shonk

2013-02-01T23:59:59.000Z

14

Two-Dimensional Radiative Transfer in Cloudy Atmospheres: The Spherical Harmonic Spatial Grid Method  

Science Conference Proceedings (OSTI)

A new two-dimensional monochromatic method that computes the transfer of solar or thermal radiation through atmospheres with arbitrary optical properties is described. The model discretizes the radiative transfer equation by expanding the angular ...

K. Franklin Evans

1993-09-01T23:59:59.000Z

15

Discrete diffusion Monte Carlo for frequency-dependent radiative transfer  

SciTech Connect

Discrete Diffusion Monte Carlo (DDMC) is a technique for increasing the efficiency of Implicit Monte Carlo radiative-transfer simulations. In this paper, we develop an extension of DDMC for frequency-dependent radiative transfer. We base our new DDMC method on a frequency-integrated diffusion equation for frequencies below a specified threshold. Above this threshold we employ standard Monte Carlo. With a frequency-dependent test problem, we confirm the increased efficiency of our new DDMC technique.

Densmore, Jeffrey D [Los Alamos National Laboratory; Kelly, Thompson G [Los Alamos National Laboratory; Urbatish, Todd J [Los Alamos National Laboratory

2010-11-17T23:59:59.000Z

16

Boundary conditions for NLTE polarized radiative transfer with incident radiation  

E-Print Network (OSTI)

Polarized NLTE radiative transfer in the presence of scattering in spectral lines and/or in continua may be cast in a so-called reduced form for six reduced components of the radiation field. In this formalism the six components of the reduced source function are angle-independent quantities. It thus reduces drastically the storage requirement of numerical codes. This approach encounters a fundamental problem when the medium is illuminated by a polarized incident radiation, because there is a priori no way of relating the known (and measurable) Stokes parameters of the incident radiation to boundary conditions for the reduced equations. The origin of this problem is that there is no unique way of deriving the radiation reduced components from its Stokes parameters (only the inverse operation is clearly defined). The method proposed here aims at enabling to work with arbitrary incident radiation field (polarized or unpolarized). In previous works an ad-hoc treatment of the boundary conditions, applying to case...

Faurobert, Marianne; Atanackovic, Olga

2013-01-01T23:59:59.000Z

17

A Rapid Radiative Transfer Model for Reflection of Solar Radiation  

Science Conference Proceedings (OSTI)

A rapid analytical radiative transfer model for reflection of solar radiation in plane-parallel atmospheres is developed based on the Sobolev approach and the delta function transformation technique. A distinct advantage of this model over ...

X. Xiang; E. A. Smith; C. G. Justus

1994-07-01T23:59:59.000Z

18

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

19

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

20

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

2010-05-06T23:59:59.000Z

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

Multiresolution Analysis of Radiative Transfer through Inhomogeneous Media. Part II: Validation and New Insights  

Science Conference Proceedings (OSTI)

The multiresolution radiative transfer equations of Part I of this paper are solved numerically for the case of inhomogeneous model clouds using Meyer’s basis functions. After analyzing the properties of Meyer’s connection coefficients and ...

Nicolas Ferlay; Harumi Isaka; Philip Gabriel; Albert Benassi

2006-04-01T23:59:59.000Z

22

A Fourier–Riccati Approach to Radiative Transfer. Part I: Foundations  

Science Conference Proceedings (OSTI)

The three-dimensional equation of radiative transfer is formally solved using a Fourier-Riccati approach while calculations are performed on cloudy media embedded in a two-dimensional space. An extension to Stephens’ work, this study addresses ...

P. M. Gabriel; S-C. Tsay; G. L. Stephens

1993-09-01T23:59:59.000Z

23

Radiative Transfer through Arbitrarily Shaped Optical Media. Part II. Group Theory and Simple Closures  

Science Conference Proceedings (OSTI)

This paper presents a formulation of the radiative transfer equation which allows for the distinction between various groups of spatial scales of variation that comprise the radiance field. Such a formulation provides a convenient means for ...

Graeme L. Stephens

1988-06-01T23:59:59.000Z

24

A New Look at the Discrete Ordinate Method for Radiative Transfer Calculations in Anisotropically Scattering Atmospheres  

Science Conference Proceedings (OSTI)

The difficulties inherent in the conventional numerical implementation of the discrete ordinate method (following Chandrasekhar's prescription) for solving the radiative transfer equation are discussed. A matrix formulation is developed to ...

Knut Stamnes; Roy A. Swanson

1981-02-01T23:59:59.000Z

25

An alternative Monte Carlo approach to the thermal radiative transfer problem  

SciTech Connect

The usual Monte Carlo approach to the thermal radiative transfer problem is to view Monte Carlo as a solution technique for the nonlinear thermal radiative transfer equations. The equations contain time derivatives which are approximated by introducing small time steps. An alternative approach avoids time steps by using Monte Carlo to directly sample the time at which the next event occurs. That is, the time is advanced on a natural event-by-event basis rather than by introducing an artificial time step.

Booth, Thomas E., E-mail: teb@lanl.go [Mail Stop A143, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2011-02-20T23:59:59.000Z

26

Parallel Jacobian-free Newton Krylov solution of the discrete ordinates method with flux limiters for 3D radiative transfer  

Science Conference Proceedings (OSTI)

The present study introduces a parallel Jacobian-free Newton Krylov (JFNK) general minimal residual (GMRES) solution for the discretized radiative transfer equation (RTE) in 3D, absorbing, emitting and scattering media. For the angular and spatial discretization ... Keywords: Collimated radiation, Discrete ordinates method (DOM) SN, Electromagnetic radiation, Flux limiters, General Minimal Residual (GMRES), Gram-Schmidt, Householder, Jacobian free Newton-Krylov (JFNK), Parallel MPI, Radiative transfer equation (RTE), TVD, Threads

William F. Godoy; Xu Liu

2012-06-01T23:59:59.000Z

27

Original article: Comparison of numerical models in radiative heat transfer with application to circuit-breaker simulations  

Science Conference Proceedings (OSTI)

Two different modeling approaches for the numerical computation of the radiation energy exchange in the context of the simulation of high-voltage circuit breakers are investigated. These are the basic Radiative Transfer Equation method and the P1 model ... Keywords: CFD modeling, Circuit breakers, Finite volume discretization, P1 model, Radiative heat transfer

Matthieu Melot; Jean-Yves TréPanier; Ricardo Camarero; Eddy Petro

2012-08-01T23:59:59.000Z

28

Application of the adjoint method in atmospheric radiative transfer calculations  

DOE Green Energy (OSTI)

The transfer of solar radiation through a standard mid-latitude summer atmosphere including different amounts of aerosols (from clear to hazy) has been computed. The discrete-ordinates (S/sub N/) method, which has been developed to a high degree of computational efficiency and accuracy primarily for nuclear radiation shielding applications, is employed in a forward as well as adjoint mode. In the adjoint mode the result of a transfer calculation is an importance function (adjoint intensity) which allows the calculation of transmitted fluxes, or other radiative responses, for any arbitrary source distribution. The theory of the adjoint method is outlined in detail and physical interpretations are developed for the adjoint intensity. If, for example, the downward directed solar flux at ground level, F/sub lambda/ (z = 0), is desired for N different solar zenith angles, a regular (forward) radiative transfer calculation must be repeated for each solar zenith angle. In contrast, only 1 adjoint transfer calculation gives F/sub lambda/ (z = 0) for all solar zenith angles in a hazy aerosol atmosphere, for 1 wavelength interval, in 2.3 seconds on a CDC-7600 computer. A total of 155 altitude zones were employed between 0 and 70 km, and the convergence criterion for the ratio of fluxes from successive iterations was set at 2 x 10/sup -3/. Our results demonstrate not only the applicability of the highly efficient modern S/sub N/ codes, but indicate also conceptual and computational advantages when the adjoint formulation of the radiative transfer equation is used.

Gerstl, S.A.W.

1979-01-01T23:59:59.000Z

29

Development of a 3D atmospheric radiative transfer model  

Science Conference Proceedings (OSTI)

The 3D atmospheric radiative transfer model is established based on MODTRAN4. Moreover, the methods of calculating the ratio of atmospheric transmission, path radiation and single scattering solar radiation are presented. This 3D model is running by ... Keywords: MODTRAN4, atmospheric radiative transfer model, infrared radiation

Zhifeng Lu; Ge Li; Gang Guo; Kedi Huang

2008-05-01T23:59:59.000Z

30

Four-Stream Isosector Approximation for Solar Radiative Transfer  

Science Conference Proceedings (OSTI)

For radiative transfer in a thin atmosphere, an analytical four-stream isosector approximation for solar radiative transfer is presented. This approximation method is based on the assumption of four spherical sectors of isotropic intensities. ...

J. Li; J. S. Dobbie

1998-02-01T23:59:59.000Z

31

An Iterative Radiative Transfer Code For Ocean-Atmosphere Systems  

Science Conference Proceedings (OSTI)

We describe the details of an iterative radiative transfer code for computing the intensity and degree of polarization of diffuse radiation in models of the ocean-atmosphere system. The present code neglects the upwelling radiation from below the ...

Ziauddin Ahmad; Robert S. Fraser

1982-03-01T23:59:59.000Z

32

Posters The Effects of Radiative Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Posters The Effects of Radiative Transfer on Low-Level Cyclogenesis M. J. Leach and S. Raman Department of Marine, Earth and Atmospheric Sciences North Carolina State University Raleigh, North Carolina Introduction Many investigators have documented the role that thermodynamic forcing due to radiative flux divergence plays in the enhancement or generation of circulation. Most of these studies involve large-scale systems (e.g., Slingo et al. 1988), small-scale systems such as thunderstorms (Chen and Cotton 1988), and squall lines (Chin, submitted). The generation of circulation on large scales results from the creation of divergence in the upper troposphere and the maintenance of low-level potentially unstable air, and the maintenance of baroclinicity throughout

33

Two-Stream Approximations to Radiative Transfer in Planetary Atmospheres: A Unified Description of Existing Methods and a New Improvement  

Science Conference Proceedings (OSTI)

Existing two-stream approximations to radiative transfer theory for particulate media are shown to be represented by identical forms of coupled differential equations if the intensity is replaced by integrals of the intensity over hemispheres. ...

W. E. Meador; W. R. Weaver

1980-03-01T23:59:59.000Z

34

Modeling radiative transfer in photobioreactors for algal growth  

Science Conference Proceedings (OSTI)

Simulations of radiative transfer within an air-lift photobioreactor (PBR) are demonstrated by coupling it to the fluid hydrodynamics and employing wavelength dependant properties for the participating media. The radiative properties of the algal media ... Keywords: CFD, Computer simulation, Photobioreactor, Radiation transfer

Zachary C. Wheaton; Gautham Krishnamoorthy

2012-09-01T23:59:59.000Z

35

Cross Validation of Satellite Radiation Transfer Models during...  

Open Energy Info (EERE)

Cross Validation of Satellite Radiation Transfer Models during SWERA Project in Brazil (Abstract):  This work describes the cross validation between two different...

36

Improvements to the SHDOM Radiative Transfer Modeling Package  

NLE Websites -- All DOE Office Websites (Extended Search)

to the SHDOM Radiative Transfer Modeling Package K. F. Evans University of Colorado Boulder, Colorado W. J. Wiscombe National Aeronautics and Space Administration...

37

Present and Future Computing Requirements Radiative Transfer...  

NLE Websites -- All DOE Office Websites (Extended Search)

radiative shock (e.g., ensman 1994) gas temperature radiation temperature Local Thermodynamic Equilibrium (LTE) non-equilibrium (NLTE) CaII microphysics 1GB atomic data...

38

The Radiative Transfer Of CH{sub 4}-N{sub 2} Plasma Arc  

Science Conference Proceedings (OSTI)

Any physical modelling of a circuit-breaker arc therefore requires an understanding of the radiated energy which is taken into account in the form of a net coefficient. The evaluation of the net emission coefficient is performed by the knowledge of the chemical plasma composition and the resolution of the radiative transfer equation. In this paper, the total radiation which escapes from a CH{sub 4}-N{sub 2} plasma is calculated in the temperature range between 5000 and 30000K on the assumption of a local thermodynamic equilibrium and we have studied the nitrogen effect in the hydrocarbon plasmas.

Benallal, R. [Theoretical physics Laboratory, Physics Department of University Aboubekr Belkaied Tlemcen 13000 (Algeria); Liani, B. [Science Faculty, Hassiba Benbouali University, Chlef 02000 (Algeria)

2008-09-23T23:59:59.000Z

39

Solar Radiative Transfer for Wind-Sheared Cumulus Cloud Fields  

Science Conference Proceedings (OSTI)

The Monte Carlo method of photon transport was used to simulate solar radiative transfer for cumulus-like cloud forms (and cloud fields) possessing structural characteristics similar to those induced by wind shear. Using regular infinite arrays ...

Howard W. Barker

1994-05-01T23:59:59.000Z

40

An Improved Microwave Radiative Transfer Model for Tropical Oceanic Precipitation  

Science Conference Proceedings (OSTI)

In preparation for the launch of TRMM, new algorithms must be created that take advantage of the combined data from radar and microwave radiometers that will be on board the satellite. A microwave radiative transfer algorithm with a one-...

Jeffrey R. Tesmer; Thomas T. Wilheit

1998-05-01T23:59:59.000Z

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.


41

Multiple Scattering Parameterization in Thermal Infrared Radiative Transfer  

Science Conference Proceedings (OSTI)

A systematic formulation of various radiative transfer parameterizations is presented, including the absorption approximation (AA), ?-two-stream approximation (D2S), ?-four-stream approximation (D4S), and ?-two- and four-stream combination ...

Qiang Fu; K. N. Liou; M. C. Cribb; T. P. Charlock; A. Grossman

1997-12-01T23:59:59.000Z

42

Radiative Transfer in Cloud Fields with Random Geometry  

Science Conference Proceedings (OSTI)

Numerical results are given to estimate the importance of effects associated with the stochastic geometry of cloud fields. These results show the important of treating radiative transfer in broken clouds as a statistical problem. In the case of ...

Vladimir E. Zuev; Georgii A. Titov

1995-01-01T23:59:59.000Z

43

Community Radiative Transfer Model for Stratospheric Sounding Unit  

Science Conference Proceedings (OSTI)

To better use the Stratospheric Sounding Unit (SSU) data for reanalysis and climate studies, issues associated with the fast radiative transfer (RT) model for SSU have recently been revisited and the results have been implemented into the ...

Yong Chen; Yong Han; Quanhua Liu; Paul Van Delst; Fuzhong Weng

2011-06-01T23:59:59.000Z

44

Effective Diameter in Radiation Transfer: General Definition, Applications, and Limitations  

Science Conference Proceedings (OSTI)

Although the use of an effective radius for radiation transfer calculations in water clouds has been common for many years, the export of this concept to ice clouds has been fraught with uncertainty, due to the nonspherical shapes of ice ...

David L. Mitchell

2002-08-01T23:59:59.000Z

45

COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS  

Science Conference Proceedings (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

46

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. Guérout; J. Lussange; F. S. S. Rosa; J. -P. Hugonin; D. A. R. Dalvit; J. -J. Greffet; A. Lambrecht; S. Reynaud

2012-03-07T23:59:59.000Z

47

Spectrally Invariant Approximation within Atmospheric Radiative Transfer  

Science Conference Proceedings (OSTI)

Certain algebraic combinations of single scattering albedo and solar radiation reflected from, or transmitted through, vegetation canopies do not vary with wavelength. These “spectrally invariant relationships” are the consequence of wavelength ...

A. Marshak; Y. Knyazikhin; J. C. Chiu; W. J. Wiscombe

2011-12-01T23:59:59.000Z

48

Surface Solar Radiation Flux and Cloud Radiative Forcing for the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP): A Satellite, Surface Observations, and Radiative Transfer Model Study  

Science Conference Proceedings (OSTI)

This study presents surface solar radiation flux and cloud radiative forcing results obtained by using a combination of satellite and surface observations interpreted by means of a simple plane-parallel radiative transfer model called 2001. This ...

Catherine Gautier; Martin Landsfeld

1997-05-01T23:59:59.000Z

49

Cross Validation of Satellite Radiation Transfer Models during SWERA  

Open Energy Info (EERE)

Cross Validation of Satellite Radiation Transfer Models during SWERA Cross Validation of Satellite Radiation Transfer Models during SWERA Project in Brazil Dataset Summary Description (Abstract): This work describes the cross validation between two different core radiation transfer models that will be applied during the SWERA (Solar and Wind Energy Assessment): the BRAZIL-SR, and the SUNY-Albany. The model cross validation was performed by using two reference sites in Brazil: at Caicó (06°28'01"S - 037°05'05"W,175.8 m), and Florianópolis (27°34'18"S - 048°31'42"W, 10 m), Satellite data were collected by INPE-CPTEC for GOES-8, that also provides for its quality assessment, sectoring, storing and distribution to the participating teams. In this work we show the first results of this cross-validation along with some discussions on model deviations

50

Heat Transfer Analysis and Modeling of a Parabolic Trough Solar Receiver Implemented in Engineering Equation Solver  

DOE Green Energy (OSTI)

This report describes the development, validation, and use of a heat transfer model implemented in Engineering Equation Solver. The model determines the performance of a parabolic trough solar collector's linear receiver, also called a heat collector element. All heat transfer and thermodynamic equations, optical properties, and parameters used in the model are discussed. The modeling assumptions and limitations are also discussed, along with recommendations for model improvement.

Forristall, R.

2003-10-01T23:59:59.000Z

51

Handbook of radiative heat transfer in high-temperature gases  

Science Conference Proceedings (OSTI)

This work offers both an original method for calculating optical properties of low-temperature plasma at elevated densities ... and an effective new means for calculating radiative heat transfer in hot gases and plasma with arbitrary temperature and pressure distributions. These methods allow for automatic accounting of all details of the plasma spectrum, including the line structure. This volume contains radiant transfer in problems of heat transfer; integration over frequency; methods of partial characteristics; method of effective populations; calculation of partial characteristics; appendix: tabular data.

Soloukhin, R.I.; Golovnev, I.F.; Zamurayev, V.P.; Katsnelson, S.S.; Kovalskaya, G.A.; Sevastyanenko, V.G.; Soloukhin, R.I.

1987-01-01T23:59:59.000Z

52

A mesoscopic description of radiative heat transfer at the nanoscale  

E-Print Network (OSTI)

We present a formulation of the nanoscale radiative heat transfer (RHT) using concepts of mesoscopic physics. We introduce the analog of the Sharvin conductance using the quantum of thermal conductance. The formalism provides a convenient framework to analyse the physics of RHT at the nanoscale. Finally, we propose a RHT experiment in the regime of quantized conductance.

Svend-Age Biehs; Emmanuel Rousseau; Jean-Jacques Greffet

2011-03-11T23:59:59.000Z

53

CHAPARRAL: A library for solving large enclosure radiation heat transfer problems  

SciTech Connect

Large, three-dimensional enclosure radiation beat transfer problems place a heavy demand on computing resources such as computational cycles, memory requirements, disk I/O, and disk space usage. This is primarily due to the computational and memory requirements associated with the view factor calculation and subsequent access of the view factor matrix during solution of the radiosity matrix equation. This is a fundamental problem that constrains Sandia`s current modeling capabilities. Reducing the computational and memory requirements for calculating and manipulating view factors would enable an analyst to increase the level of detail at which a body could be modeled and would have a major impact on many programs at Sandia such as weapon and transportation safety programs, component survivability programs, energy programs, and material processing programs. CHAPARRAL is a library package written to address these problems and is specifically tailored towards the efficient solution of extremely large three-dimensional enclosure radiation heat transfer problems.

Glass, M.W.

1995-08-01T23:59:59.000Z

54

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

Science Conference Proceedings (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

55

Advances in Radiative Transfer Modeling in Support of Satellite Data Assimilation  

Science Conference Proceedings (OSTI)

Development of fast and accurate radiative transfer models for clear atmospheric conditions has enabled direct assimilation of clear-sky radiances from satellites in numerical weather prediction models. In this article, fast radiative transfer ...

Fuzhong Weng

2007-11-01T23:59:59.000Z

56

Scalable photon monte carlo algorithms and software for the solution of radiative heat transfer problems  

Science Conference Proceedings (OSTI)

Radiative heat transfer plays a central role in many combustion and engineering applications. Because of its highly nonlinear and nonlocal nature, the computational cost can be extremely high to model radiative heat transfer effects accurately. In this ...

Ivana Veljkovic; Paul E. Plassmann

2005-09-01T23:59:59.000Z

57

CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT  

Open Energy Info (EERE)

ISES- 2003 ISES- 2003 CROSS VALIDATION OF SATELLITE RADIATION TRANSFER MODELS DURING SWERA PROJECT IN BRAZIL Enio B. Pereira, Fernando R. Martins 1 Brazilian Institute for Space Research - INPE, São José dos Campos, 12245-970, SP, Brazil Phone + 55 12 39456741, Fax + 55 12 39456810, enio@dge.inpe.br Samuel L. Abreu, Hans Georg Beyer, Sergio Colle, and Solar Energy Laboratory - LABSOLAR - Department of Mechanical Engineering, Federal University of Santa Catarina -UFSC, Florianopolis, 88040-900, (SC), Brazil, Richard Perez The University at Albany (SUNY), ASRC-CESTM, Albany, 12203 (NY), USA Abstract - This work describes the cross validation between two different core radiation transfer models that will be applied during the SWERA (Solar and Wind Energy Assessment): the BRAZIL-SR, and the

58

Documentation for the intergalactic radiative transfer code IGMtransfer  

E-Print Network (OSTI)

This document describes the publically available numerical code "IGMtransfer", capable of performing intergalactic radiative transfer (RT) of light in the vicinity of the Lyman alpha (Lya) line. Calculating the RT in a (possibly adaptively refined) grid of cells resulting from a cosmological simulation, the code returns 1) a "transmission function", showing how the intergalactic medium (IGM) affects the Lya line at a given redshift, and 2) the "average transmission" of the IGM, making it useful for studying the results of reionization simulations.

Laursen, Peter

2010-01-01T23:59:59.000Z

59

Radiative Transfer Modeling of a Coniferous Canopy Characterized by Airborne Remote Sensing  

Science Conference Proceedings (OSTI)

Solar radiation beneath a forest canopy can have large spatial variations, but this is frequently neglected in radiative transfer models for large-scale applications. To explicitly model spatial variations in subcanopy radiation, maps of canopy ...

Richard Essery; Peter Bunting; Aled Rowlands; Nick Rutter; Janet Hardy; Rae Melloh; Tim Link; Danny Marks; John Pomeroy

2008-04-01T23:59:59.000Z

60

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. Fernández

2009-11-01T23:59:59.000Z

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.


61

Influence of Infrared Radiation on Attic Heat Transfer  

E-Print Network (OSTI)

An experimental study concerned with different modes of heal transfer in fibrous and cellulose insulating material is presented. A series of experiments were conducted using an attic simulator to determine the effects of ventilation on attic heat transfer, and the effect of infrared radiation on the thermal conductivity of the insulation system and on attic heat transfer. All the tests were performed at steady state conditions by controlling the roof deck temperature. Calculations are performed for insulation thicknesses between 1 inch (2.54cm) and 6.0 inches (15.24cm) and roof deck temperatures between 145°F (62.78°C) and 100°F (36.78°C). The temperature profiles within the insulation were measured by placing thermocouples at various levels within the insulation. The profiles for the cellulose insulation are linear. The profiles within the glass fiber insulation are non-linear due to the effect of infrared radiation. Also heat fluxes were measured through different insulation thicknesses and for different 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 was in good agreement with experimental results.

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

1985-01-01T23:59:59.000Z

62

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.

63

Post-Newtonian gravitational radiation and equations of motion via direct integration of the relaxed Einstein equations. III. Radiation reaction for binary systems with spinning bodies  

E-Print Network (OSTI)

Using post-Newtonian equations of motion for fluid bodies that include radiation-reaction terms at 2.5 and 3.5 post-Newtonian (PN) order (O[(v/c)^5] and O[(v/c)^7] beyond Newtonian order), we derive the equations of motion for binary systems with spinning bodies. In particular we determine the effects of radiation-reaction coupled to spin-orbit effects on the two-body equations of motion, and on the evolution of the spins. For a suitable definition of spin, we reproduce the standard equations of motion and spin-precession at the first post-Newtonian order. At 3.5PN order, we determine the spin-orbit induced reaction effects on the orbital motion, but we find that radiation damping has no effect on either the magnitude or the direction of the spins. Using the equations of motion, we find that the loss of total energy and total angular momentum induced by spin-orbit effects precisely balances the radiative flux of those quantities calculated by Kidder et al. The equations of motion may be useful for evolving inspiraling orbits of compact spinning binaries.

Clifford M. Will

2005-02-09T23:59:59.000Z

64

A Radiation Fog Model with a Detailed Treatment of the Interaction between Radiative Transfer and Fog Microphysics  

Science Conference Proceedings (OSTI)

A one-dimensional radiation fog model is presented which includes a detailed description of the interaction between atmospheric radiative transfer and the microphysical structure of the fog. Aerosol particles and activated cloud droplets are ...

A. Bott; U. Sievers; W. Zdunkowski

1990-09-01T23:59:59.000Z

65

Near-field radiative heat transfer for structured surfaces  

E-Print Network (OSTI)

We apply an analytical approach for determining the near-field radiative heat transfer between a metallic nanosphere and a planar semi-infinite medium with some given surface structure. This approach is based on a perturbative expansion, and evaluated to first order in the surface profile. With the help of numerical results obtained for some simple model geometries we discuss typical signatures that should be obtainable with a near-field scanning thermal microscope operated in either constant-height or constant-distance mode.

Svend-Age Biehs; Oliver Huth; Felix Rüting

2011-03-15T23:59:59.000Z

66

The "Z" Pulsed Radiation Source: Recent Developments in Equation of State Measurement Capabilities  

SciTech Connect

The Sandia Z machine is a source of intense radiation which can be used to drive ablative shocks for equation of state studies. In developing the capability to diagnose these types of studies on Z, techniques commonly used in conventional impact generated experiments were leveraged. The primary diagnostic transferred was velocity interferome~, VLSAR, [1] which not only provides Hugoniot particle velocity measurements, but also indications of shock stability and wave attenuation. In addition to a VISAR capability on the Z machine, methods for measuring shock velocity have been developed. When these measured parameters are used in conjunction with the Rankine-Hugoniot jump conditions, [2] material response at high temperatures and pressures can be inferred. With sample sizes used on Z being much smaller than those fielded in typical impact experiments, temporal resolution and methods of interfacing the diagnostics with the targets had to be improved. In this paper, a "standard" equation of state experiment, associated diagnostics, and some recent results in aluminum and beryllium will be discussed.

Asay, J.R.; Chandler, G.; Clark, B.; Fleming, K.; Hall, C.A.; Holland, K.; Trott, W.M.

1998-10-13T23:59:59.000Z

67

A 3-D multiband closure for radiation and neutron transfer moment models  

Science Conference Proceedings (OSTI)

We derive a 3D multi-band moment model and its associated closure for radiation and neutron transfer. The new closure is analytical and nonlinear but very simple. Its derivation is based on the maximum entropy closure and assumes a Wien shape for the ... Keywords: Maximum entropy closure, Moment models, Multi-band models, Multi-bin models, Neutron transfer, ODF, Radiative transfer

J. -F. Ripoll; A. A. Wray

2008-02-01T23:59:59.000Z

68

Cloudy Sky RRTM Shortwave Radiative Transfer and Comparison to the Revised ECMWF Shortwave Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloudy Sky RRTM Shortwave Radiative Transfer and Cloudy Sky RRTM Shortwave Radiative Transfer and Comparison to the Revised ECMWF Shortwave Model M. J. Iacono, J. S. Delamere, E. J. Mlawer, and S. A. Clough Atmospheric and Environmental Research, Inc. Lexington, Massachusetts J.-J. Morcrette European Centre for Medium-Range Weather Forecasts Reading, United Kingdom Introduction An important step toward improving radiative transfer codes in general circulation models (GCMs) is their thorough evaluation by comparison to measurements directly, or to other data-validated radiation models. This work extends the clear-sky shortwave (SW) GCM evaluation presented by Iacono et al. (2001) to computations including clouds. The rapid radiative transfer model (RRTM) SW radiation model accurately reproduces clear-sky direct beam fluxes from the Line-By-Line Radiative Transfer

69

Post-Newtonian gravitational radiation and equations of motion via direct integration of the relaxed Einstein equations. IV. Radiation reaction for binary systems with spin-spin coupling  

E-Print Network (OSTI)

Using post-Newtonian equations of motion for fluid bodies that include radiation-reaction terms at 2.5 and 3.5 post-Newtonian (PN) order O[(v/c)^5] and O[(v/c)^7] beyond Newtonian order), we derive the equations of motion for binary systems with spinning bodies, including spin-spin effects. In particular we determine the effects of radiation-reaction coupled to spin-spin effects on the two-body equations of motion, and on the evolution of the spins. We find that radiation damping causes a 3.5PN order, spin-spin induced precession of the individual spins. This contrasts with the case of spin-orbit coupling, where there is no effect on the spins at 3.5PN order. Employing the equations of motion and of spin precession, we verify that the loss of total energy and total angular momentum induced by spin-spin effects precisely balances the radiative flux of those quantities calculated by Kidder et al.

Han Wang; Clifford M. Will

2007-01-08T23:59:59.000Z

70

Implied Dynamic Feedback of 3D IR Radiative Transfer on Simulated...  

NLE Websites -- All DOE Office Websites (Extended Search)

of 3D IR Radiative Transfer on Simulated Cloud Fields D. B. Mechem and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies University of Oklahoma Norman,...

71

Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model  

Science Conference Proceedings (OSTI)

A thin cirrus cloud thermal infrared radiative transfer model has been developed for application to cloudy satellite data assimilation. This radiation model was constructed by combining the Optical Path Transmittance (OPTRAN) model, developed for ...

Qing Yue; K. N. Liou; S. C. Ou; B. H. Kahn; P. Yang; G. G. Mace

2007-11-01T23:59:59.000Z

72

Radiative Transfer in Cirrus Clouds. Part IV: On Cloud Geometry, Inhomogeneity, and Absorption  

Science Conference Proceedings (OSTI)

The effects of cloud geometry and inhomogeneity on the radiative properties of cirrus clouds are investigated by using the successive orders of scattering (SOS) approach for radiative transfer. This approach is an integral solution method that em ...

K. N. Liou; N. Rao

1996-11-01T23:59:59.000Z

73

Radiative Transfer through Arbitrarily Shaped Optical Media. Part I: A General Method of Solution  

Science Conference Proceedings (OSTI)

A general transform method is presented for studying problems of radiative transfer through absorbing, emitting and anisotropically scattering media exposed to arbitrary radiation conditions on its boundaries. The method permits quite arbitrary ...

Graeme L. Stephens

1988-06-01T23:59:59.000Z

74

Radiative Heat Transfer Analysis within Three-Dimensional Clouds Subjected to Solar and Sky Irradiation  

Science Conference Proceedings (OSTI)

A three-dimensional radiative heat transfer analysis of an arbitrary-shaped modeled cloud subjected to solar and sky irradiation has been performed. The Radiation Element Method by Ray Emission Model (REM2) was used for numerical simulation. ...

Toru Nishikawa; Shigenao Maruyama; Seigo Sakai

2004-12-01T23:59:59.000Z

75

A Coupled Atmosphere–Ocean Radiative Transfer System Using the Analytic Four-Stream Approximation  

Science Conference Proceedings (OSTI)

A coupled atmosphere–ocean radiative transfer model based on the analytic four-stream approximation has been developed. It is shown that this radiation model is computationally efficient and at the same time can achieve acceptable accuracy for ...

Wei-Liang Lee; K. N. Liou

2007-10-01T23:59:59.000Z

76

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

SciTech Connect

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

77

Two-fluid matter-quintessence FLRW models: energy transfer and the equation of state of the universe  

E-Print Network (OSTI)

Recent observations support the view that the universe is described by a FLRW model with $\\Omega_m^0 \\approx 0.3$, $\\Omega_{\\Lambda}^0 \\approx 0.7$, and $w \\leq -1/3$ at the present epoch. There are several theoretical suggestions for the cosmological $\\Lambda$ component and for the particular form of the energy transfer between this dark energy and matter. This gives a strong motive for a systematic study of general properties of two-fluid FLRW models. We consider a combination of one perfect fluid, which is quintessence with negative pressure ($p_Q = w\\epsilon_Q$), and another perfect fluid, which is a mixture of radiation and/or matter components with positive pressure ($p = \\beta \\epsilon_m$), which define the associated one-fluid model ($p = \\gamma \\epsilon$). We introduce a useful classification which contains 4 classes of models defined by the presence or absence of energy transfer and by the stationarity ($w = const.$ and $\\beta = const.$) or/and non stationarity ($w$ or $\\beta$ time dependent) of the equations of state. It is shown that, for given $w$ and $\\beta$, the energy transfer defines $\\gamma$ and, therefore, the total gravitating mass and dynamics of the model. We study important examples of two-fluid FLRW models within the new classification. The behaviour of the energy content, gravitating mass, pressure, and the energy transfer are given as functions of the scale factor. We point out three characteristic scales, $a_E$, $a_{\\cal P}$ and $a_{\\cal M}$, which separate periods of time in which quintessence energy, pressure and gravitating mass dominate. Each sequence of the scales defines one of 6 evolution types.

A. Gromov; Yu. Baryshev; P. Teerikorpi

2002-09-23T23:59:59.000Z

78

Polarized radiance fields under a dynamic ocean surface: a three-dimensional radiative transfer solution  

Science Conference Proceedings (OSTI)

The hybrid matrix operator, Monte Carlo (HMOMC) method previously reported [Appl. Opt.47, 1063-1071 (2008)APOPAI0003-693510.1364/AO.47.001063] is improved by neglecting higher-order terms in the coupling of the matrix operators and by introducing a dual grid scheme. The computational efficiency for solving the vector radiative transfer equation in a full 3D coupled atmosphere-surface-ocean system is substantially improved, and, thus, large-scale simulations of the radiance distribution become feasible. The improved method is applied to the computation of the polarized radiance field under realistic surface waves simulated by the power spectral density method. To the authors' best knowledge, this is the first time that the polarized radiance field under a dynamic ocean surface and the underwater image of an object above such an ocean surface have been reported.

You Yu; Zhai Pengwang; Kattawar, George W.; Yang Ping

2009-06-01T23:59:59.000Z

79

Modeling the Heating of Biological Tissue based on the Hyperbolic Heat Transfer Equation  

E-Print Network (OSTI)

In modern surgery, a multitude of minimally intrusive operational techniques are used which are based on the punctual heating of target zones of human tissue via laser or radio-frequency currents. Traditionally, these processes are modeled by the bioheat equation introduced by Pennes, who considers Fourier's theory of heat conduction. We present an alternative and more realistic model established by the hyperbolic equation of heat transfer. To demonstrate some features and advantages of our proposed method, we apply the obtained results to different types of tissue heating with high energy fluxes, in particular radiofrequency heating and pulsed laser treatment of the cornea to correct refractive errors. Hopefully, the results of our approach help to refine surgical interventions in this novel field of medical treatment.

Tung, M M; Molina, J A Lopez; Rivera, M J; Berjano, E J

2008-01-01T23:59:59.000Z

80

Analytical Delta-Four-Stream Doubling–Adding Method for Radiative Transfer Parameterizations  

Science Conference Proceedings (OSTI)

Although single-layer solutions have been obtained for the ?-four-stream discrete ordinates method (DOM) in radiative transfer, a four-stream doubling–adding method (4DA) is lacking, which enables us to calculate the radiative transfer through a ...

Feng Zhang; Zhongping Shen; Jiangnan Li; Xiuji Zhou; Leiming Ma

2013-03-01T23:59:59.000Z

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.


81

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network (OSTI)

W/m 2 .µm) f (?T ) Blackbody radiation function I ? SpectralW/m 2 .sr.µm) I b,? Blackbody radiation intensity (W/m 2 .can be treated as blackbody radiation at temperature T sur .

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

82

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

Science Conference Proceedings (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

83

A Three-Dimensional Radiative Transfer Model to Investigate the Solar Radiation within a Cloudy Atmosphere. Part I: Spatial Effects  

Science Conference Proceedings (OSTI)

A new Monte Carlo–based three-dimensional (3D) radiative transfer model of high spectral and spatial resolution is presented. It is used to investigate the difference in broadband solar radiation absorption, top-of-the-atmosphere upwelling, and ...

William O’Hirok; Catherine Gautier

1998-06-01T23:59:59.000Z

84

A Three-Dimensional Radiative Transfer Model to Investigate the Solar Radiation within a Cloudy Atmosphere. Part II: Spectral Effects  

Science Conference Proceedings (OSTI)

In this second part of a two-part paper, the spectral response of the interaction between gases, cloud droplets, and solar radiation is investigated using a Monte Carlo-based three-dimensional (3D) radiative transfer model with a spectral ...

William O’Hirok; Catherine Gautier

1998-10-01T23:59:59.000Z

85

An Update on Radiative Transfer Model Development at Atmospheric and Environmental Research, Inc.  

NLE Websites -- All DOE Office Websites (Extended Search)

Update on Radiative Transfer Model Development at Update on Radiative Transfer Model Development at Atmospheric and Environmental Research, Inc. J. S. Delamere, S. A. Clough, E. J. Mlawer, Sid-Ahmed Boukabara, K. Cady-Pereira, and M. Shepard Atmospheric and Environmental Research, Inc. Lexington, Maine Introduction Over the last decade, a suite of radiative transfer models has been developed at Atmospheric and Environmental Research, Inc. (AER) with support from the Atmospheric and Radiation Measurement (ARM) Program. These models span the full spectral regime from the microwave to the ultraviolet, and range from monochromatic to band calculations. Each model combines the latest spectroscopic advancements with radiative transfer algorithms to efficiently compute radiances, fluxes, and cooling

86

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

87

Full-Spectrum Correlated-k Distribution for Shortwave Atmospheric Radiative Transfer  

Science Conference Proceedings (OSTI)

The full-spectrum correlated k-distribution (FSCK) method, originally developed for applications in combustion systems, is adapted for use in shortwave atmospheric radiative transfer. By weighting k distributions by the solar source function, the ...

Daniel T. Pawlak; Eugene E. Clothiaux; Michael F. Modest; Jason N. S. Cole

2004-11-01T23:59:59.000Z

88

A Revised Cloud Overlap Scheme for Fast Microwave Radiative Transfer in Rain and Cloud  

Science Conference Proceedings (OSTI)

The assimilation of cloud- and precipitation-affected observations into weather forecasting systems requires very fast calculations of radiative transfer in the presence of multiple scattering. At the European Centre for Medium-Range Weather ...

Alan J. Geer; Peter Bauer; Christopher W. O’Dell

2009-11-01T23:59:59.000Z

89

Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections  

NLE Websites -- All DOE Office Websites (Extended Search)

Estimating Three-Dimensional Cloudy Radiative Transfer Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections C. Hannay and R. Pincus National Oceanic and Atmospheric Administration Climate Diagnostics Center Boulder, Colorado K. F. Evans Program in Atmospheric and Oceanic Sciences University of Colorado Boulder, Colorado Introduction Clouds in the atmosphere are finite in extent and variable in every direction and in time. Long data sets from ground-based profilers, such as lidars or cloud radars, could provide a very valuable set of observations to characterize this variability. We may ask how well such profiling instruments can represent the cloud structure as measured by the magnitude of the three-dimensional (3D) radiative transfer effect. The 3D radiative transfer effect is the difference between the domain average broadband solar surface

90

On the Correlated k-Distribution Method for Radiative Transfer in Nonhomogeneous Atmospheres  

Science Conference Proceedings (OSTI)

The correlated k-distribution method for radiative transfer in nonhomogeneous atmospheres is discussed in terms of the physical and mathematical conditions under which this method is valid. Two correlated conditions are necessary and sufficient ...

Qiang Fu; K. N. Liou

1992-11-01T23:59:59.000Z

91

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

92

A 3-D Canopy Radiative Transfer Model for Global Climate Modeling: Description, Validation and Application  

Science Conference Proceedings (OSTI)

The process of solar radiative transfer at the land surface is important to energy, water and carbon balance, especially for vegetated areas. Currently the most commonly used two-stream model considers the Plant Functional Types (PFTs) within a ...

Hua Yuan; Robert E. Dickinson; Yongjiu Dai; Muhammad J. Shaikh; Liming Zhou; Wei Shangguan; Duoying Ji

93

Entrainment-Mixing and Radiative Transfer Simulation in Boundary Layer Clouds  

Science Conference Proceedings (OSTI)

In general circulation models, clouds are parameterized and radiative transfer calculations are performed using the plane-parallel approximation over the cloudy fraction of each model grid. The albedo bias resulting from the plane-parallel ...

Frédérick Chosson; Jean-Louis Brenguier; Lothar Schüller

2007-07-01T23:59:59.000Z

94

Fluctuating-surface-current formulation of radiative heat transfer for arbitrary geometries  

E-Print Network (OSTI)

We describe a fluctuating-surface-current formulation of radiative heat transfer, applicable to arbitrary geometries in both the near and far field, that directly exploits efficient and sophisticated techniques from the ...

Rodriguez, Alejandro W.

95

Trace formulas for nonequilibrium 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 nonequilibrium. The results can be expressed ...

Bimonte, Giuseppe

96

Simple Radiative Transfer Methods for Calculating Domain-Averaged Solar Fluxes in Inhomogeneous Clouds  

Science Conference Proceedings (OSTI)

The use of cloud fraction as a means of incorporating horizontal cloud inhomogeneity in radiative transfer calculations is widespread in the atmospheric science community. This study addresses some issues pertaining to the use of cloud fraction ...

P. M. Gabriel; K. F. Evans

1996-03-01T23:59:59.000Z

97

The Successive-Order-of-Interaction Radiative Transfer Model. Part II: Model Performance and Applications  

Science Conference Proceedings (OSTI)

Radiative transfer models for scattering atmospheres that are accurate yet computationally efficient are required for many applications, such as data assimilation in numerical weather prediction. The successive-order-of-interaction (SOI) model is ...

Christopher W. O’Dell; Andrew K. Heidinger; Thomas Greenwald; Peter Bauer; Ralf Bennartz

2006-10-01T23:59:59.000Z

98

Improved Radiative Transfer Calculations from Information Provided by Bulk Microphysical Schemes  

Science Conference Proceedings (OSTI)

Bulk microphysical schemes are providing increasingly detailed information of hydrometeor profiles both within and below clouds. This information can be used to improve radiative transfer calculations with little increase in computation time. In ...

J. C. Petch

1998-05-01T23:59:59.000Z

99

Radiative Transfer on a Linear Lattice: Application to Anisotropic Ice Crystal Clouds  

Science Conference Proceedings (OSTI)

The problem of radiative transfer in a horizontally infinite cloud layer possessing anisotropy with respect to volume extinction and other single-scattering properties was solved using the method of discrete space theory. The model was applied to ...

Graeme L. Stephens

1980-09-01T23:59:59.000Z

100

The Spherical Harmonics Discrete Ordinate Method for Three-Dimensional Atmospheric Radiative Transfer  

Science Conference Proceedings (OSTI)

A new algorithm for modeling radiative transfer in inhomogeneous three-dimensional media is described. The spherical harmonics discrete ordinate method uses a spherical harmonic angular representation to reduce memory use and time computing the ...

K. Franklin Evans

1998-02-01T23:59:59.000Z

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.


101

Aircraft Observations of the Vertical Structure of Stratiform Precipitation Relevant to Microwave Radiative Transfer  

Science Conference Proceedings (OSTI)

The retrieval of rainfall intensity over the oceans from passive microwave observations is based on a radiative transfer model. Direct rainfall observations of oceanic rainfall are virtually nonexistent making validation of the retrievals ...

A. T. C. Chang; A. Barnes; M. Glass; R. Kakar; T. T. Wilheit

1993-06-01T23:59:59.000Z

102

Assessing 1D Atmospheric Solar Radiative Transfer Models: Interpretation and Handling of Unresolved Clouds  

Science Conference Proceedings (OSTI)

The primary purpose of this study is to assess the performance of 1D solar radiative transfer codes that are used currently both for research and in weather and climate models. Emphasis is on interpretation and handling of unresolved clouds. ...

H. W. Barker; G. L. Stephens; P. T. Partain; J. W. Bergman; B. Bonnel; K. Campana; E. E. Clothiaux; S. Clough; S. Cusack; J. Delamere; J. Edwards; K. F. Evans; Y. Fouquart; S. Freidenreich; V. Galin; Y. Hou; S. Kato; J. Li; E. Mlawer; J.-J. Morcrette; W. O'Hirok; P. Räisänen; V. Ramaswamy; B. Ritter; E. Rozanov; M. Schlesinger; K. Shibata; P. Sporyshev; Z. Sun; M. Wendisch; N. Wood; F. Yang

2003-08-01T23:59:59.000Z

103

The multiple absorption coefficient zonal method (MACZM), an efficient computational approach for the analysis of radiative heat transfer in multidimensional inhomogeneous nongray media  

E-Print Network (OSTI)

of Radiative Heat Transfer, the P-3 Approximation”, AIAAMedia”, Journal of Heat Transfer, Vol. 109, No. 3 (1987),Media”, Numerical Heat Transfer, Part B, Fundamentals, Vol.

Yuen, W W

2006-01-01T23:59:59.000Z

104

Change in regime and transfer function models of global solar radiation in Kuwait  

Science Conference Proceedings (OSTI)

The development of the models for global solar radiation in Kuwait is based on removing the annual periodicity and seasonal variation. The first methodology used here is the change in regime technique that relies on dividing the observations into two ... Keywords: ARMA model, Harmonic analysis, Solar radiation, Transfer function

S. A. Al-Awadhi

2005-09-01T23:59:59.000Z

105

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 Krüger; Giuseppe Bimonte; Thorsten Emig; Mehran Kardar

2012-07-02T23:59:59.000Z

106

Multimode Radiative Transfer in Finite Optical Media. II: Solutions  

Science Conference Proceedings (OSTI)

This paper extends the theoretical developments of Part I to illustrate the power of the method in solving multiple scattering problems with sources that result from i) the single scatter of a collimated beam of solar radiation that is directly ...

Graeme L. Stephens; Rudolph W. Preisendorfer

1984-03-01T23:59:59.000Z

107

Modeling heat conduction and radiation transport with the diffusion equation in  

NLE Websites -- All DOE Office Websites (Extended Search)

heat conduction and radiation transport with the diffusion equation in NIF ALE-AMR heat conduction and radiation transport with the diffusion equation in NIF ALE-AMR This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2010 J. Phys.: Conf. Ser. 244 022075 (http://iopscience.iop.org/1742-6596/244/2/022075) Download details: IP Address: 50.136.219.251 The article was downloaded on 18/04/2013 at 01:36 Please note that terms and conditions apply. View the table of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About Contact us My IOPscience Modeling Heat Conduction and Radiation Transport with the Diffusion Equation in NIF ALE-AMR A.C. Fisher 1 , D.S. Bailey 1 , T.B. Kaiser 1 , B.T.N. Gunney 1 , N.D. Masters 1 , A.E. Koniges 2 , D.C. Eder 1 , R.W. Anderson 1 1: Lawrence Livermore National Laboratory,

108

Radiative component and combined heat transfer in the thermal calculation of finned tube banks  

Science Conference Proceedings (OSTI)

For more exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heat flux was introduced. The applicability of this methods has been demonstrated on a tubular fired heater convective section. A developed computer program based on the method has also been used for an analysis of the influence of selected parameters to show the share of radiation on the total heat flux.

Stehlik, P. [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering] [Technical Univ. of Brno (Czech Republic). Dept. of Process Engineering

1999-01-01T23:59:59.000Z

109

A Systematic Study of Longwave Radiative Heating and Cooling within Valleys and Basins Using a Three-Dimensional Radiative Transfer Model  

Science Conference Proceedings (OSTI)

The Monte Carlo code for the physically correct tracing of photons in cloudy atmospheres (MYSTIC) three-dimensional radiative transfer model was used in a parametric study to determine the strength of longwave radiative heating and cooling in ...

Sebastian W. Hoch; C. David Whiteman; Bernhard Mayer

2011-12-01T23:59:59.000Z

110

The Influence of Radiative Transfer on the Mass and Heat Budgets of Ice Crystals Failing in the Atmosphere  

Science Conference Proceedings (OSTI)

A theoretical study was carried out to investigate the effect of radiative heating and cooling on the mass and heat budgets of an ice crystal. Equations describing the radiative budget of an ice crystal were derived and particle absorption ...

Graeme L. Stephens

1983-07-01T23:59:59.000Z

111

Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report  

Open Energy Info (EERE)

Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report Cross-Validation of SWERA's Core Radiative Transfer Models - Partial Report Dataset Summary Description (Abstract): This partial report describes the results obtained by two of the core radiative transfer models adopted in the SWERA Project for global horizontal solar irradiation during the cross-validation step. They are BRASIL-SR and SUNY-ALBANY models (Martins, 2001; Stuhlmann et al. 1990; Perez et al., 2002). The results from other two other core models, NREL and DLR, are not yet available. The HELIOSAT was included as a reference model at this stage. The HELIOSAT model is widely employed for solar energy assessment in Europe and is well know by the solar energy community worldwide (Beyer et al., 1996; Cano et al., 1986). (Purpose): SWERA solar cross-validation study

112

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

NLE Websites -- All DOE Office Websites (Extended Search)

Poisson Stochastic Radiative Transfer Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models T. B. Zhuravleva Institute of Atmospheric Optics Tomsk, Russia A. Marshak National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland Background Starting from a very simple stochastic cloud model by Mullamaa et al. (1972), several different stochastic models have been developed to describe radiative transfer regime in single-layer broken clouds (Kargin 1984; Titov 1990; Malvagi and Pomraning 1992; Barker et al. 1992; Malvagi et al. 1993; Kargin and Prigarin 1994; Prigarin and Titov 1996; Marshak et al. 1998; Prigarin et al. 1998, 2001; Evans et al. 1999, 2001). Recently Kassianov (2003a) generalized the Titov's (1990) stochastic model

113

Doubling–Adding Method for Delta-Four-Stream Spherical Harmonic Expansion Approximation in Radiative Transfer Parameterization  

Science Conference Proceedings (OSTI)

Though the single-layer solutions have been found for the ?-four-stream spherical harmonic expansion method (SHM) in radiative transfer, there is lack of a corresponding doubling–adding method (4SDA), which enables the calculation of radiative ...

Feng Zhang; Jiangnan Li

2013-10-01T23:59:59.000Z

114

paNTICA: A Fast 3D Radiative Transfer Scheme to Calculate Surface Solar Irradiance for NWP and LES Models  

Science Conference Proceedings (OSTI)

The resolution of numerical weather prediction models is constantly increasing, making it necessary to consider three-dimensional radiative transfer effects such as cloud shadows cast into neighboring grid cells and thus affecting radiative ...

Ulrike Wissmeier; Robert Buras; Bernhard Mayer

2013-08-01T23:59:59.000Z

115

Development and Evaluation of RRTMG_SW, a Shortwave Radiative Transfer Model for GCM Applications  

NLE Websites -- All DOE Office Websites (Extended Search)

Development and Evaluation of RRTMG_SW, Development and Evaluation of RRTMG_SW, a Shortwave Radiative Transfer Model for General Circulation Model Applications M. J. Iacono, J. S. Delamere, E. J. Mlawer, and S. A. Clough Atmospheric and Environmental Research, Inc. Lexington, Massachusetts J.-J. Morcrette European Center for Medium-Range Weather Forecasts Reading, United Kingdom Y.-T. Hou National Centers for Environmental Prediction Camp Springs, Maryland Introduction The k-distribution shortwave radiation model developed for the Atmospheric Radiation Measurement (ARM) Program, RRTM_SW_V2.4 (Clough et al. 2004), utilizes the discrete ordinates radiative transfer model, DISORT, for scattering calculations and 16 g-points in each of its 16 spectral bands. DISORT provides agreement with line-by-line flux calculations to within 1 Wm

116

A Comprehensive Radiation Scheme for Numerical Weather Prediction Models with Potential Applications in Climate Simulations  

Science Conference Proceedings (OSTI)

A comprehensive scheme for the parameterization of radiative transfer in numerical weather Prediction (NWP) models has been developed. The scheme is based on the solution of the ?-two-stream version of the radiative transfer equation ...

Bodo Ritter; Jean-Francois Geleyn

1992-02-01T23:59:59.000Z

117

A hybrid transport-diffusion method for Monte Carlo radiative-transfer simulations  

Science Conference Proceedings (OSTI)

Discrete Diffusion Monte Carlo (DDMC) is a technique for increasing the efficiency of Monte Carlo particle-transport simulations in diffusive media. If standard Monte Carlo is used in such media, particle histories will consist of many small steps, resulting ... Keywords: Hybrid transport-diffusion, Monte Carlo, Radiative transfer

Jeffery D. Densmore; Todd J. Urbatsch; Thomas M. Evans; Michael W. Buksas

2007-03-01T23:59:59.000Z

118

Radiative Transfer to Space through a Precipitating Cloud at Multiple Microwave Frequencies. Part I: Model Description  

Science Conference Proceedings (OSTI)

In a two-part study we investigate the impact of time-dependent cloud microphysical structure on the transfer to space of passive microwave radiation at several frequencies across the EHF and lower SHF portions of the microwave spectrum in order ...

Alberto Mugnai; Eric A. Smith

1988-09-01T23:59:59.000Z

119

Net Exchange Reformulation of Radiative Transfer in the CO2 15-?m Band on Mars  

Science Conference Proceedings (OSTI)

The net exchange formulation (NEF) is an alternative to the usual radiative transfer formulation. It was proposed by two authors in 1967, but until now, this formulation has been used only in a very few cases for atmospheric studies. The aim of ...

Jean-Louis Dufresne; Richard Fournier; Christophe Hourdin; Frédéric Hourdin

2005-09-01T23:59:59.000Z

120

A Computation of the Stratospheric Diabatic Circulation Using an Accurate Radiative Transfer Model  

Science Conference Proceedings (OSTI)

The global diabatic circulation is computed for the months of January, April, July and October over the altitude region 100 to 0.1 mb using an accurate troposphere-stratosphere radiative transfer model, SBUV and SME ozone data, and NMC ...

Joan E. Rosenfield; Mark R. Schoeberl; Marvin A. Geller

1987-03-01T23:59:59.000Z

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
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121

Analytic Green’s Function for Radiative Transfer in Plane-Parallel Atmospheres  

Science Conference Proceedings (OSTI)

Green’s function is a widely used approach for boundary value problems. In problems related to radiative transfer, Green’s function has been found to be useful in land, ocean, and atmosphere remote sensing. It is also a key element in higher ...

Yi Qin; Michael A. Box

2005-08-01T23:59:59.000Z

122

Physically Based Satellite Retrieval of Precipitation Using a 3D Passive Microwave Radiative Transfer Model  

Science Conference Proceedings (OSTI)

A precipitation retrieval algorithm based on the application of a 3D radiative transfer model to a hybrid physical-stochastic 3D cloud model is described. The cloud model uses a statistical rainfall clustering scheme to generate 3D cloud ...

J. L. Haferman; E. N. Anagnostou; D. Tsintikidis; W. F. Krajewski; T. F. Smith

1996-08-01T23:59:59.000Z

123

Intercomparison of Radiation Transfer Models Representing Direct Shortwave Forcing by Sulfate Aerosols  

E-Print Network (OSTI)

A study has been conducted, involving 15 models by 12 groups, to compare modeled forcing (change in shortwave radiation budget) due to sulfate aerosol for a wide range of values of particle radius, optical depth, surface albedo, and solar zenith angle (SZA). The models included high- and low-spectral resolution models, incorporating a variety of radiative transfer approximations, as well as a line-by-line model. The normalized forcings (forcing per sulfate column burden) obtained with the radiative transfer models were examined and the differences characterized. All models simulate forcings of comparable amplitude and exhibit a similar dependence on input parameters. As expected for a non-light-absorbing aerosol, forcings were negative (cooling influence), except at high surface albedo combined with low SZA. The relative standard deviation of the zenith-angle-average normalized broadband forcing for 15 models was 8% for particle radius near the maximum in magnitude of this forcing (ca....

Sulfate Aerosols; Stephen E Schwartz

1998-01-01T23:59:59.000Z

124

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

125

Energy transfer properties and absorption spectra of the FMO complex: from exact PIMC calculations to TCL master equations  

E-Print Network (OSTI)

We investigate the excitonic energy transfer (EET) in the Fenna-Matthews-Olsen complex and obtain the linear absorption spectrum (at 300 K) by a phenomenological time-convolutionless (TCL) master equation which is validated by utilizing Path Integral Monte Carlo (PIMC) simulations. By applying Marcus' theory for choosing the proper Lindblad operators for the long-time incoherent hopping process and using local non-Markovian dephasing rates, our model shows very good agreement with the PIMC results for EET. It also correctly reproduces the linear absorption spectrum that is found in experiment, without using any fitting parameters.

Schijven, Piet; Muelken, Oliver

2013-01-01T23:59:59.000Z

126

Energy transfer properties and absorption spectra of the FMO complex: from exact PIMC calculations to TCL master equations  

E-Print Network (OSTI)

We investigate the excitonic energy transfer (EET) in the Fenna-Matthews-Olsen complex and obtain the linear absorption spectrum (at 300 K) by a phenomenological time-convolutionless (TCL) master equation which is validated by utilizing Path Integral Monte Carlo (PIMC) simulations. By applying Marcus' theory for choosing the proper Lindblad operators for the long-time incoherent hopping process and using local non-Markovian dephasing rates, our model shows very good agreement with the PIMC results for EET. It also correctly reproduces the linear absorption spectrum that is found in experiment, without using any fitting parameters.

Piet Schijven; Lothar Muehlbacher; Oliver Muelken

2013-01-03T23:59:59.000Z

127

Formation of singularities in solutions to the compressible radiation hydrodynamics equations with vacuum  

E-Print Network (OSTI)

We study the Cauchy problem for multi-dimensional compressible radiation hydrodynamics equations with vacuum. First, we present some sufficient conditions on the blow-up of smooth solutions in multi-dimensional space. Then, we obtain the invariance of the support of density for the smooth solutions with compactly supported initial mass density by the property of the system under the vacuum state. Based on the above-mentioned results, we prove that we cannot get a global classical solution, no matter how small the initial data are, as long as the initial mass density is of compact support. Finally, we will see that some of the results that we obtained are still valid for the isentropic flows with degenerate viscosity coefficients as well as 1-D case.

Yachun Li; Shengguo Zhu

2013-09-28T23:59:59.000Z

128

Estimates for Infrared Transfer in Finite Clouds  

Science Conference Proceedings (OSTI)

Upper and lower bounds are computed for the infrared radiance within a cloud of finite size. The bounds are established by an iterative procedure, analogous to the iterative solution of the radiative transfer equation, except that at every ...

D. M. O'Brien

1986-02-01T23:59:59.000Z

129

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.

Biehs, Svend-Age

2011-01-01T23:59:59.000Z

130

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

131

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

132

Radiative equilibrium in Monte Carlo radiative transfer using frequency distribution adjustment  

E-Print Network (OSTI)

The Monte Carlo method is a powerful tool for performing radiative equilibrium calculations, even in complex geometries. The main drawback of the standard Monte Carlo radiative equilibrium methods is that they require iteration, which makes them numerically very demanding. Bjorkman & Wood recently proposed a frequency distribution adjustment scheme, which allows radiative equilibrium Monte Carlo calculations to be performed without iteration, by choosing the frequency of each re-emitted photon such that it corrects for the incorrect spectrum of the previously re-emitted photons. Although the method appears to yield correct results, we argue that its theoretical basis is not completely transparent, and that it is not completely clear whether this technique is an exact rigorous method, or whether it is just a good and convenient approximation. We critically study the general problem of how an already sampled distribution can be adjusted to a new distribution by adding data points sampled from an adjustment distribution. We show that this adjustment is not always possible, and that it depends on the shape of the original and desired distributions, as well as on the relative number of data points that can be added. Applying this theorem to radiative equilibrium Monte Carlo calculations, we provide a firm theoretical basis for the frequency distribution adjustment method of Bjorkman & Wood, and we demonstrate that this method provides the correct frequency distribution through the additional requirement of radiative equilibrium. We discuss the advantages and limitations of this approach, and show that it can easily be combined with the presence of additional heating sources and the concept of photon weighting. However, the method may fail if small dust grains are included... (abridged)

Maarten Baes; Dimitris Stamatellos; Jonathan I. Davies; Anthony P. Whitworth; Sabina Sabatini; Sarah Roberts; Suzanne M. Linder; Rhodri Evans

2005-04-01T23:59:59.000Z

133

Thermal correction to the Casimir force, radiative heat transfer, and an experiment  

E-Print Network (OSTI)

The low-temperature asymptotic expressions for the Casimir interaction between two real metals described by Leontovich surface impedance are obtained in the framework of thermal quantum field theory. It is shown that the Casimir entropy computed using the impedance of infrared optics vanishes in the limit of zero temperature. By contrast, the Casimir entropy computed using the impedance of the Drude model attains at zero temperature a positive value which depends on the parameters of a system, i.e., the Nernst heat theorem is violated. Thus, the impedance of infrared optics withstands the thermodynamic test, whereas the impedance of the Drude model does not. We also perform a phenomenological analysis of the thermal Casimir force and of the radiative heat transfer through a vacuum gap between real metal plates. The characterization of a metal by means of the Leontovich impedance of the Drude model is shown to be inconsistent with experiment at separations of a few hundred nanometers. A modification of the impedance of infrared optics is suggested taking into account relaxation processes. The power of radiative heat transfer predicted from this impedance is several times less than previous predictions due to different contributions from the transverse electric evanescent waves. The physical meaning of low frequencies in the Lifshitz formula is discussed. It is concluded that new measurements of radiative heat transfer are required to find out the adequate description of a metal in the theory of electromagnetic fluctuations.

V. B. Bezerra; G. Bimonte; G. L. Klimchitskaya; V. M. Mostepanenko; C. Romero

2007-08-18T23:59:59.000Z

134

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

Science Conference Proceedings (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

135

COLLAPSE OF MOLECULAR CLOUD CORES WITH RADIATION TRANSFER: FORMATION OF MASSIVE STARS BY ACCRETION  

Science Conference Proceedings (OSTI)

Most early radiative transfer calculations of protostellar collapse have suggested an upper limit of approx40 M{sub sun} for the final stellar mass before radiation pressure can exceed the star's gravitational pull and halt the accretion. Here we perform further collapse calculations, using frequency-dependent radiation transfer coupled to a frequency-dependent dust model that includes amorphous carbon particles, silicates, and ice-coated silicates. The models start from pressure-bounded, logatropic spheres of mass between 5 M{sub sun} and 150 M{sub sun} with an initial nonsingular density profile. We find that in a logatrope the infall is never reversed by the radiative forces on the dust and that stars with masses approx>100 M{sub sun} may form by continued accretion. Compared to previous models that start the collapse with a rho propor to r{sup -2} density configuration, our calculations result in higher accretion times and lower average accretion rates with peak values of approx5.8 x 10{sup -5} M{sub sun} yr{sup -1}. The radii and bolometric luminosities of the produced massive stars (approx>90 M{sub sun}) are in good agreement with the figures reported for detected stars with initial masses in excess of 100 M{sub sun}. The spectral energy distribution from the stellar photosphere reproduces the observed fluxes for hot molecular cores with peaks of emission from mid- to near-infrared.

Sigalotti, Leonardo Di G.; Daza-Montero, Judith [Centro de Fisica, Instituto Venezolano de Investigaciones CientIficas, IVIC, Apartado 21827, Caracas 1020A (Venezuela, Bolivarian Republic of); De Felice, Fernando [Dipartimento di Fisica 'G. Galilei', Universita di Padova, Via Marzolo 8 35131 Padova (Italy)

2009-12-20T23:59:59.000Z

136

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; Castaño, Gabriel

2012-01-01T23:59:59.000Z

137

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

2010-12-20T23:59:59.000Z

138

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

E-Print Network (OSTI)

We develop a general numerical method to calculate the nonequilibrium radiative heat transfer between a plate and compact objects of arbitrary shapes, making the first accurate theoretical predictions for the total heat ...

McCauley, Alexander Patrick

139

An Assessment of the Parameterization of Subgrid-Scale Cloud Effects on Radiative Transfer. Part II: Horizontal Inhomogeneity  

Science Conference Proceedings (OSTI)

The role of horizontal inhomogeneity in radiative transfer through cloud fields is investigated within the context of the two-stream approximation. Spatial correlations between cloud optical properties and the radiance field are introduced in the ...

Norman B. Wood; Philip M. Gabriel; Graeme L. Stephens

2005-08-01T23:59:59.000Z

140

Global Calibration of the GEOS-5 L-Band Microwave Radiative Transfer Model over Nonfrozen Land Using SMOS Observations  

Science Conference Proceedings (OSTI)

A zero-order (tau-omega) microwave radiative transfer model (RTM) is coupled to the Goddard Earth Observing System, version 5 (GEOS-5) catchment land surface model in preparation for the future assimilation of global brightness temperatures (Tb) ...

Gabriëlle J. M. De Lannoy; Rolf H. Reichle; Valentijn R. N. Pauwels

2013-06-01T23:59:59.000Z

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.


141

Retrieval of Sea Surface Temperature from Space, Based on Modeling of Infrared Radiative Transfer: Capabilities and Limitations  

Science Conference Proceedings (OSTI)

The retrieval (estimation) of sea surface temperatures (SSTs) from space-based infrared observations is increasingly performed using retrieval coefficients derived from radiative transfer simulations of top-of-atmosphere brightness temperatures (...

Christopher J. Merchant; Pierre Le Borgne

2004-11-01T23:59:59.000Z

142

The Gastropod Fast Radiative Transfer Model for Advanced Infrared Sounders and Characterization of Its Errors for Radiance Assimilation  

Science Conference Proceedings (OSTI)

Principal aspects of the development of Gastropod, a fixed-pressure-grid fast radiative transfer model for the Atmospheric Infrared Sounder (AIRS), are described. Performance of the forward and gradient operators is characterized, and the impact ...

V. Sherlock; A. Collard; S. Hannon; R. Saunders

2003-12-01T23:59:59.000Z

143

Microweve Radiative Transfer through Clouds Composed of Realistically Shaped Ice Crystals. Part II. Remote Sensing of Ice Clouds  

Science Conference Proceedings (OSTI)

This paper presents the results of polarized microwave radiative transfer modeling of cirrus clouds containing five different particle shoes and 18 Gamma size distributions. Upwelling brightness temperatures for tropical and midlatitude winter ...

K. Franklin Evans; Graeme L. Stephens

1995-06-01T23:59:59.000Z

144

The Full-Spectrum Correlated-k Method for Longwave Atmospheric Radiative Transfer Using an Effective Planck Function  

Science Conference Proceedings (OSTI)

The correlated-k-distribution (CKD) method is widely used in the radiative transfer schemes of atmospheric models; it involves dividing the spectrum into a number of bands and then reordering the gaseous absorption coefficients within each one. ...

Robin J. Hogan

2010-06-01T23:59:59.000Z

145

Computational Cost and Accuracy in Calculating Three-Dimensional Radiative Transfer: Results for New Implementations of Monte Carlo and SHDOM  

Science Conference Proceedings (OSTI)

This paper examines the tradeoffs between computational cost and accuracy for two new state-of-the-art codes for computing three-dimensional radiative transfer: a community Monte Carlo model and a parallel implementation of the Spherical ...

Robert Pincus; K. Franklin Evans

2009-10-01T23:59:59.000Z

146

Monte Carlo simulation of radiation heat transfer in arrays of fixed discrete surfaces using cell-to-cell photon transport  

DOE Green Energy (OSTI)

Radiation heat transfer in an array of fixed discrete surfaces is an important problem that is particularly difficult to analyze because of the nonhomogeneous and anisotropic optical properties involved. This article presents an efficient Monte Carlo method for evaluating radiation heat transfer in arrays of fixed discrete surfaces. This Monte Carlo model has been optimized to take advantage of the regular arrangement of surfaces often encountered in these arrays. Monte Carlo model predictions have been compared with analytical and experimental results.

Drost, M.K. (Pacific Northwest Lab., Richland, WA (United States)); Welty, J.R. (Oregon State Univ., Corvallis, OR (United States))

1992-08-01T23:59:59.000Z

147

Variable order spherical harmonic expansion scheme for the radiative transport equation using finite elements  

SciTech Connect

Highlights: {yields} We developed a variable order global basis scheme to solve light transport in 3D. {yields} Based on finite elements, the method can be applied to a wide class of geometries. {yields} It is computationally cheap when compared to the fixed order scheme. {yields} Comparisons with local basis method and other models demonstrate its accuracy. {yields} Addresses problems encountered n modeling of light transport in human brain. - Abstract: We propose the P{sub N} approximation based on a finite element framework for solving the radiative transport equation with optical tomography as the primary application area. The key idea is to employ a variable order spherical harmonic expansion for angular discretization based on the proximity to the source and the local scattering coefficient. The proposed scheme is shown to be computationally efficient compared to employing homogeneously high orders of expansion everywhere in the domain. In addition the numerical method is shown to accurately describe the void regions encountered in the forward modeling of real-life specimens such as infant brains. The accuracy of the method is demonstrated over three model problems where the P{sub N} approximation is compared against Monte Carlo simulations and other state-of-the-art methods.

Surya Mohan, P., E-mail: sprerapa@cs.ucl.ac.uk [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Tarvainen, Tanja, E-mail: tanja.tarvainen@uef.fi [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio (Finland); Schweiger, Martin, E-mail: martins@medphys.ucl.ac.uk [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Pulkkinen, Aki, E-mail: pulkkine@sten.sunnybrook.utoronto.ca [Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio (Finland); Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, M4N 3M5 (Canada); Arridge, Simon R., E-mail: S.Arridge@cs.ucl.ac.uk [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2011-08-10T23:59:59.000Z

148

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

E-Print Network (OSTI)

Current physically-based Radiative Transfer Model (RTM) algorithms for estimating oceanic rain use a very simplified hydrometeor profile that ignores the mixed-phase regions (Wilheit et al., 1977). However, to estimate hydrometeor profiles more reasonably in the tropical precipitation regions, understanding of the brightness temperature (Tb) variations in the mixed-phase regions is essential. Further, establishing physical assumptions for microwave radiative transfer in the mixed-phase regions is necessary for quantifying and minimizing the uncertainties in the rainfall retrieval. Consequently, the objective of this study was to quantify uncertainties and to achieve a solid basis for improvement of the current rainfall retrieval, which is based 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 data and aircraft microphysics data. Analyses were performed for the stratiform and convective rainfall regions respectively. In stratiform precipitation with a bright band, the main concern was to examine the needed physical assumptions for describing the abrupt change of Tb just below the freezing level. In the case of convective precipitation, the focus was to investigate the effective additional rain layer thickness corresponding to the super-cooled water layer above the freezing level. From the results, it was required to assume the bright-band (around 1/2 km below the FL) as having 2 times the absorption as the rain below to explain the Tb variation due to the phase change of hydrometeors. On the other hand, in the case of convective rainfall, it was suggested that approximately from 1/4km to 3km of super-cooled layer thickness should be considered to describe the additional hydrometeor layer due to the strong updrafts in the convective regions.

Jin, Kyoung-Wook

2001-01-01T23:59:59.000Z

149

Using radiative transfer equation to model absorption by thin Cu(In,Ga)Se2  

E-Print Network (OSTI)

on Photovoltaic Energy Conversion, K. Kurokawa ed. (Arisumi, Osaka, Japan, 2003), pp. 344­347. 10. F. Leblanc, J European Photovoltaic Solar Energy Conference, James & James ed. (Alden, Glasgow, UK, 2000), pp. 522 thin film silicon solar cells: optical model," in 16th European Photovoltaic Solar Energy Conference

150

Non-Markovian Second-Order Quantum Master Equation and Its Markovian Limit: Electronic Energy Transfer in Model Photosynthetic Systems  

E-Print Network (OSTI)

A direct numerical algorithm for solving the time-nonlocal non-Markovian master equation in the second Born approximation is introduced and the range of utility of this approximation, and of the Markov approximation, is analyzed for the traditional dimer system that models excitation energy transfer in photosynthesis. Specifically, the coupled integro-differential equations for the reduced density matrix are solved by an efficient auxiliary function method in both the energy and site representations. In addition to giving exact results to this order, the approach allows us to computationally assess the range of the reorganization energy and decay rates of the phonon auto-correlation function for which the Markovian Redfield theory and the second order approximation is valid. For example, the use of Redfield theory for $\\lambda> 10 \\textrm{cm}^{-1}$ in systems like Fenna-Mathews-Olson (FMO) type systems is shown to be in error. In addition, analytic inequalities are obtained for the regime of validity of the Markov approximation in cases of weak and strong resonance coupling, allowing for a quick determination of the utility of the Markovian dynamics in parameter regions. Finally, results for the evolution of states in a dimer system, with and without initial coherence, are compared in order to assess the role of initial coherences.

Navinder Singh; Paul Brumer

2011-06-29T23:59:59.000Z

151

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. Guérout; F. S. S. Rosa; J. -J. Greffet; A. Lambrecht; S. Reynaud

2012-06-01T23:59:59.000Z

152

TAU: A 1D radiative transfer code for transmission spectroscopy of extrasolar planet atmospheres  

E-Print Network (OSTI)

The TAU code is a 1D line-by-line radiative transfer code, which is generally applicable for modelling transmission spectra of close-in extrasolar planets. The inputs are the assumed pressure-temperature profile of the planetary atmosphere, the continuum absorption coefficients and the absorption cross-sections for the trace molecular absorbers present in the model, as well as the fundamental system parameters taken from the published literature. The program then calculates the optical path through the planetary atmosphere of the radiation from the host star, and quantifies the absorption due to the modelled composition in a transmission spectrum of transit depth as a function of wavelength. The code is written in C++, parallelised using OpenMP, and is available for public download and use from http://www.ucl.ac.uk/exoplanets/.

Hollis, M D J; Tinetti, G

2013-01-01T23:59:59.000Z

153

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

SciTech Connect

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

154

Computation of Domain-Averaged Irradiance with a Simple Two-Stream Radiative Transfer Model Including Vertical Cloud Property Correlations  

NLE Websites -- All DOE Office Websites (Extended Search)

Computation of Domain-Averaged Irradiance Computation of Domain-Averaged Irradiance with a Simple Two-Stream Radiative Transfer Model Including Vertical Cloud Property Correlations S. Kato Center for Atmospheric Sciences Hampton University Hampton, Virginia Introduction Recent development of remote sensing instruments by Atmospheric Radiation Measurement (ARM?) Program provides information of spatial and temporal variability of cloud structures. However it is not clear what cloud properties are required to express complicated cloud fields in a realistic way and how to use them in a relatively simple one-dimensional (1D) radiative transfer model to compute the domain averaged irradiance. To address this issue, a simple shortwave radiative transfer model that can treat the vertical cloud optical property correlation is developed. The model is based on the gamma-weighted

155

Implementation of a simplified approach to radiative transfer in general relativity  

E-Print Network (OSTI)

We describe in detail the implementation of a simplified approach to radiative transfer in general relativity by means of the well-known neutrino leakage scheme (NLS). In particular, we carry out an extensive investigation of the properties and limitations of the NLS for isolated relativistic stars to a level of detail that has not been discussed before in a general-relativistic context. Although the numerous tests considered here are rather idealized, they provide a well-controlled environment in which to understand the relationship between the matter dynamics and the neutrino emission, which is important in order to model the neutrino signals from more complicated scenarios, such as binary neutron-star mergers. When considering nonrotating hot neutron stars we confirm earlier results of one-dimensional simulations, but also present novel results about the equilibrium properties and on how the cooling affects the stability of these configurations. In our idealized but controlled setup, we can then show that deviations from the thermal and weak-interaction equilibrium affect the stability of these models to radial perturbations, leading models that are stable in the absence of radiative losses, to a gravitational collapse to a black hole when neutrinos are instead radiated.

Filippo Galeazzi; Wolfgang Kastaun; Luciano Rezzolla; José A. Font

2013-06-20T23:59:59.000Z

156

The Angular Distribution of UV-B Sky Radiance under Cloudy Conditions: A Comparison of Measurements and Radiative Transfer Calculations Using a Fractal Cloud Model  

Science Conference Proceedings (OSTI)

In recent years, global warming concerns have focused attention on cloud radiative forcing and its accurate encapsulation in radiative transfer measurement and modeling programs. At present, this process is constrained by the dynamic movement and ...

Christopher Kuchinke; Kurt Fienberg; Manuel Nunez

2004-05-01T23:59:59.000Z

157

Thermal-radiation heat-transfer model for degraded cores. [PWR; BWR  

SciTech Connect

One consequence of the accident at the Three Mile Island Unit 2 (TMI-2) nuclear power plant is a realization by the nuclear power technical community that there is a need for calculational tools that can be used to analyze the TMI-2 accident and to investigate hypothetical situations involving degraded light-water reactor (LWR) cores. As a result, there are now several ongoing modeling and code development efforts in the United States among which is the development of the MIMAS (Multifield Integrated Meltdown Analysis System code) at the Los Alamos National Laboratory. This paper describes a thermal-radiation heat-transfer model for LWR degraded cores that has been developed for the MIMAS code.

Tomkins, J.L.

1983-01-01T23:59:59.000Z

158

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

SciTech Connect

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

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

SciTech Connect

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

160

Three-dimensional dust radiative-transfer models: The Pinwheel Nebula of WR104  

E-Print Network (OSTI)

We present radiative-transfer modelling of the dusty spiral Pinwheel Nebula observed around the Wolf-Rayet/OB-star binary WR104. The models are based on the three-dimensional radiative-transfer code TORUS, modified to include an adaptive mesh that allows us to adequately resolve both the inner spiral turns (sub-AU scales) and the outer regions of the nebula (distances of 10^4 AU from the central source). The spiral model provides a good fit to both the spectral energy distribution and Keck aperture masking interferometry, reproducing both the maximum entropy recovered images and the visibility curves. We deduce a dust creation rate of 8+-1 x 10^{-7} solar masses per year, corresponding to approximately 2% by mass of the carbon produced by the Wolf-Rayet star. Simultaneous modelling of the imaging and spectral data enables us to constrain both the opening-angle of the wind-wind collision interface and the dust grain size. We conclude that the dust grains in the inner part of the Pinwheel nebula are small (~100A), in agreement with theoretical predictions, although we cannot rule out the presence of larger grains (~1 micron) further from the central binary. The opening angle of the wind-wind collision interface appears to be about 40 degrees, in broad agreement with the wind parameters estimated for the central binary. We discuss the success and deficiencies of the model, and the likely benefits of applying similar techniques to the more the more complex nebulae observed around other WR/O star binaries.

Tim J Harries; John D Monnier; Neil H Symington; Ryuichi Kurosawa

2004-01-27T23:59:59.000Z

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161

O Star X-ray Line Profiles Explained by Radiation Transfer in Inhomogeneous Stellar Wind  

E-Print Network (OSTI)

It is commonly adopted that X-rays from O stars are produced deep inside the stellar wind, and transported outwards through the bulk of the expanding matter which attenuates the radiation and affects the shape of emission line profiles. The ability of Chandra and XMM-Newton to resolve these lines spectroscopically provided a stringent test for the theory of X-ray production. It turned out that none of the existing models was able to reproduce the observations consistently. The major caveat of these models was the underlying assumption of a smooth stellar wind. Motivated by the various observational evidence that the stellar winds are in fact structured, we present a 2-D model of a stochastic, inhomogeneous wind. The X-ray radiative transfer is derived for such media. It is shown that profiles from a clumped wind differ drastically from those predicted by conventional homogeneous models. We review the up-to-date observations of X-ray line profiles from stellar winds and present line fits obtained from the inhomogeneous wind model. The necessity to account for inhomogeneities in calculating the X-ray transport in massive star winds, including for HMXB is highlighted.

L. M. Oskinova; A. Feldmeier; W. -R. Hamann

2005-11-01T23:59:59.000Z

162

The Effect of Tropospheric Aerosols on the Earth's Radiation Budget: A Parameterization for Climate Models  

Science Conference Proceedings (OSTI)

Guided by the results of doubling-adding solutions to the equation of radiative transfer, we develop a simple technique for incorporating in climate models the effect of the background tropospheric aerosol on solar radiation. Because the ...

James A. Coakley Jr.; Robert D. Cess; Franz B. Yurevich

1983-01-01T23:59:59.000Z

163

Simulating 3-D Radiative Transfer Effects over the Sierra Nevada Mountains using WRF  

Science Conference Proceedings (OSTI)

A surface solar radiation parameterization based on deviations between 3-D and conventional plane-parallel radiative transfer models has been incorporated into the Weather Research and Forecasting (WRF) model to understand the solar insolation over mountain/snow areas and to investigate the impact of the spatial and temporal distribution and variation of surface solar fluxes on land-surface processes. Using the Sierra-Nevada in the western United States as a testbed, we show that mountain effect could produce up to ?50 to + 50Wm?2 deviations in the surface solar fluxes over the mountain areas, resulting in a temperature increase of up to 1 °C on the sunny side. Upward surface sensible and latent heat fluxes are modulated accordingly to compensate for the change in surface solar fluxes. Snow water equivalent and surface albedo both show decreases on the sunny side of the mountains, indicating more snowmelt and hence reduced snow albedo associated with more solar insolation due to mountain effect. Soil moisture increases on the sunny side of the mountains due to enhanced snowmelt, while decreases on the shaded side. Substantial differences are found in the morning hours from 8-10 a.m. and in the afternoon around 3-5 p.m., while differences around noon and in the early morning and late afternoon are comparatively smaller. Variation in the surface energy balance can also affect atmospheric processes, such as cloud fields, through the modulation of vertical thermal structure. Negative changes of up to ?40 gm?2 are found in the cloud water path, associated with reductions in the surface insolation over the cloud region. The day-averaged deviations in the surface solar flux are positive over the mountain areas and negative in the valleys, with a range between ?12~12Wm?2. Changes in sensible and latent heat fluxes and surface skin temperature follow the solar insolation pattern. Differences in the domain-averaged diurnal variation over the Sierras show that the mountain area receives more solar insolation during early morning and late afternoon, resulting in enhanced upward sensible heat and latent heat fluxes from the surface and a corresponding increase in surface skin temperature. During the middle of the day, however, the surface insolation and heat fluxes show negative changes, indicating a cooling effect. Hence overall, the diurnal variations of surface temperature and surface fluxes in the Sierra-Nevada are reduced through the interactions of radiative transfer and mountains. The hourly differences of the surface solar insolation in higher elevated regions, however, show smaller magnitude in negative changes during the middle of the day and possibly more solar fluxes received during the whole day.

Gu, Yu; Liou, K. N.; Lee, W- L.; Leung, Lai-Yung R.

2012-10-30T23:59:59.000Z

164

Pioneering remote sensing in the USSR. 1. Radiation transfer in the optical wavelength region of the electromagnetic spectrum  

Science Conference Proceedings (OSTI)

In this paper a review is presented of the pioneering space research carried out under the leadership of Professor K. Ya. Kondratyev and with his direct participation. Some of his work concerned with radiation transfer in the atmosphere and with remote ...

T. A. Sushkevich

2008-05-01T23:59:59.000Z

165

A Discrete Ordinate, Multiple Scattering, Radiative Transfer Model of the Venus Atmosphere from 0.1 to 260 ?m  

Science Conference Proceedings (OSTI)

The authors describe a new radiative transfer model of the Venus atmosphere (RTM) that includes optical properties from nine gases and four cloud modes between 0.1 and 260 ?m. A multiple-stream discrete ordinate flux solver is used to calculate ...

Christopher Lee; Mark Ian Richardson

2011-06-01T23:59:59.000Z

166

Technical assessment of the prevention of micro-fouling on OTEC heat-transfer surfaces through the use of ultraviolet radiation  

DOE Green Energy (OSTI)

To reduce or eliminate biofouling by microorganisms it has been suggested that the seawater entering the heat exchanger be sterilized (or at least sanitized) by uv radiation at 253.7 nm. The feasibility of applying this technology to OTEC is examined. Trivial calculations based on the Lambert-Beer equation and reasonable assumptions about seawater quality and the intensity of irradiation obtainable from a uv lamp suggest seawater may be transparent enough to a collimated beam of uv light to deliver effective germicidal doses to nearly 150 cm under some conditions. However, the practical limit on the depth of effective radiation from commercial lamps is severely restricted by many factors including the natural divergence of light, absorption and scattering in the media, intensity of radiation from the light source and so forth. Even under very favorable conditions a common design allowing uv light to penetrate 30 cm of water would have to permit the water at that distance to be in contact with the light for 20 seconds or so to deliver the germicidal effect of high quality sanitization but not necessarily sterilization. Macro-fouling, which may be more severe than micro-fouling, will not be affected by uv radiation (presuming an absence of symbiotic relationships). Parasitic power required for uv sources may be prohibitive under unfavorable conditions (i.e., unexpectedly high absorptivities of seawater, or excessive turbidity) or the absence of an industrial effort to scale up present uv equipment appropriate to OTEC needs. This latter event is unlikely for it appears that present uv lamps can be adapted to OTEC needs without major technological advancement. Power and cost estimates for uv installation and operation vary widely depending on the number of lamps needed for the OTEC configuration and the intensity of uv radiation actually required to prevent biofouling of heat transfer systems in OTEC designs.

Garrigan, G. A.; Schmitt, R. P.; Ciccone, V. J.

1981-09-01T23:59:59.000Z

167

Impact of Changes to the Radiation Transfer Parameterizations Plus Cloud Optical. Properties in the ECMWF Model  

Science Conference Proceedings (OSTI)

A new radiation package, shown to correct most of the systematic errors of the operational ECMWF radiation scheme, has been extensively tested in the ECMWF forecast model. Improvements in the clear-sky fluxes and radiative heating/cooling rate ...

Jean-Jacques Morcrette

1990-04-01T23:59:59.000Z

168

3-D Radiative Transfer Modeling of Structured Winds in Massive Hot Stars with Wind3D  

E-Print Network (OSTI)

We develop 3-D models of the structured winds of massive hot stars with the Wind3D radiative transfer (RT) code. We investigate the physical properties of large-scale structures observed in the wind of the B-type supergiant HD 64760 with detailed line profile fits to Discrete Absorption Components (DACs) and rotational modulations observed with IUE in Si IV {\\lambda}1395. We develop parameterized input models Wind3D with large-scale equatorial wind density- and velocity-structures, or so-called `Co-rotating Interaction Regions' (CIRs) and `Rotational Modulation Regions' (RMRs). The parameterized models offer important advantages for high-performance RT calculations over ab-initio hydrodynamic input models. The acceleration of the input model calculations permits us to simulate and investigate a wide variety of physical conditions in the extended winds of massive hot stars. The new modeling method is very flexible for constraining the dynamic and geometric wind properties of RMRs in HD 64760. We compute that t...

Lobel, A; Blomme, R

2010-01-01T23:59:59.000Z

169

Investigation of Thin Cirrus Cloud Optical and Microphysical Properties on the Basis of Satellite Observations and Fast Radiative Transfer Models  

E-Print Network (OSTI)

This dissertation focuses on the global investigation of optically thin cirrus cloud optical thickness (tau) and microphysical properties, such as, effective particle size (D_(eff)) and ice crystal habits (shapes), based on the global satellite observations and fast radiative transfer models (RTMs). In the first part, we develop two computationally efficient RTMs simulating satellite observations under cloudy-sky conditions in the visible/shortwave infrared (VIS/SWIR) and thermal inferred (IR) spectral regions, respectively. To mitigate the computational burden associated with absorption, thermal emission and multiple scattering, we generate pre-computed lookup tables (LUTs) using two rigorous models, i.e., the line-by-line radiative transfer model (LBLRTM) and the discrete ordinates radiative transfer model (DISORT). The second part introduces two methods (i.e., VIS/SWIR- and IR-based methods) to retrieve tau and D_(eff) from satellite observations in corresponding spectral regions of the two RTMs. We discuss the advantages and weakness of the two methods by estimating the impacts from different error sources on the retrievals through sensitivity studies. Finally, we develop a new method to infer the scattering phase functions of optically thin cirrus clouds in a water vapor absorption channel (1.38-µm). We estimate the ice crystal habits and surface structures by comparing the inferred scattering phase functions and numerically simulated phase functions calculated using idealized habits.

Wang, Chenxi

2013-08-01T23:59:59.000Z

170

Vertical Profiles of Aerosol and Radiation and the Influence of a Temperature Inversion: Measurements and Radiative Transfer Calculations  

Science Conference Proceedings (OSTI)

The results of an airborne experiment performed near Mönchengladbach (Germany) in November 1993 are reported. Besides meteorological data, vertical profiles of aerosol properties (number concentration, size distribution) and radiation (...

M. Wendisch; S. Mertes; A. Ruggaber; T. Nakajima

1996-10-01T23:59:59.000Z

171

Improved Simulation of Clear-Sky Shortwave Radiative Transfer in the CCC-GCM  

Science Conference Proceedings (OSTI)

The disposition of mean July clear-sky solar radiation in the Canadian Climate Centre second-generation general circulation model (CCC-GCMII) was analyzed by comparing top of the atmosphere (TOA) net fluxes with earth radiation budget experiment (...

Howard W. Barker; Zhanqing Li

1995-09-01T23:59:59.000Z

172

Comparison between two common collocation approaches based on radial basis functions for the case of heat transfer equations arising in porous medium  

E-Print Network (OSTI)

In this paper two common collocation approaches based on radial basis functions have been considered; one be computed through the integration process (IRBF) and one be computed through the differentiation process (DRBF). We investigated the two approaches on natural convection heat transfer equations embedded in porous medium which are of great importance in the design of canisters for nuclear wastes disposal. Numerical results show that the IRBF be performed much better than the common DRBF, and show good accuracy and high rate of convergence of IRBF process.

K. Parand; S. Abbasbandy; S. Kazem; A. R. Rezaei

2010-08-13T23:59:59.000Z

173

Comparison between two common collocation approaches based on radial basis functions for the case of heat transfer equations arising in porous medium  

E-Print Network (OSTI)

In this paper two common collocation approaches based on radial basis functions have been considered; one be computed through the integration process (IRBF) and one be computed through the differentiation process (DRBF). We investigated the two approaches on natural convection heat transfer equations embedded in porous medium which are of great importance in the design of canisters for nuclear wastes disposal. Numerical results show that the IRBF be performed much better than the common DRBF, and show good accuracy and high rate of convergence of IRBF process.

Parand, K; Kazem, S; Rezaei, A R; 10.1016/j.cnsns.2010.07.011

2010-01-01T23:59:59.000Z

174

Using a Parameterization of a Radiative Transfer Model to Build High-Resolution Maps of Typical Clear-Sky UV Index in Catalonia, Spain  

Science Conference Proceedings (OSTI)

To perform a climatic analysis of the annual UV index (UVI) variations in Catalonia, Spain (northeast of the Iberian Peninsula), a new simple parameterization scheme is presented based on a multilayer radiative transfer model. The ...

Jordi Badosa; Josep-Abel González; Josep Calbó; Michiel van Weele; Richard L. McKenzie

2005-06-01T23:59:59.000Z

175

A faster algorithm for smoothed particle hydrodynamics with radiative transfer in the flux-limited diffusion approximation  

E-Print Network (OSTI)

We describe a new, faster implicit algorithm for solving the radiation hydrodynamics equations in the flux-limited diffusion approximation for smoothed particle hydrodynamics. This improves on the method elucidated in Whitehouse & Bate by using a Gauss-Seidel iterative method rather than iterating over the exchange of energy between pairs of particles. The new algorithm is typically many thousands of times faster than the old one, which will enable more complex problems to be solved. The new algorithm is tested using the same tests performed by Turner & Stone for ZEUS-2D, and repeated by Whitehouse & Bate.

Stuart C. Whitehouse; Matthew R. Bate; Joe J. Monaghan

2005-09-28T23:59:59.000Z

176

A scattering approach to Casimir forces and radiative heat transfer for nanostructured surfaces out of thermal equilibrium  

E-Print Network (OSTI)

We develop an exact method for computing Casimir forces and the power of radiative heat transfer between two arbitrary nanostructured surfaces out of thermal equilibrium. The method is based on a generalization of the scattering approach recently used in investigations on the Casimir effect. Analogously to the equilibrium case, we find that also out of thermal equilibrium the shape and composition of the surfaces enter only through their scattering matrices. The expressions derived provide exact results in terms of the scattering matrices of the intervening surfaces.

Giuseppe Bimonte

2009-09-11T23:59:59.000Z

177

Report of a workshop on the impact of chemicals on the radiative transfer imbalance  

SciTech Connect

This workshop delineates the significant factors, possessed by any chemical, that may directly or indirectly affect the radiation balance of the atmosphere. Atmospheric physics research has already given information on direct and indirect effects. An example of direct effect is the cumulative infrared greenhouse effect of several trace gases, some of which are anthropogenic, and the short wave radiative effects of unactivated aerosol particles in clouds. Examples of indirect effects are those of aerosols as they change cloud droplet size distributions and hence albedo and radiative properties, and as found in observations of albedo and absorption anomalies in clouds, and cloud modification by urban pollution. 26 references.

DeLuisi, J.J. (ed.)

1979-01-01T23:59:59.000Z

178

Parameterization of Atmospheric Radiative Transfer. Part I: Validity of Simple Models  

Science Conference Proceedings (OSTI)

This paper outlines a radiation parameterization method for deriving broadband fluxes that is currently being implemented in a number of global and regional atmospheric models. The rationale for the use of the 2-stream method as a way of solving ...

Graeme L. Stephens; Philip M. Gabriel; Philip T. Partain

2001-11-01T23:59:59.000Z

179

On the application of the MODTRAN4 atmospheric radiative transfer code to optical remote sensing  

Science Conference Proceedings (OSTI)

The quantification of atmospheric effects on the solar radiation measured by a spaceborne or airborne optical sensor is required for some key tasks in remote sensing, such as atmospheric correction, simulation of realistic scenarios or retrieval of atmospheric ...

Luis Guanter; Rudolf Richter; Hermann Kaufmann

2009-01-01T23:59:59.000Z

180

Four-Stream Spherical Harmonic Expansion Approximation for Solar Radiative Transfer  

Science Conference Proceedings (OSTI)

This paper presents a four-stream extension of the ?-Eddington approximation by considering the higher-order spherical harmonic expansion in radiative intensity. By using the orthogonality relation of the spherical harmonic functions, the ...

J. Li; V. Ramaswamy

1996-04-01T23:59:59.000Z

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.


181

Effect of Spatial Organization on Solar Radiative Transfer in Three-Dimensional Idealized Stratocumulus Cloud Fields  

Science Conference Proceedings (OSTI)

To relate the error associated with 1D radiative calculations to the geometrical scales of cloud organization and/or in-cloud optical inhomogeneities, a new idealized methodology, based on a Fourier statistical technique, has been developed. ...

F. Di Giuseppe; A. M. Tompkins

2003-08-01T23:59:59.000Z

182

On the use of flux limiters in the discrete ordinates method for 3D radiation calculations in absorbing and scattering media  

Science Conference Proceedings (OSTI)

The application of flux limiters to the discrete ordinates method (DOM), S"N, for radiative transfer calculations is discussed and analyzed for 3D enclosures for cases in which the intensities are strongly coupled to each other such as: radiative equilibrium ... Keywords: Discrete ordinates method (DOM), Flux limiters, Newton-Krylov GMRES, Non-homogeneous 3D media, Radiation heat transfer, Radiative transfer equation (RTE), TVD schemes

William F. Godoy; Paul E. DesJardin

2010-05-01T23:59:59.000Z

183

Sensitivity of cloud property retrievals to differences in radiative transfer simulations  

E-Print Network (OSTI)

RTMs for multiple scattering calculations: Monte Carlo, MODTRAN4v2r0 (beta release), DAK and SHDOM TRANsmittance and radiance code (MODTRAN), the multiple scattering calculations are based on the Discrete zenith angles to obtain N equations for N unknowns. These unknowns may be solved numerically. The MODTRAN

Stoffelen, Ad

184

Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout  

Science Conference Proceedings (OSTI)

This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

2010-12-15T23:59:59.000Z

185

3D Lya radiation transfer. II. Fitting the Lyman break galaxy MS 1512-cB58 and implications for Lya emission in high-z starbursts  

E-Print Network (OSTI)

Using our 3D Lya radiation transfer code, we compute the radiation transfer of Lya and UV continuum photons including dust. Observational constraints on the neutral gas (column density, kinematics, etc.) are taken from other analysis of this object. RESULTS: The observed Lya profile of MS 1512--cB58 is reproduced for the first time taking radiation transfer and all observational constraints into account. The observed absorption profile is found to result naturally from the observed amount of dust and the relatively high HI column density. Radiation transfer effects and suppresion by dust transform a strong intrinsic Lya emission with EW(Lya)>~ 60 Ang into the observed faint superposed Lya emission peak. We propose that the vast majority of LBGs have intrinsically EW(Lya)~60-80 Ang or larger, and that the main physical parameter responsible for the observed variety of Lya strengths and profiles in LBGs is N_H and the accompanying variation of the dust content. Observed EW(Lya) distributions, Lya luminosity functions, and related quantities must therefore be corrected for radiation transfer and dust effects. The implications from our scenario on the duty-cycle of Lya emitters are also discussed.

Daniel Schaerer; Anne Verhamme

2008-01-08T23:59:59.000Z

186

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

E-Print Network (OSTI)

Engineering Department, Cockrell School of Engineering, The University of Texas at Austin, 204 E. Dean Keeton Street, Austin, TX 78705, USA a r t i c l e i n f o Article history: Received 26 April 2011 Received a c t Solar radiation is the energy source driving the metabolic activity of microorganisms able

Pilon, Laurent

187

THE I3RC: Bringing Together the Most Advanced Radiative Transfer Tools for Cloudy Atmospheres  

Science Conference Proceedings (OSTI)

The interaction of clouds with solar and terrestrial radiation is one of the most important topics of climate research. In recent years it has been recognized that only a full three-dimensional (3D) treatment of this interaction can provide ...

Robert F. Cahalan; Lazaros Oreopoulos; Alexander Marshak; K. Franklin Evans; Anthony B. Davis; Robert Pincus; Ken H. Yetzer; Bernhard Mayer; Roger Davies; Thomas P. Ackerman; Howard W. Barker; Eugene E. Clothiaux; Robert G. Ellingson; Michael J. Garay; Evgueni Kassianov; Stefan Kinne; Andreas Macke; William O'Hirok; Philip T. Partain; Sergei M. Prigarin; Alexei N. Rublev; Graeme L. Stephens; Frederic Szczap; Ezra E. Takara; Támas Várnai; Guoyong Wen; Tatiana B. Zhuravleva

2005-09-01T23:59:59.000Z

188

Field Experiment for Measurement of the Radiative Characteristics of a Hazy Atmosphere  

Science Conference Proceedings (OSTI)

Theoretical two-and three-dimensional solutions to the radiative transfer equation have been applied to the earth-atmosphere system. A field experiment was conducted to test this theory. in the experiment the upward radiance was measured above ...

Y. J. Kaufman; T. W. Brakke; E. Eloranta

1986-06-01T23:59:59.000Z

189

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

SciTech Connect

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

190

Suppressing nonphysical overheating with a modified implicit Monte Carlo method for time-dependent radiative transfer  

SciTech Connect

In this note we develop a robust implicit Monte Carlo (IMC) algorithm based on more accurately updating the linearized equilibrium radiation energy density. The method does not introduce oscillations in the solution and has the same limit as {Delta}t{yields}{infinity} as the standard Fleck and Cummings IMC method. Moreover, the approach we introduce can be trivially added to current implementations of IMC by changing the definition of the Fleck factor. Using this new method we develop an adaptive scheme that uses either standard IMC or the modified method basing the adaptation on a zero-dimensional problem solved in each cell. Numerical results demonstrate that the new method alleviates both the nonphysical overheating that occurs in standard IMC when the time step is large and significantly diminishes the statistical noise in the solution.

Mcclarren, Ryan G [Los Alamos National Laboratory; Urbatsch, Todd J [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

191

Retrieval of Ice Cloud Properties from AIRS and MODIS Observations Based on a Fast High-Spectral-Resolution Radiative Transfer Model  

Science Conference Proceedings (OSTI)

A computationally efficient high-spectral-resolution cloudy-sky radiative transfer model (HRTM) in the thermal infrared region (700–1300 cm?1, 0.1 cm?1 spectral resolution) is advanced for simulating the upwelling radiance at the top of atmosphere ...

Chenxi Wang; Ping Yang; Steven Platnick; Andrew K. Heidinger; Bryan A. Baum; Thomas Greenwald; Zhibo Zhang; Robert E. Holz

2013-03-01T23:59:59.000Z

192

Convection Heat Transfer  

Science Conference Proceedings (OSTI)

...Heat-Transfer Equations, Fundamentals of Modeling for Metals Processing, Vol 22A, ASM Handbook, ASM International, 2009, p 625â??658...

193

Asymptotic diffusion limit of the symbolic Monte-Carlo method for the transport equation  

Science Conference Proceedings (OSTI)

We use asymptotic analysis to study the diffusion limit of the Symbolic Implicit Monte-Carlo (SIMC) method for the transport equation. For standard SIMC with piecewise constant basis functions, we demonstrate mathematically that the solution converges ... Keywords: Monte-Carlo method, radiative transfer

J.-F. Clouët; G. Samba

2004-03-01T23:59:59.000Z

194

Homogenization of a spectral equation with drift in linear Guillaume Bal  

E-Print Network (OSTI)

theory posed in a periodic heterogeneous domain. This equation models the stability of nuclear reactor Introduction The power distribution in a nuclear reactor is determined by solving a linear transport spectral in radiative transfer theory, which models the propagation of acoustic, electromagnetic, or elastic waves

Bal, Guillaume

195

Radiators  

SciTech Connect

A heat-exchange radiator is connected to a fluid flow circuit by a connector which provides one member of an interengageable spigot and socket pair for push-fit, fluid-tight, engagement between the connector and the radiator, with latching formations at least one of which is resilient. Preferably the connector carries the spigot which tapers and engages with a socket of corresponding shape, the spigot carrying an O-ring seal and either latching fingers or a resilient latching circlip.

Webster, D. M.

1985-07-30T23:59:59.000Z

196

Atmospheric Longwave Irradiance Uncertainty: Pyrgeometers Compared to an Absolute Sky-Scanning Radiometer, Atmospheric Emitted Radiance Interferometer, and Radiative Transfer Model Calculations  

SciTech Connect

Because atmospheric longwave radiation is one of the most fundamental elements of an expected climate change, there has been a strong interest in improving measurements and model calculations in recent years. Important questions are how reliable and consistent are atmospheric longwave radiation measurements and calculations and what are the uncertainties? The First International Pyrgeometer and Absolute Sky-scanning Radiometer Comparison, which was held at the Atmospheric Radiation Measurement program's Souther Great Plains site in Oklahoma, answers these questions at least for midlatitude summer conditions and reflects the state of the art for atmospheric longwave radiation measurements and calculations. The 15 participating pyrgeometers were all calibration-traced standard instruments chosen from a broad international community. Two new chopped pyrgeometers also took part in the comparison. And absolute sky-scanning radiometer (ASR), which includes a pyroelectric detector and a reference blackbody source, was used for the first time as a reference standard instrument to field calibrate pyrgeometers during clear-sky nighttime measurements. Owner-provided and uniformly determined blackbody calibration factors were compared. Remarkable improvements and higher pyrgeometer precision were achieved with field calibration factors. Results of nighttime and daytime pyrgeometer precision and absolute uncertainty are presented for eight consecutive days of measurements, during which period downward longwave irradiance varied between 260 and 420 W m-2. Comparisons between pyrgeometers and the absolute ASR, the atmospheric emitted radiance interferometer, and radiative transfer models LBLRTM and MODTRAN show a surprisingly good agreement of <2 W m-2 for nighttime atmospheric longwave irradiance measurements and calculations.

Philipona, J. R.; Dutton, Ellsworth G.; Stoffel, T.; Michalsky, Joseph J.; Reda, I.; Stifter, Armin; Wendling, Peter; Wood, Norm; Clough, Shepard A.; Mlawer, Eli J.; Anderson, Gail; Revercomb, Henry E.; Shippert, Timothy R.

2001-06-04T23:59:59.000Z

197

The Effect of Realistic Radiative Transfer on Potential Vorticity Structures, Including the Influence of Background Shear and Strain  

Science Conference Proceedings (OSTI)

A modified version of the radiation scheme of Shine is used to investigate the decay of small-scale potential vorticity structures characteristic of those observed in the lower and middle stratosphere. Following Fels, effective thermal damping ...

P. H. Haynes; W. E. Ward

1993-10-01T23:59:59.000Z

198

Development of a second-generation regional climate model (RegCM2). Part I: Boundary-layer and radiative transfer processes  

SciTech Connect

During the last few years the development of a second-generation regional climate modeling system (RegCM2) has been completed at the National Center for Atmospheric Research (NCAR). Based upon the National Center for Atmospheric Research-Pennsylvania State University Mesoscale Model (MM4), RegCM2 includes improved formulations of boundary layer, radiative transfer, surface physics, cumulus convection, and time integration technique, which make it more physically comprehensive and more computationally efficient than the previous regional climate model version. This paper discusses a number of month-long simulations over the European region that were conducted to test the new RegCM2 boundary-layer parameterization (the scheme developed by Holtsag et al.) and radiative transfer formulation [the package developed for the NCAR Community Climate Model 2 (CCM2)]. Both schemes significantly affect the model precipitation, temperature, moisture, and cloudiness climatology, leading to overall more realistic results, while they do not substantially modify the model performance in simulating the aggregated characteristics of synoptic patterns. Description of the convective processes and procedures of boundary condition assimilation included in RegCM2 is presented in companion paper by Giorgi et al. 26 refs., 11 figs., 10 tabs.

Giorgi, F.; Marinucci, M.R.; Bates, G.T. (National Center for Atmospheric Research, Boulder, CO (United States))

1993-10-01T23:59:59.000Z

199

Fast 2D non-LTE radiative modelling of prominences I. Numerical methods and benchmark results  

E-Print Network (OSTI)

New high-resolution spectropolarimetric observations of solar prominences require improved radiative modelling capabilities in order to take into account both multi-dimensional - at least 2D - geometry and complex atomic models. This makes necessary the use of very fast numerical schemes for the resolution of 2D non-LTE radiative transfer problems considering freestanding and illuminated slabs. The implementation of Gauss-Seidel and successive over-relaxation iterative schemes in 2D, together with a multi-grid algorithm, is thoroughly described in the frame of the short characteristics method for the computation of the formal solution of the radiative transfer equation in cartesian geometry. We propose a new test for multidimensional radiative transfer codes and we also provide original benchmark results for simple 2D multilevel atom cases which should be helpful for the further development of such radiative transfer codes, in general.

L. Leger; L. Chevallier; F. Paletou

2007-03-27T23:59:59.000Z

200

A fourth-order symplectic finite-difference time-domain (FDTD) method for light scattering and a 3D Monte Carlo code for radiative transfer in scattering systems  

E-Print Network (OSTI)

When the finite-difference time-domain (FDTD) method is applied to light scattering computations, the far fields can be obtained by either a volume integration method, or a surface integration method. In the first study, we investigate the errors associated with the two near-to-far field transform methods. For a scatterer with a small refractive index, the surface approach is more accurate than its volume counterpart for computing the phase functions and extinction efficiencies; however, the volume integral approach is more accurate for computing other scattering matrix elements. If a large refractive index is involved, the results computed from the volume integration method become less accurate, whereas the surface method still retains the same order of accuracy as in the situation of a small refractive index. In my second study, a fourth order symplectic FDTD method is applied to the problem of light scattering by small particles. The total-field/ scattered-field (TF/SF) technique is generalized for providing the incident wave source conditions in the symplectic FDTD (SFDTD) scheme. Numerical examples demonstrate that the fourthorder symplectic FDTD scheme substantially improves the precision of the near field calculation. The major shortcoming of the fourth-order SFDTD scheme is that it requires more computer CPU time than the conventional second-order FDTD scheme if the same grid size is used. My third study is on multiple scattering theory. We develop a 3D Monte Carlo code for the solving vector radiative transfer equation, which is the equation governing the radiation field in a multiple scattering medium. The impulse-response relation for a plane-parallel scattering medium is studied using our 3D Monte Carlo code. For a collimated light beam source, the angular radiance distribution has a dark region as the detector moves away from the incident point. The dark region is gradually filled as multiple scattering increases. We have also studied the effects of the finite size of clouds. Extending the finite size of clouds to infinite layers leads to underestimating the reflected radiance in the multiple scattering region, especially for scattering angles around 90 degrees. The results have important applications in the field of remote sensing.

Zhai, Pengwang

2006-08-01T23:59:59.000Z

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.


201

The Quasi-stationary Structure of Radiating Shock Waves; 1, The One-temperature Fluid  

E-Print Network (OSTI)

We calculate the quasi-stationary structure of a radiating shock wave propagating through a spherically symmetric shell of cold gas by solving the time-dependent equations of radiation hydrodynamics on an adaptive grid. We show that this code successfully resolves the shock wave in both the subcritical and supercritical cases and, for the first time, we have reproduced all the expected features -- including the optically thin temperature spike at a supercritical shock front -- without invoking analytic jump conditions at the discontinuity. We solve the full moment equations for the radiation flux and energy density, but the shock wave structure can also be reproduced if the radiation flux is assumed to be proportional to the gradient of the energy density (the diffusion approximation), as long as the radiation energy density is determined by the appropriate radiative transfer moment equation. We find that Zel'dovich and Raizer's analytic solution for the shock wave structure accurately describes a subcritical...

Sincell, M W; Mihalas, D L

1997-01-01T23:59:59.000Z

202

Handbook of heat transfer fundamentals  

SciTech Connect

This handbook is on the fundamentals of heat transfer. It provides coverage on conduction, convection, and radiation and on thermophysical properties of materials.

Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

1985-01-01T23:59:59.000Z

203

Partnering Today: Technology Transfer Highlights  

THE LLNL TECHNOLOGY COMPANY PRODUCTS Partnering Today: Technology Transfer Highlights 10 Ametek-Ortec: High-precision Radiation Detectors ORTEC, a unit of AMETEK, is ...

204

Heat and moisture transfer through clothing  

E-Print Network (OSTI)

R. C. Eberhart (ed), Heat transfer in medicine and biology.Convective and radiative heat transfer coefficients for2008. Study of heat and moisture transfer within multi-layer

Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie

2009-01-01T23:59:59.000Z

205

A General Strategy for Physics-Based Model Validation Illustrated with Earthquake Phenomenology, Atmospheric Radiative Transfer, and Computational Fluid Dynamics  

E-Print Network (OSTI)

Validation is often defined as the process of determining the degree to which a model is an accurate representation of the real world from the perspective of its intended uses. Validation is crucial as industries and governments depend increasingly on predictions by computer models to justify their decisions. In this article, we survey the model validation literature and propose to formulate validation as an iterative construction process that mimics the process occurring implicitly in the minds of scientists. We thus offer a formal representation of the progressive build-up of trust in the model, and thereby replace incapacitating claims on the impossibility of validating a given model by an adaptive process of constructive approximation. This approach is better adapted to the fuzzy, coarse-grained nature of validation. Our procedure factors in the degree of redundancy versus novelty of the experiments used for validation as well as the degree to which the model predicts the observations. We illustrate the new methodology first with the maturation of Quantum Mechanics as the arguably best established physics theory and then with several concrete examples drawn from some of our primary scientific interests: a cellular automaton model for earthquakes, an anomalous diffusion model for solar radiation transport in the cloudy atmosphere, and a computational fluid dynamics code for the Richtmyer-Meshkov instability. This article is an augmented version of Sornette et al. [2007] that appeared in Proceedings of the National Academy of Sciences in 2007 (doi: 10.1073/pnas.0611677104), with an electronic supplement at URL http://www.pnas.org/cgi/content/full/0611677104/DC1. Sornette et al. [2007] is also available in preprint form at physics/0511219.

Didier Sornette; Anthony B. Davis; James R. Kamm; Kayo Ide

2007-10-01T23:59:59.000Z

206

Hybrid Radiator-Cooling System  

Technology Development & Commercialization Current Challenges Coolant radiators in highway trucks are designed to transfer maximum heat at a ...

207

Penetration equations  

Science Conference Proceedings (OSTI)

In 1967, Sandia National Laboratories published empirical equations to predict penetration into natural earth materials and concrete. Since that time there have been several small changes to the basic equations, and several more additions to the overall technique for predicting penetration into soil, rock, concrete, ice, and frozen soil. The most recent update to the equations was published in 1988, and since that time there have been changes in the equations to better match the expanding data base, especially in concrete penetration. This is a standalone report documenting the latest version of the Young/Sandia penetration equations and related analytical techniques to predict penetration into natural earth materials and concrete. 11 refs., 6 tabs.

Young, C.W. [Applied Research Associates, Inc., Albuquerque, NM (United States)

1997-10-01T23:59:59.000Z

208

Modeling radiation characteristics of semitransparent media containing bubbles or particles.  

E-Print Network (OSTI)

and heat, mass, and radiation transfer,” Journal of Non-Sacadura, J. F. , “Thermal radiation properties of dispersedG. , and Viskanta, R. , “Radiation characteristics of glass

Randrianalisoa, Jaona; Baillis, Dominique; Pilon, Laurent

2006-01-01T23:59:59.000Z

209

Approximations for radiative cooling and heating in the solar chromosphere  

E-Print Network (OSTI)

Context. The radiative energy balance in the solar chromosphere is dominated by strong spectral lines that are formed out of LTE. It is computationally prohibitive to solve the full equations of radiative transfer and statistical equilibrium in 3D time dependent MHD simulations. Aims. To find simple recipes to compute the radiative energy balance in the dominant lines under solar chromospheric conditions. Methods. We use detailed calculations in time-dependent and 2D MHD snapshots to derive empirical formulae for the radiative cooling and heating. Results. The radiative cooling in neutral hydrogen lines and the Lyman continuum, the H and K and intrared triplet lines of singly ionized calcium and the h and k lines of singly ionized magnesium can be written as a product of an optically thin emission (dependent on temperature), an escape probability (dependent on column mass) and an ionization fraction (dependent on temperature). In the cool pockets of the chromosphere the same transitions contribute to the heat...

Carlsson, Mats

2012-01-01T23:59:59.000Z

210

Dispersed-Flow Film Boiling Heat Transfer Data near Spacer Grids in a Rod Bundle  

Science Conference Proceedings (OSTI)

Technical Paper / Radiation Effects and Their Relationship to Geological Repository / Heat Transfer and Fluid Flow

Graydon L. Yoder; Jr.; David G. Morris; Charles B. Mullins; Larry J. Ott

211

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, André

2007-01-01T23:59:59.000Z

212

Tech Transfer  

Tech Transfer The Industrial Partnerships Office is improving tech transfer processes with our very own Yellow Belt. Several of the Lab's process ...

213

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

resolved Radiative Transfer Model: MODTRAN……….131 APMEXModerate Imaging Spectroradiometer MODTRAN MODerate spectralprovide by MODTRAN…………………………………………………………………………133 Table 4.2

Zhu, Aihua

2010-01-01T23:59:59.000Z

214

The 27–28 October 1986 FIRF IFO Cirrus Case Study: Comparison of Radiative Transfer Theory with Observations by Satellite and Aircraft  

Science Conference Proceedings (OSTI)

Observations of cirrus and altocumulus clouds during the First International Satellite Cloud Climatology Project Regional Experiment (FIRE) are compared to theoretical models of cloud radiative properties. Three tests are performed. First, ...

Bruce A. Wielicki; J.T. Suttles; Andrew J. Heymsfield; Ronald M. Welch; James D. Spinhirne; Man-Li C. Wu; David O'C. Starr; Lindsay Parker; Robert F. Arduini

1990-11-01T23:59:59.000Z

215

An Ultralight Aircraft as Platform for Research in the Lower Troposphere: System Performance and First Results from Radiation Transfer Studies in Stratiform Aerosol Layers and Broken Cloud Conditions  

Science Conference Proceedings (OSTI)

The ultraviolet actinic radiation flux governing the photochemical reactions in the atmosphere is dependent on the optical properties of atmospheric aerosols and reflective surfaces of ground and clouds. Theoretical models exist for horizontal ...

Wolfgang Junkermann

2001-06-01T23:59:59.000Z

216

Transferring Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Transferring Data Transferring Data to and from NERSC Yushu Yao 1 Tuesday, March 8, 2011 Overview 2 * Structure of NERSC Systems and Disks * Data Transfer Nodes * Transfer Data from/to NERSC - scp/sftp - bbcp - GridFTP * Sharing Data Within NERSC Tuesday, March 8, 2011 Systems and Disks 3 System Hopper Franklin Carver Euclid Data Transfer Node PDSF Global Home ($HOME) Global Scratch ($GSCRATCH) Project Directory Local Non-shared Scratch Data transfer nodes can access most of the disks, suggested for transferring data in/out NERSC Tuesday, March 8, 2011 Data Transfer Nodes * Two Servers Available Now: - dtn01.nersc.gov and dtn02.nersc.gov - Accessible by all NERSC users * Designed to Transfer Data: - High speed connection to HPSS and NGF (Global Home, Project, and Global Scratch) - High speed ethernet to wide area network

217

Network simulation solutions for laminar radiating dissipative magneto-gas dynamic heat transfer over a wedge in non-Darcian porous regime  

Science Conference Proceedings (OSTI)

We study the steady-state, magnetohydrodynamic, optically thick, dissipative gas boundary layer flow and heat transfer past a non-isothermal porous wedge embedded in a scattering, homogenous, isotropic Darcy-Forchheimer porous medium, with significant ... Keywords: Boundary layers, Hartmann number, Joule heating, Magneto-gas dynamics, Network simulation

JoaquíN Zueco; O. Anwar BéG

2009-08-01T23:59:59.000Z

218

Splitting schemes for hyperbolic heat conduction equation  

E-Print Network (OSTI)

Rapid processes of heat transfer are not described by the standard heat conduction equation. To take into account a finite velocity of heat transfer, we use the hyperbolic model of heat conduction, which is connected with the relaxation of heat fluxes. In this case, the mathematical model is based on a hyperbolic equation of second order or a system of equations for the temperature and heat fluxes. In this paper we construct for the hyperbolic heat conduction equation the additive schemes of splitting with respect to directions. Unconditional stability of locally one-dimensional splitting schemes is established. New splitting schemes are proposed and studied for a system of equations written in terms of the temperature and heat fluxes.

Vabishchevich, Petr N

2010-01-01T23:59:59.000Z

219

Technology Transfer  

A new search feature has been implemented, which allows searching of technology transfer information across the Department of Energy Laboratories.

220

Spectral Reflectance and Atmospheric Energetics in Cirrus-like Clouds. Part II: Applications of a Fourier-Riccati Approach to Radiative Transfer  

Science Conference Proceedings (OSTI)

One of the major sources of uncertainty in climate studies is the detection of cirrus clouds and characterization of their radiative properties. Combinations of water vapor absorption channels (e.g., 1.38 µm), ice-water absorption channels (e.g., ...

Si-Chee Tsay; Philip M. Gabriel; Michael D. King; Graeme L. Stephens

1996-12-01T23:59:59.000Z

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.


221

CRASH: A BLOCK-ADAPTIVE-MESH CODE FOR RADIATIVE SHOCK HYDRODYNAMICS-IMPLEMENTATION AND VERIFICATION  

SciTech Connect

We describe the Center for Radiative Shock Hydrodynamics (CRASH) code, a block-adaptive-mesh code for multi-material radiation hydrodynamics. The implementation solves the radiation diffusion model with a gray or multi-group method and uses a flux-limited diffusion approximation to recover the free-streaming limit. Electrons and ions are allowed to have different temperatures and we include flux-limited electron heat conduction. The radiation hydrodynamic equations are solved in the Eulerian frame by means of a conservative finite-volume discretization in either one-, two-, or three-dimensional slab geometry or in two-dimensional cylindrical symmetry. An operator-split method is used to solve these equations in three substeps: (1) an explicit step of a shock-capturing hydrodynamic solver; (2) a linear advection of the radiation in frequency-logarithm space; and (3) an implicit solution of the stiff radiation diffusion, heat conduction, and energy exchange. We present a suite of verification test problems to demonstrate the accuracy and performance of the algorithms. The applications are for astrophysics and laboratory astrophysics. The CRASH code is an extension of the Block-Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US) code with a new radiation transfer and heat conduction library and equation-of-state and multi-group opacity solvers. Both CRASH and BATS-R-US are part of the publicly available Space Weather Modeling Framework.

Van der Holst, B.; Toth, G.; Sokolov, I. V.; Myra, E. S.; Fryxell, B.; Drake, R. P. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Powell, K. G. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Holloway, J. P. [Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Stout, Q. [Computer Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Adams, M. L.; Morel, J. E. [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Karni, S. [Department of Mathematics, University of Michigan, Ann Arbor, MI 48109 (United States)

2011-06-01T23:59:59.000Z

222

Satellite-based remote sensing of cirrus clouds: hyperspectral radiative transfer modeling, analysis of uncertainties in in-situ cloud extinction measurements and intercomparison of cirrus retrievals from a-train instruments  

E-Print Network (OSTI)

This dissertation consists of three parts, each devoted to a particular issue of significant importance for satellite-based remote sensing of cirrus clouds. In the first part, we develop and present a fast infrared radiative transfer model on the basis of the adding-doubling principle. The model aims to facilitate the radiative transfer computations involved in hyperspectral remote sensing applications. The model is applicable to a variety of cloud conditions, including vertically inhomogeneous or multilayered clouds. It is shown that for hyperspectral applications the model is two order-of-magnitude faster than the well-known discrete ordinate transfer (DISORT) model, while maintains a similar accuracy. The second part is devoted to the investigation of uncertainties in the FSSP (Forward Scattering Spectrometer Probe) measurement of cloud extinction by small ice particles. First, the single-scattering properties of small ice particles in cirrus clouds are derived and compared to those of equivalent spheres according to various definitions. It is found that, although small ice particles in cirrus clouds are often “quasi-spherical”, their scattering phase functions and asymmetry factors are significant different from those of ice spheres. Such differences may lead to substantial underestimation of cloud extinction in FSSP measurement, if small ice particles are assumed to be spheres. In the third part, we present a comparison of cirrus cloud optical thickness retrievals from two important instruments, MODIS (Moderate Resolution Imaging Spectrometer) and POLDER (Polarization and Directionality of Earth’s Reflection), on board NASA’s A-train satellite constellation. The comparison reveals a large difference. Several possible reasons are discussed. It is found that much of the difference is attributable to the difference between the MODIS and POLDER retrieval algorithm in the assumption of cirrus cloud bulk scattering properties. Potential implications of the difference for climate studies are investigated. An important finding is that the use of an unrealistic cirrus bulk scattering model might introduce artificial seasonal variation of cirrus optical thickness and shortwave radiative forcing into the retrieval.

Zhang, Zhibo

2008-08-01T23:59:59.000Z

223

Radiation Hydrodynamics  

DOE Green Energy (OSTI)

The discipline of radiation hydrodynamics is the branch of hydrodynamics in which the moving fluid absorbs and emits electromagnetic radiation, and in so doing modifies its dynamical behavior. That is, the net gain or loss of energy by parcels of the fluid material through absorption or emission of radiation are sufficient to change the pressure of the material, and therefore change its motion; alternatively, the net momentum exchange between radiation and matter may alter the motion of the matter directly. Ignoring the radiation contributions to energy and momentum will give a wrong prediction of the hydrodynamic motion when the correct description is radiation hydrodynamics. Of course, there are circumstances when a large quantity of radiation is present, yet can be ignored without causing the model to be in error. This happens when radiation from an exterior source streams through the problem, but the latter is so transparent that the energy and momentum coupling is negligible. Everything we say about radiation hydrodynamics applies equally well to neutrinos and photons (apart from the Einstein relations, specific to bosons), but in almost every area of astrophysics neutrino hydrodynamics is ignored, simply because the systems are exceedingly transparent to neutrinos, even though the energy flux in neutrinos may be substantial. Another place where we can do ''radiation hydrodynamics'' without using any sophisticated theory is deep within stars or other bodies, where the material is so opaque to the radiation that the mean free path of photons is entirely negligible compared with the size of the system, the distance over which any fluid quantity varies, and so on. In this case we can suppose that the radiation is in equilibrium with the matter locally, and its energy, pressure and momentum can be lumped in with those of the rest of the fluid. That is, it is no more necessary to distinguish photons from atoms, nuclei and electrons, than it is to distinguish hydrogen atoms from helium atoms, for instance. There are all just components of a mixed fluid in this case. So why do we have a special subject called ''radiation hydrodynamics'', when photons are just one of the many kinds of particles that comprise our fluid? The reason is that photons couple rather weakly to the atoms, ions and electrons, much more weakly than those particles couple with each other. Nor is the matter-radiation coupling negligible in many problems, since the star or nebula may be millions of mean free paths in extent. Radiation hydrodynamics exists as a discipline to treat those problems for which the energy and momentum coupling terms between matter and radiation are important, and for which, since the photon mean free path is neither extremely large nor extremely small compared with the size of the system, the radiation field is not very easy to calculate. In the theoretical development of this subject, many of the relations are presented in a form that is described as approximate, and perhaps accurate only to order of {nu}/c. This makes the discussion cumbersome. Why are we required to do this? It is because we are using Newtonian mechanics to treat our fluid, yet its photon component is intrinsically relativistic; the particles travel at the speed of light. There is a perfectly consistent relativistic kinetic theory, and a corresponding relativistic theory of fluid mechanics, which is perfectly suited to describing the photon gas. But it is cumbersome to use this for the fluid in general, and we prefer to avoid it for cases in which the flow velocity satisfies {nu} << c. The price we pay is to spend extra effort making sure that the source-sink terms relating to our relativistic gas component are included in the equations of motion in a form that preserves overall conservation of energy and momentum, something that would be automatic if the relativistic equations were used throughout.

Castor, J I

2003-10-16T23:59:59.000Z

224

An Earth Outgoing Longwave Radiation Climate Model. Part II: Radiation with Clouds Included  

Science Conference Proceedings (OSTI)

An Earth outgoing longwave radiation (OLWR) climate model was constructed for radiation budget studies. The model consists of the upward radiative transfer parameterization of Thompson and Warren, the cloud cover model of Sherr et al., and a ...

Shi-Keng Yang; G. Louis Smith; Fred L. Bartman

1988-10-01T23:59:59.000Z

225

A Two-Dimensional Radiation-Turbulence Climate Model. I: Sensitivity to Cirrus Radiative Properties  

Science Conference Proceedings (OSTI)

Based on the thermodynamic energy balance between radiation and vertical plus horizontal dynamic transports, a two-dimensional radiation-turbulence climate model is developed. This model consists of a broadband solar and IR radiation transfer ...

Szu-Cheng S. Ou; Kuo-Nan Liou

1984-08-01T23:59:59.000Z

226

The Quasi-stationary Structure of Radiating Shock Waves; 2, The Two-temperature Fluid  

E-Print Network (OSTI)

We solve the equations of radiation hydrodynamics in the two-temperature fluid approximation on an adaptive grid. The temperature structure depends upon the electron-ion energy exchange length, $l_{ei}$, and the electron conduction length, $l_{ec}$. Three types of radiating shock structure are observed: subcritical, where preheating of the unshocked gas is negligible; electron supercritical, where radiation preheating raises the temperature of the unshocked electron fluid to be equal to the final electron temperature; supercritical, where preheating and electron-ion energy exchange raise the preshock $T_{e,i}$ to their final post shock values. No supercritical shock develops when $l_{ei}$ is larger than the photospheric depth of the shocked gas because a negligible amount of the ion energy is transferred to the electrons and the shock is weakly radiating. Electron conduction smooths the $T_e$ profile on a length scale $l_{ec}$, reducing the radiation flux.

Sincell, M W; Mihalas, D L

1997-01-01T23:59:59.000Z

227

Enhanced heat transfer for thermionic power modules  

DOE Green Energy (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

228

HYDRA-II: A hydrothermal analysis computer code: Volume 1, Equations and numerics  

Science Conference Proceedings (OSTI)

HYDRA-II is a hydrothermal computer code capable of three-dimensional analysis of coupled conduction, convection, and thermal radiation problems. This code is especially appropriate for simulating the steady-state performance of spent fuel storage systems. The code has been evaluated for this application for the US Department of Energy's Commercial Spent Fuel Management Program. HYDRA-II provides a finite difference solution in Cartesian coordinates to the equations governing the conservation of mass, momentum, and energy. A cylindrical coordinate system may also be used to enclose the Cartesian coordinate system. This exterior coordinate system is useful for modeling cylindrical cask bodies. The difference equations for conservation of momentum are enhanced by the incorporation of directional porosities and permeabilities that aid in modeling solid structures whose dimensions may be smaller than the computational mesh. The equation for conservation of energy permits of modeling of orthotropic physical properties and film resistances. Several automated procedures are available to model radiation transfer within enclosures and from fuel rod to fuel rod. The documentation of HYDRA-II is presented in three separate volumes. This volume, Volume I - Equations and Numerics, describes the basic differential equations, illustrates how the difference equations are formulated, and gives the solution procedures employed. Volume II - User's Manual contains code flow charts, discusses the code structure, provides detailed instructions for preparing an input file, and illustrates the operation of the code by means of a model problem. The final volume, Volume III - Verification/Validation Assessments, presents results of numerical simulations of single- and multiassembly storage systems and comparisons with experimental data. 4 refs.

McCann, R.A.

1987-04-01T23:59:59.000Z

229

A Reduced Radiation Grid for the ECMWF Integrated Forecasting System  

Science Conference Proceedings (OSTI)

A specific interface between the radiation transfer calculations and the rest of the ECMWF model was introduced in 2003, potentially providing substantial economy in computer time by reducing the spatial resolution at which radiation transfer is ...

Jean-Jacques Morcrette; George Mozdzynski; Martin Leutbecher

2008-12-01T23:59:59.000Z

230

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

Science Conference Proceedings (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 night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. Most PCMs do not conduct heat very well. Using an innovative, electroless encapsulation technique, USF is enhancing the heat transfer capability of its PCMs. The inner walls of the capsules will be lined with a corrosion-resistant, high-infrared emissivity coating, and the absorptivity of the PCM will be controlled with the addition of nano-sized particles. USF’s PCMs remain stable at temperatures from 600 to 1,000°C and can be used for solar thermal power storage, nuclear thermal power storage, and other applications.

None

2011-12-05T23:59:59.000Z

231

Does an accelerated electron radiate Unruh radiation?  

E-Print Network (OSTI)

An accelerated particle sees the Minkowski vacuum as thermally excited, and the particle moves stochastically due to an interaction with the thermal bath. This interaction fluctuates the particle's transverse momenta like the Brownian motion in a heat bath. Because of this fluctuating motion, it has been discussed that the accelerated charged particle emits extra radiation (the Unruh radiation) in addition to the classical Larmor radiation, and experiments are under planning to detect such radiation by using ultrahigh intensity lasers constructed in near future. There are, however, counterarguments that the radiation is canceled by an interference effect between the vacuum fluctuation and the fluctuating motion. In fact, in the case of an internal detector where the Heisenberg equation of motion can be solved exactly, there is no additional radiation after the thermalization is completed. In this paper, we revisit the issue in the case of an accelerated charged particle in the scalar QED. We first prove the e...

Iso, Satoshi; Zhang, Sen

2010-01-01T23:59:59.000Z

232

NREL Improves Window Heat Transfer Calculations (Fact Sheet)...  

NLE Websites -- All DOE Office Websites (Extended Search)

and interior radiation. The most significant errors were found in detailed window heat transfer algorithms due to implementation problems. The results show a decrease in...

233

Measure of Diffusion Model Error for Thermal Radiation Transport  

E-Print Network (OSTI)

The diffusion approximation to the equation of transfer (Boltzmann transport equation) is usually applied to media where scattering dominates the interactions. Diffusion approximation helps in significant savings in terms of code complexity and computational time. However, this approximation often has significant error. Error due to the inherent nature of a physics model is called model error. Information about the model error associated with the diffusion approximation is clearly desirable. An indirect measure of model error is a quantity that is related in some way to the error but not equal to the error. In general, indirect measures of error are expected to be less costly than direct measures. Perhaps the most well-known indirect measure of the diffusion model error is the variable-Eddington tensor. This tensor provides a great deal of information about the angular dependence of the angular intensity solution, but it is not always simple to interpret. We define a new indirect measure of the diffusion model error called the diffusion model error source (DME source). When this DME source is added to the diffusion equation, the transport solution for the angular-integrated intensity is obtained. In contrast to the variable-Eddington tensor, our DME source is a scalar that is conceptually easy to interpret. In addition to defining the DME source analytically, we show how to generate this source numerically relative to the Sn radiative transfer equations with linear-discontinuous spatial discretization. This numerical source is computationally tested and shown to reproduce the Sn solution for a number of problems. Our radiative transfer model solves a coupled, time dependent, multi-frequency, 1-D slab equation and material heat transfer equation. We then use diffusion approximation to solve the same problem. The difference due to this approximation can be modelled by a “diffusion source”. The diffusion source is defined as an amount of inhomogeneous source that, when added to a diffusion calculation, gives a solution for the angle-integrated intensity that is equal to the transport solution.

Kumar, Akansha

2013-05-01T23:59:59.000Z

234

Modeling of Heat Transfer in Rooms in the Modelica Buildings Library  

E-Print Network (OSTI)

for convective and radiative heat transfer yielded a twofoldModeling of Heat Transfer in Rooms in the Modelica “of California. MODELING OF HEAT TRANSFER IN ROOMS IN THE

Wetter, Michael

2013-01-01T23:59:59.000Z

235

EFFECT OF DUST ON Ly{alpha} PHOTON TRANSFER IN AN OPTICALLY THICK HALO  

SciTech Connect

We investigate the effects of dust on Ly{alpha} photons emergent from an optically thick medium by solving the integro-differential equation of radiative transfer of resonant photons. To solve the differential equations numerically, we use the weighted essentially non-oscillatory method. Although the effects of dust on radiative transfer are well known, the resonant scattering of Ly{alpha} photons makes the problem non-trivial. For instance, if the medium has an optical depth of dust absorption and scattering of {tau}{sub a} >> 1, {tau} >> 1, and {tau} >> {tau}{sub a}, the effective absorption optical depth in a random walk scenario would be equal to {radical}({tau}{sub a}({tau}{sub a}+{tau})). We show, however, that for a resonant scattering at frequency {nu}{sub 0}, the effective absorption optical depth would be even larger than {tau}({nu}{sub 0}). If the cross section of dust scattering and absorption is frequency-independent, the double-peaked structure of the frequency profile given by the resonant scattering is basically dust-independent. That is, dust causes neither narrowing nor widening of the width of the double-peaked profile. One more result is that the timescales of the Ly{alpha} photon transfer in an optically thick halo are also basically independent of the dust scattering, even when the scattering is anisotropic. This is because those timescales are mainly determined by the transfer in the frequency space, while dust scattering, either isotropic or anisotropic, does not affect the behavior of the transfer in the frequency space when the cross section of scattering is wavelength-independent. This result does not support the speculation that dust will lead to the smoothing of the brightness distribution of a Ly{alpha} photon source with an optically thick halo.

Yang Yang; Shu Chiwang [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Roy, Ishani [Computing Laboratory, University of Oxford, Oxford, OX1 3QD (United Kingdom); Fang Lizhi [Department of Physics, University of Arizona, Tucson, AZ 85721 (United States)

2011-10-01T23:59:59.000Z

236

Problem-orientable numerical algorithm for modelling multi-dimensional radiative MHD flows in astrophysics -- the hierarchical solution scenario  

E-Print Network (OSTI)

We present a hierarchical approach for enhancing the robustness of numerical solvers for modelling radiative MHD flows in multi-dimensions. This approach is based on clustering the entries of the global Jacobian in a hierarchical manner that enables employing a variety of solution procedures ranging from a purely explicit time-stepping up to fully implicit schemes. A gradual coupling of the radiative MHD equation with the radiative transfer equation in higher dimensions is possible. Using this approach, it is possible to follow the evolution of strongly time-dependent flows with low/high accuracies and with efficiency comparable to explicit methods, as well as searching quasi-stationary solutions for highly viscous flows. In particular, it is shown that the hierarchical approach is capable of modelling the formation of jets in active galactic nuclei and reproduce the corresponding spectral energy distribution with a reasonable accuracy.

A. A. Hujeirat

2004-10-26T23:59:59.000Z

237

Vibrational energy transfer in a diesel engine  

Science Conference Proceedings (OSTI)

The paths of vibrational energy transfer in a diesel engine were investigated in order to obtain insight into ways of reducing this transfer to the exterior surfaces and thereby reduce the radiated noise. The engine was tested in a nonrunning condition with simulated internal forces in order to study the different transfer paths separately. Vibration response measurements were made of individual engine components and lumped?parameter models were developed to simulate this response. These models were then used to determine component design changes that would reduce the energy transfer. Two design changes were implemented in the engine and a reduction of the energy transfer was achieved as predicted.

R. G. DeJong; R. H. Lyon

1977-01-01T23:59:59.000Z

238

Radiation Sources and Radioactive Materials (Connecticut)  

Energy.gov (U.S. Department of Energy (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...

239

Low Dose Radiation Research Program: Characterizing Bystander...  

NLE Websites -- All DOE Office Websites (Extended Search)

To order to investigate these variables for low-linear transfer (LET) radiation, an electron microbeam irradiation system has been developed. An electron source provides a beam...

240

Radiative Effects of Cloud-Type Variations  

Science Conference Proceedings (OSTI)

Radiative flux changes induced by the occurrence of different cloud types are investigated using International Satellite Cloud Climatology Project cloud data and a refined radiative transfer model from National Aeronautics and Space ...

Ting Chen; William B. Rossow; Yuanchong Zhang

2000-01-01T23:59:59.000Z

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.


241

Surface Radiation in the Tropical Pacific  

Science Conference Proceedings (OSTI)

Monthly surface radiative fluxes in the tropical Pacific between January 1970 and February 1978 have been calculated using a radiative transfer package which includes detailed treatments of the molecular and droplet absorptions and of the surface ...

Ming-Dah Chou

1985-01-01T23:59:59.000Z

242

Heat Transfer in Complex Fluids  

SciTech Connect

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

243

Technology Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Efficiency & Renewable and Energy - Commercialization Energy Efficiency & Renewable and Energy - Commercialization Deployment SBIR/STTR - Small Business Innovation Research and Small Business Technology Transfer USEFUL LINKS Contract Opportunities: FBO.gov FedConnect.net Grant Opportunities DOE Organization Chart Association of University Technology Managers (AUTM) Federal Laboratory Consortium (FLC) Feedback Contact us about Tech Transfer: Mary.McManmon@science.doe.gov Mary McManmon, 202-586-3509 link to Adobe PDF Reader link to Adobe Flash player Licensing Guide and Sample License The Technology Transfer Working Group (TTWG), made up of representatives from each DOE Laboratory and Facility, recently created a Licensing Guide and Sample License [762-KB PDF]. The Guide will serve to provide a general understanding of typical contract terms and provisions to help reduce both

244

Measuring Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Measurement Activity SI Units and Prefixes Conversions Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration...

245

Two-dimensional computational fluid dynamics and conduction simulations of heat transfer in window frames with internal cavities - Part 1: Cavities only  

E-Print Network (OSTI)

of heat fluxes from CFD and conduction simulations for theapproach to solve the conduction heat-transfer equation. TheFluid Dynamics and Conduction Simulations of Heat Transfer

Gustavsen, Arild; Kohler, Christian; Arasteh, Dariush; Curcija, Dragan

2003-01-01T23:59:59.000Z

246

Equational descriptions of languages ?  

E-Print Network (OSTI)

This paper is a survey on the equational descriptions of languages. The first part is devoted to Birkhoff’s and Reiterman’s theorems on equational descriptions of varieties. Eilenberg’s variety theorem and its successive generalizations form the second part. The more recent results on equational descriptions of lattices of languages are presented in the third part of the paper. Equations have been used for a long time in mathematics to provide a concise description of various mathematical objects. This article roughly follows a historical approach to present such equational descriptions for formal languages, ranging over a period of 45 years: from Schützenberger’s characterization of star-free languages [36] to the following recent result of [18]: Every lattice of languages admits an equational description. This evolution was made possible by a gradual abstraction of the notion of equation. The story really starts in 1935 with Birkhoff’s theorem on equational

Jean-éric Pin

2012-01-01T23:59:59.000Z

247

Efficient Calculation of Infrared Fluxes and Cooling Rates Using the Two-Stream Equations  

Science Conference Proceedings (OSTI)

The calculation of infrared radiative fluxes and cooling rates using the two-stream equations is discussed. It is argued that at infrared wavelengths the two-stream equations are best viewed as an approximation to the differential radiance, the ...

J. M. Edwards

1996-07-01T23:59:59.000Z

248

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.

Iso, Satoshi; Zhang, Sen

2011-01-01T23:59:59.000Z

249

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

250

A TWO-MOMENT RADIATION HYDRODYNAMICS MODULE IN ATHENA USING A TIME-EXPLICIT GODUNOV METHOD  

SciTech Connect

We describe a module for the Athena code that solves the gray equations of radiation hydrodynamics (RHD), based on the first two moments of the radiative transfer equation. We use a combination of explicit Godunov methods to advance the gas and radiation variables including the non-stiff source terms, and a local implicit method to integrate the stiff source terms. We adopt the M{sub 1} closure relation and include all leading source terms to O({beta}{tau}). We employ the reduced speed of light approximation (RSLA) with subcycling of the radiation variables in order to reduce computational costs. Our code is dimensionally unsplit in one, two, and three space dimensions and is parallelized using MPI. The streaming and diffusion limits are well described by the M{sub 1} closure model, and our implementation shows excellent behavior for a problem with a concentrated radiation source containing both regimes simultaneously. Our operator-split method is ideally suited for problems with a slowly varying radiation field and dynamical gas flows, in which the effect of the RSLA is minimal. We present an analysis of the dispersion relation of RHD linear waves highlighting the conditions of applicability for the RSLA. To demonstrate the accuracy of our method, we utilize a suite of radiation and RHD tests covering a broad range of regimes, including RHD waves, shocks, and equilibria, which show second-order convergence in most cases. As an application, we investigate radiation-driven ejection of a dusty, optically thick shell in the ISM. Finally, we compare the timing of our method with other well-known iterative schemes for the RHD equations. Our code implementation, Hyperion, is suitable for a wide variety of astrophysical applications and will be made freely available on the Web.

Skinner, M. Aaron; Ostriker, Eve C., E-mail: askinner@astro.umd.edu, E-mail: eco@astro.princeton.edu [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)

2013-06-01T23:59:59.000Z

251

A Two-moment Radiation Hydrodynamics Module in Athena Using a Time-explicit Godunov Method  

E-Print Network (OSTI)

We describe a module for the Athena code that solves the gray equations of radiation hydrodynamics (RHD), based on the first two moments of the radiative transfer equation. We use a combination of explicit Godunov methods to advance the gas and radiation variables including the non-stiff source terms, and a local implicit method to integrate the stiff source terms. We adopt the M1 closure relation and include all leading source terms. We employ the reduced speed of light approximation (RSLA) with subcycling of the radiation variables in order to reduce computational costs. Our code is dimensionally unsplit in one, two, and three space dimensions and is parallelized using MPI. The streaming and diffusion limits are well-described by the M1 closure model, and our implementation shows excellent behavior for a problem with a concentrated radiation source containing both regimes simultaneously. Our operator-split method is ideally suited for problems with a slowly varying radiation field and dynamical gas flows, i...

Skinner, M Aaron

2013-01-01T23:59:59.000Z

252

Parameterization of Outgoing Infrared Radiation Derived from Detailed Radiative Calculations  

Science Conference Proceedings (OSTI)

State-of-the-art radiative transfer models can calculate outgoing infrared (IR) irradiance at the top of the atmosphere (F) to an accuracy suitable for climate modeling given the proper atmospheric profiles of temperature and absorbing gases and ...

Starley L. Thompson; Stephen G. Warren

1982-12-01T23:59:59.000Z

253

Ghost Imaging with Blackbody Radiation  

E-Print Network (OSTI)

We present a theoretical study of ghost imaging by using blackbody radiation source. A Gaussian thin lens equation for the ghost imaging, which depends on both paths, is derived. The dependences of the visibility and quality of the image on the transverse size and temperature of the blackbody are studied. The main differences between the ghost imaging by using the blackbody radiation and by using the entangled photon pairs are image-forming equation, and the visibility and quality of the image

Yangjian Cai; Shiyao Zhu

2004-07-29T23:59:59.000Z

254

Nonequilibrium Electromagnetic Fluctuations: Heat Transfer and Interactions  

Science Conference Proceedings (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in nonequilibrium cases where each body, and the environment, is at a different temperature. The formalism tracks the radiation from each body and its scatterings by the other objects. We discuss the radiation from a cylinder, emphasizing its polarized nature, and obtain the heat transfer between a sphere and a plate, demonstrating the validity of proximity transfer approximation at close separations and arbitrary temperatures.

Krueger, Matthias; Kardar, Mehran [Massachusetts Institute of Technology, Department of Physics, Cambridge, Massachusetts 02139 (United States); Emig, Thorsten [Laboratoire de Physique Theorique et Modeles Statistiques, CNRS UMR 8626, Ba circumflex timent 100, Universite Paris-Sud, 91405 Orsay cedex (France)

2011-05-27T23:59:59.000Z

255

Derivation of new 3D discrete ordinate equations  

Science Conference Proceedings (OSTI)

The Sn equations have been the workhorse of deterministic radiation transport calculations for many years. Here we derive two new angular discretizations of the 3D transport equation. The first set of equations, derived using Lagrange interpolation and collocation, retains the classical Sn structure, with the main difference being how the scattering source is calculated. Because of the formal similarity with the classical S n equations, it should be possible to modify existing computer codes to take advantage of the new formulation. In addition, the new S n-like equations correctly capture delta function scattering. The second set of equations, derived using a Galerkin technique, does not retain the classical Sn structure because the streaming term is not diagonal. However, these equations can be cast into a form similar to existing methods developed to reduce ray effects. Numerical investigation of both sets of equations is under way. (authors)

Ahrens, C. D. [Colorado School of Mines, Dept. of Applied Mathematics and Statistics, Program in Nuclear Science and Engineering, Golden, CO 80401-1887 (United States)

2012-07-01T23:59:59.000Z

256

TECHNOLOGY TRANSFER  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

404-NOV. 1, 2000 404-NOV. 1, 2000 TECHNOLOGY TRANSFER COMMERCIALIZATION ACT OF 2000 VerDate 11-MAY-2000 04:52 Nov 16, 2000 Jkt 089139 PO 00000 Frm 00001 Fmt 6579 Sfmt 6579 E:\PUBLAW\PUBL404.106 APPS27 PsN: PUBL404 114 STAT. 1742 PUBLIC LAW 106-404-NOV. 1, 2000 Public Law 106-404 106th Congress An Act To improve the ability of Federal agencies to license federally owned inventions. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, SECTION 1. SHORT TITLE. This Act may be cited as the ''Technology Transfer Commer- cialization Act of 2000''. SEC. 2. FINDINGS. The Congress finds that- (1) the importance of linking our unparalleled network of over 700 Federal laboratories and our Nation's universities with United States industry continues to hold great promise

257

Electron Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

3 3 Pierre Kennepohl1,2 and Edward Solomon1* 1Department of Chemistry, Stanford University, Stanford, CA 94305 Electron transfer, or the act of moving an electron from one place to another, is amongst the simplest of chemical processes, yet certainly one of the most critical. The process of efficiently and controllably moving electrons around is one of the primary regulation mechanisms in biology. Without stringent control of electrons in living organisms, life could simply not exist. For example, photosynthesis and nitrogen fixation (to name but two of the most well-known biochemical activities) are driven by electron transfer processes. It is unsurprising, therefore, that much effort has been placed on understanding the fundamental principles that control and define the simple act of adding and/or removing electrons from chemical species.

258

A Numerical Study of Climatic Oscillations Using a Coupled Atmosphere–Ocean Primitive Equation Model  

Science Conference Proceedings (OSTI)

A coupled atmosphere-ocean primitive equation model is developed. It is a free-dimensional general circulation model, with two layers in the atmosphere and two layers in the ocean and includes solar radiation, longwave radiation, sensible heating,...

Xiong-Shan Chen

1984-03-01T23:59:59.000Z

259

Lanczos's equation to replace Dirac's equation ?  

E-Print Network (OSTI)

Lanczos's quaternionic interpretation of Dirac's equation provides a unified description for all elementary particles of spin 0, 1/2, 1, and 3/2. The Lagrangian formulation given by Einstein and Mayer in 1933 predicts two main classes of solutions. (1) Point like partons which come in two families, quarks and leptons. The correct fractional or integral electric and baryonic charges, and zero mass for the neutrino and the u-quark, are set by eigenvalue equations. The electro-weak interaction of the partons is the same as with the Standard model, with the same two free parameters: e and sin^2 theta. There is no need for a Higgs symmetry breaking mechanism. (2) Extended hadrons for which there is no simple eigenvalue equation for the mass. The strong interaction is essentially non-local. The pion mass and pion-nucleon coupling constant determine to first order the nucleon size, mass and anomalous magnetic moment.

Andre Gsponer; Jean-Pierre Hurni

2001-12-23T23:59:59.000Z

260

Modelling of Radiative Transfer in Light Sources  

E-Print Network (OSTI)

Institute of Applied Physics, RAS, 46 Ulyanov Street, Nizhny Novgorod 603950, Russia I. Y. Dodin and N. J particles could not travel faster than light. Hence, the final energy is estimated from Eq. 52 as a -1 Research through Grant No. 08-02-01209-a and the NNSA under the SSAA Program through DOE Research un- der

Eindhoven, Technische Universiteit

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

Statistical Description of Radiation Transfer in Clouds  

Science Conference Proceedings (OSTI)

The statistical characteristics of simulated cloud fields constructed based on Poisson point fluxes are studied. The input parameters of mathematical models of cloudiness include the cloud fraction and the mean horizontal size of clouds ...

Georgi A. Titov

1990-01-01T23:59:59.000Z

262

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

2004-10-14T23:59:59.000Z

263

Neutrino Transfer in Three Dimensions for Core-Collapse Supernovae. I. Static Configurations  

E-Print Network (OSTI)

We develop a numerical code to calculate the neutrino transfer with multi-energy and multi-angle in three dimensions (3D) for the study of core-collapse supernovae. The numerical code solves the Boltzmann equations for neutrino distributions by the discrete-ordinate (S_n) method with a fully implicit differencing for time advance. The Boltzmann equations are formulated in the inertial frame with collision terms being evaluated to the zeroth order of v/c. A basic set of neutrino reactions for three neutrino species is implemented together with a realistic equation of state of dense matter. The pair process is included approximately in order to keep the system linear. We present numerical results for a set of test problems to demonstrate the ability of the code. The numerical treatments of advection and collision terms are validated first in the diffusion and free streaming limits. Then we compute steady neutrino distributions for a background extracted from a spherically symmetric, general relativistic simulation of 15Msun star and compare them with the results in the latter computation. We also demonstrate multi-D capabilities of the 3D code solving neutrino transfers for artificially deformed supernova cores in 2D and 3D. Formal solutions along neutrino paths are utilized as exact solutions. We plan to apply this code to the 3D neutrino-radiation hydrodynamics simulations of supernovae. This is the first article in a series of reports on the development.

Kohsuke Sumiyoshi; Shoichi Yamada

2012-01-11T23:59:59.000Z

264

NETL: Technology Transfer - History of Technology Transfer  

History of Technology Transfer Technology transfer differs from providing services or products (e.g., acquisition) and financial assistance (e.g., ...

265

TUTORIALS: Copolymer Equation  

Science Conference Proceedings (OSTI)

Aug 17, 2007 ... This JAVA applet plots the copolymer equation and lets you explore the effect of varying the parameters. Theory and references are provided.

266

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

267

Fundamentals of Radiation Dosimetry  

Science Conference Proceedings (OSTI)

The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

Bos, Adrie J. J. [Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629JB Delft (Netherlands)

2011-05-05T23:59:59.000Z

268

Intermodal transfer of spent fuel  

Science Conference Proceedings (OSTI)

As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handier exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. A study of the movement of spent fuel casks through ports, including the loading and unloading of containers from cargo vessels, afforded an opportunity to estimate the radiation doses to those individuals handling the spent fuels with doses to the public along subsequent transportation routes of the fuel. A number of states require redundant inspections and for escorts over long distances on highways; thus handlers, inspectors, escort personnel, and others who are not normally classified as radiation workers may sustain doses high enough to warrant concern about occupational safety. This paper addresses the question of radiation safety for these workers. Data were obtained during, observation of the offloading of reactor spent fuel (research reactor spent fuel, in this instance) which included estimates of exposure times and distances for handlers, inspectors and other workers during offloading and overnight storage. Exposure times and distance were also for other workers, including crane operators, scale operators, security personnel and truck drivers. RADTRAN calculational models and parameter values then facilitated estimation of the dose to workers during incident-free ship-to-truck transfer of spent fuel.

Neuhauser, K.S. (Sandia National Labs., Albuquerque, NM (United States)); Weiner, R.F. (Western Washington Univ., Bellingham, WA (United States))

1991-01-01T23:59:59.000Z

269

About Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from...

270

Empirical Estimation of Daily Clear Sky Solar Radiation  

Science Conference Proceedings (OSTI)

The suitability of two simple empirical equations for the estimation of clear sky radiation was investigated. Results indicated that latitude and altitude were sufficient to estimate the empirical equation coefficients and that the estimates of ...

D. F. Heermann; G. J. Harrington; K. M. Stahl

1985-03-01T23:59:59.000Z

271

Handbook of heat transfer fundamentals (2nd edition)  

SciTech Connect

Recent advances in heat transfer are discussed, providing data and methodology to solve a wide range of heat transfer problems. The topics considered include: basic concepts of heat transfer, mathematical methods, thermophysical properties, conduction, numerical methods in heat transfer, natural convection, and internal duct flow and external flows in forced convection. Also addressed are: rarefied gases, electric and magnetic fields, condensation, boiling, two-phase flow, and radiation.

Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

1985-01-01T23:59:59.000Z

272

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

273

Partial Differential Equations  

Science Conference Proceedings (OSTI)

Table 3   Linear partial differential equations...fluids, electromagnetic) Damped waves, transmission lines Elliptic (c) Static case 2 Φ = f ( r ) 4th order (b) Elastic vibrations 4th order (c) Static

274

SIMULTANEOUS DIFFERENTIAL EQUATION COMPUTER  

DOE Patents (OSTI)

A description is given for an electronic simulator for a system of simultaneous differential equations, including nonlinear equations. As a specific example, a homogeneous nuclear reactor system including a reactor fluid, heat exchanger, and a steam boiler may be simulated, with the nonlinearity resulting from a consideration of temperature effects taken into account. The simulator includes three operational amplifiers, a multiplier, appropriate potential sources, and interconnecting R-C networks.

Collier, D.M.; Meeks, L.A.; Palmer, J.P.

1960-05-10T23:59:59.000Z

275

On the Relationship between Radiative Entropy and Temperature Distributions  

Science Conference Proceedings (OSTI)

The Earth can be viewed as a complex nonequilibrium system that exchanges primarily radiative energy and entropy with its surroundings. The energy balance equation provides an important constraint on the distribution of outgoing radiation since ...

Glen B. Lesins

1990-03-01T23:59:59.000Z

276

Alpha Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Basics of Radiation Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements. 4. A civil defense instrument (CD V-700) cannot detect the presence of radioactive materials that produce alpha radiation unless the radioactive materials also produce beta and/or gamma radiation.

277

Radiation: Radiation Control (Indiana)  

Energy.gov (U.S. Department of Energy (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,...

278

On the collective curvature radiation  

E-Print Network (OSTI)

The paper deals with the one possible mechanism of the pulsar radio emission, i.e., with the collective curvature radiation of the relativistic particle stream moving along the curved magnetospheric magnetic field lines. It is shown that the electromagnetic wave containing one cylindrical harmonic exp{is{\\phi}} can not be radiated by the curvature radiation mechanism, that corresponds to radiation of a charged particle moving along curved magnetic field lines. The point is that the particle in vacuum radiates the triplex of harmonics (s, s \\pm 1), so for the collective curvature radiation the wave polarization is very important and cannot be fixed a priori. For this reason the polarization of real unstable waves must be determined directly from the solution of wave equations for the media. Its electromagnetic properties should be described by the dielectric permittivity tensor \\^{\\epsilon}({\\omega},k,r), that contains the information on the reaction on all possible types of radiation.

Istomin, Ya N; Beskin, V S

2011-01-01T23:59:59.000Z

279

On Free Stochastic Differential Equations  

E-Print Network (OSTI)

The paper derives an equation for the Cauchy transform of the solution of a free stochastic differential equation (SDE). This new equation is used to solve several particular examples of free SDEs.

Kargin, Vladsislav

2011-01-01T23:59:59.000Z

280

Handbook of heat and mass transfer. Volume 1  

Science Conference Proceedings (OSTI)

This two-volume series, the work of more than 100 contributors, presents advanced topics in industrial heat and mass transfer operations and reactor design technology. Volume 1 emphasizes heat transfer operations. The contents are: Fundamentsls of momentum and heat transfer. Scaling in laminar and turbulent heat and mass transfer. Heat flux in the Benar-Rayleigh problem. Hydrodynamics of free liquid jets and their influence on heat transfer. Natural convection heat transfer to power law fluids. Natural convection in evaporating droplets. Principles of heat and mass transfer with liquid evaporation. Bubble nucleation, growth, and departure in boiling heat transfer. Forced convection boiling in uniformly heated channels. Transient boiling heat transfer under forced convection. Prediction of heat transfer during forced convection subcooled boiling. Liquid metal heat transfer in turbulent pipe flows. Mixed convection in buoyant plumes. Nucleation and growth in the diffusion cloud chamber. Convective and radiative heat transfer of flowing gaseous-solid suspensions. Heat transfer in gas-solid fluidized beds. Gas convection and unsteady conduction in fluid bed heat transfer. Heat transfer between tubes and gas-solid fluid beds. Periodic heat transfer through inhomogeneous layers.

Cheremisinoff, N.P.

1986-01-01T23:59:59.000Z

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

ARM - Publications: Science Team Meeting Documents: ARM Radiative...  

NLE Websites -- All DOE Office Websites (Extended Search)

ARM Radiative Transfer Modeling and Remote Sensing Clough, Shepard Atmospheric and Environmental Research Shephard, Mark Atmospheric and Environmental Research, Inc. Mlawer, Eli...

282

Solar Radiation Absorption due to Water Vapor: Advanced Broadband Parameterizations  

Science Conference Proceedings (OSTI)

Accurate parameterizations for calculating solar radiation absorption in the atmospheric column due to water vapor lines and continuum are proposed for use in broadband shortwave radiative transfer codes. The error in the absorption values is ...

Tatiana A. Tarasova; Boris A. Fomin

2000-11-01T23:59:59.000Z

283

Radiative Energy Budget Estimates for the 1979 Southwest Summer Monsoon  

Science Conference Proceedings (OSTI)

Obsemations of temperature moisture, cloud amount, cloud height and soil-derived aerosols are incorporated into radiative transfer models to yield estimates of the tropospheric and surface radiative energy budgets for the summer Monsoon of 1979. ...

Steven A. Ackerman; Stephen K. Cox

1987-10-01T23:59:59.000Z

284

Infrared Radiative Properties Of the Maritime Antarctic Atmosphere  

Science Conference Proceedings (OSTI)

The longwave radiation environment of the Antarctic Peninsula and Southern Ocean has been investigated using radiometric Fourier Transform Infrared (FTIR) measurements of atmospheric emission in conjunction with detailed radiative transfer ...

Dan Lubin

1994-01-01T23:59:59.000Z

285

Uncertainties in the Radiative Forcing Due to Sulfate Aerosols  

Science Conference Proceedings (OSTI)

Radiative transfer calculations based on a new sulfate distribution from a chemistry-transport model simulation have been performed. A wide range of sensitivity experiments have been performed to illustrate the large uncertainty in the radiative ...

Gunnar Myhre; Frode Stordal; Tore F. Berglen; Jostein K. Sundet; Ivar S. A. Isaksen

2004-03-01T23:59:59.000Z

286

Protection Against Ionizing Radiation in Extreme Radiation ...  

Science Conference Proceedings (OSTI)

Protection Against Ionizing Radiation in Extreme Radiation-resistant Microorganisms. ... Elucidated radiation protection by intracellular halides. ...

2013-05-01T23:59:59.000Z

287

Transferring Data at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Data Transferring Data Advice and Overview NERSC provides many facilities for storing data and performing analysis. However, transfering data - whether over the wide area network...

288

Jefferson Lab Technology Transfer  

What is Technology Transfer at Jefferson Lab? The transfer of technology (intellectual property) developed at JLab to the private sector is an ...

289

Information Equation of State  

E-Print Network (OSTI)

Landauer's principle is applied to information in the universe. Once stars began forming, the increasing proportion of matter at high stellar temperatures compensated for the expanding universe to provide a near constant information energy density. The information equation of state was close to the dark energy value, w = -1, for a wide range of redshifts, 10> z >0.8, over one half of cosmic time. A reasonable universe information bit content of only 10^87 bits is sufficient for information energy to account for all dark energy. A time varying equation of state with a direct link between dark energy and matter, and linked to star formation in particular, is clearly relevant to the cosmic coincidence problem.In answering the "Why now?" question we wonder "What next?" as we expect the information equation of state to tend towards w = 0 in the future.

Paul Gough

2007-09-05T23:59:59.000Z

290

Heat and mass transfer in a gas in a capillary induced by light with nonuniform intensity distribution over the beam cross section  

SciTech Connect

An analysis is presented of the heat and drift fluxes induced by velocity-selective light absorption in a single-component gas in a capillary tube. The light intensity distribution across the beam is assumed to have a Gaussian profile. Kinetic equations are solved numerically to calculate flux profiles and kinetic coefficients quantifying the contributions of surface and collisional mechanisms to light-induced transfer as functions of the Knudsen number, the ratio of the rate of radiative decay of the exited level and intermolecular collision frequency, accommodation coefficient, and the ratio of the tube radius to the light beam radius.

Chernyak, V. G., E-mail: vladimir.chernyak@usu.ru; Polikarpov, A. P., E-mail: alexey.polikarpov@usu.ru [Ural State University (Russian Federation)

2011-01-15T23:59:59.000Z

291

Loop Equation in Turbulence  

E-Print Network (OSTI)

The incompressible fluid dynamics is reformulated as dynamics of closed loops $C$ in coordinate space. This formulation allows to derive explicit functional equation for the generating functional $\\Psi[C]$ in inertial range of spatial scales, which allows the scaling solutions. The requirement of finite energy dissipation rate leads then to the Kolmogorov index. We find an exact steady solution of the loop equation in inertial range of the loop sizes. The generating functional decreases as $\\EXP{-A^{\\tt}}$ where $A=\\oint_C r \\wedge dr$ is the area inside the loop. The pdf for the velocity circulation $\\Gamma$ is Lorentzian, with the width $\\bar{\\Gamma} \\propto A^{\\tt} $.

Alexander A. Migdal

1993-03-23T23:59:59.000Z

292

Beta Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Beta Radiation 1. Beta radiation may travel meters in air and is moderately penetrating. 2. Beta radiation can penetrate human skin to the "germinal layer," where new skin cells...

293

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

294

Accelerating the transfer in Technology Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerating the transfer in Technology Transfer Accelerating the transfer in Technology Transfer Community Connections: Our link to Northern New Mexico Communities Latest Issue:Dec. 2013 - Jan. 2014 All Issues » submit Accelerating the transfer in Technology Transfer Express Licensing fast tracks commercialization. May 1, 2013 Division Leader Dave Pesiri Division Leader Dave Pesiri. Contact Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email Express Licensing program To better serve its partners, one of the first improvements the Lab's Technology Transfer Division (TT) has made is through its new Express Licensing initiative. Standardized license agreements and fee structures will remove long and complicated negotiations and decrease the time required to get patented Lab technology and software into the hands of

295

Electromagnetic Nature of Thermo-Mechanical Mass-Energy Transfer Due to Photon Diffusive Re-Emission and Propagation  

E-Print Network (OSTI)

energy transfer (i.e., via photon propagation) and commensurate mass-transfer trough material systems (parabolic differential equation), allowing infinite speed of thermal energy propagation (i.e., a change

Kostic, Milivoje M.

296

Radiation in Particle Simulations  

SciTech Connect

Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of megabars to thousands of gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known. The second method expands the electromagnetic field in normal modes (planewaves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion. The third method is a hybrid molecular dynamics/Monte Carlo (MD/MC) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions. The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc. This approach is inspired by the virial expansion method of equilibrium statistical mechanics. Using a combination of these methods we believe it is possible to do atomic-scale particle simulations of fusion ignition plasmas including the important effects of radiation emission and absorption.

More, R; Graziani, F; Glosli, J; Surh, M

2010-11-19T23:59:59.000Z

297

Momentum transfer from waves to particles  

SciTech Connect

Momentum transfer from an electromagnetic or electrostatic wave to an electron is calculated in the presence of friction, and is shown to be comparable to the one obtained from the ponderomotive force. Radiation reaction is analyzed as a special case and shown to be derivable from the classical limit of Compton scattering.

Schmidt, G.

1979-05-01T23:59:59.000Z

298

Numerical and experimental validation of heat and mass transfer during heat treatment of wood  

Science Conference Proceedings (OSTI)

In the current work, the three-dimensional Navier-Stokes equations along with the energy and concentration equations for the fluid coupled with the energy and mass conservation equations for the solid (wood) are solved to study the transient heat and ... Keywords: Luikov's model, conjugate problem, heat and mass transfer, high-temperature wood treatment, mathematical modeling, validation

R. Younsi; D. Kocaefe; S. Poncsak; T. Junjun

2007-05-01T23:59:59.000Z

299

Assessment of Hydrometeor Collection Rates from Exact and Approximate Equations. Part II: Numerical Bounding  

Science Conference Proceedings (OSTI)

Past microphysical investigations, including Part I of this study, have noted that the collection equation, when applied to the interaction between different hydrometeor species, can predict large mass transfer rates, even when an exact solution ...

Brian J. Gaudet; Jerome M. Schmidt

2007-01-01T23:59:59.000Z

300

Radiative Forcing of Stationary Planetary Waves  

Science Conference Proceedings (OSTI)

The stationary wave components of the planetary-scale circulation are maintained by topographic forcing and by latent and sensible heat transfers and radiation. These waves have a potential vorticity balance mainly due to vertically differential ...

Leo J. Donner; Hsiao-Lan Kuo

1984-10-01T23:59:59.000Z

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.


301

Optical Radiation  

Science Conference Proceedings (OSTI)

*. Bookmark and Share. Optical Radiation Measurements. Fees for services are located directly below the technical contacts ...

2013-04-09T23:59:59.000Z

302

Ionizing Radiation  

Science Conference Proceedings (OSTI)

*. Bookmark and Share. Ionizing Radiation Measurements. Fees for services are located directly below the technical contacts ...

2013-04-09T23:59:59.000Z

303

Some analytical models of radiating collapsing spheres  

Science Conference Proceedings (OSTI)

We present some analytical solutions to the Einstein equations, describing radiating collapsing spheres in the diffusion approximation. Solutions allow for modeling physical reasonable situations. The temperature is calculated for each solution, using a hyperbolic transport equation, which permits to exhibit the influence of relaxational effects on the dynamics of the system.

Herrera, L.; Di Prisco, A [Escuela de Fisica, Facultad de Ciencias, Universidad Central de Venezuela, Caracas (Venezuela); Ospino, J. [Area de Fisica Teorica. Facultad de Ciencias, Universidad de Salamanca Salamanca (Spain)

2006-08-15T23:59:59.000Z

304

Generalized Lorentz-Dirac Equation for a Strongly Coupled Gauge Theory  

SciTech Connect

We derive a semiclassical equation of motion for a 'composite' quark in strongly coupled large-N{sub c} N=4 super Yang-Mills theory, making use of the anti-de Sitter space/conformal field theory correspondence. The resulting nonlinear equation incorporates radiation damping, and reduces to the standard Lorentz-Dirac equation for external forces that are small on the scale of the quark Compton wavelength, but has no self-accelerating or preaccelerating solutions. From this equation one can read off a nonstandard dispersion relation for the quark, as well as a Lorentz-covariant formula for its radiation rate.

Chernicoff, Mariano; Garcia, J. Antonio; Gueijosa, Alberto [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico)

2009-06-19T23:59:59.000Z

305

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

306

RADIATION EFFECTS OF ALPHA PARTICLES ON URANIUM HEXAFLUORIDE  

SciTech Connect

Alpha irradiation of uranium hexafluoride results in the formation of fluorine and intermediate, solid uranium fluorides: these products react with each other, apparently by a radiation-induced process. to reform uranium hexifluoride. The number of molecules of uranium hexafluoride decomposed, excluding recombiapproximately 1 in the temperature range 21 to 87 deg C. Irradiation of a mixture of fluorine and uranium hexafluoride in a vessel containing uranium fluorides substantistes the postulated mechanism. At fluorine pressures of 50 to 100 mm Hg, there is an increase, rather than a decrease, in uranium hexafluoride pressure. Rates of both decomposition and recombination processes appear to depend only on the rates of radiation energy absorption. Equations formnulated to describe the combined decomposition and reformation reactions can be used to calculate equilibrium concentrations of uranium hexfluoride and fluorine when the intensity of the radiation source is defined. The effects of three diluent gases, helium, nitrogen and oxygen, were studied in an attempt to find possible electron transfer processes. (auth)

Bernhardt, H.A.; Davis, W. Jr.; Shiflett, C.H.

1958-06-01T23:59:59.000Z

307

On an Improvement of the Planck radiation Energy Distribution  

E-Print Network (OSTI)

The probability distribution function for thermodynamics and econophysics is obtained by solving an equilibrium equation. This approach is different from the common one of optimizing the entropy of the system or obtaining the state of maximum probability, which usually obtains as a result the Boltzmann distribution. The Gamma distribution is proposed as a better equation to describe the blackbody radiation in substitution of Planck's radiation equation. Also, a new form of entropy is proposed, that maintains the correct relation with the Clausius' formula.

Diego Saa

2006-03-15T23:59:59.000Z

308

About Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from naturally occurring radioactive materials such as uranium, thorium, radon, and certain forms of potassium and carbon. The air we breathe contains radon, the food we eat contains uranium and thorium from the soil, and our bodies contain radioactive forms of potassium and carbon. Cosmic radiation from the sun also contributes to our natural radiation dose. We also receive radiation doses from man-made sources such as X-rays, nuclear medical procedures, power plants, smoke detectors and older television sets. Some people, such as nuclear plant operators, flight crews, and nuclear medicine staff may also receive an occupational radiation dose.

309

Non-equilibrium electromagnetic fluctuations: Heat transfer and interactions  

E-Print Network (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in non-equilibrium cases where each body, and the environment, is at a different temperature. The formalism tracks the radiation from each body and its scatterings by the other objects. We discuss the radiation from a cylinder, emphasizing its polarized nature, and obtain the heat transfer between a sphere and a plate, demonstrating the validity of proximity transfer approximation at close separations and arbitrary temperatures.

Matthias Krüger; Thorsten Emig; Mehran Kardar

2011-02-18T23:59:59.000Z

310

Radiation Physics Portal  

Science Conference Proceedings (OSTI)

NIST Home > Radiation Physics Portal. Radiation Physics Portal. ... more. >> see all Radiation Physics programs and projects ... ...

2013-08-08T23:59:59.000Z

311

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

312

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

313

NERSC's Data Transfer Nodes  

NLE Websites -- All DOE Office Websites (Extended Search)

Data Transfer Nodes Data Transfer Nodes Data Transfer Nodes Overview The data transfer nodes are NERSC servers dedicated to performing transfers between NERSC data storage resources such as HPSS and the NERSC Global Filesystem (NGF), and storage resources at other sites including the Leadership Computing Facility at ORNL (Oak Ridge National Laboratory). These nodes are being managed (and monitored for performance) as part of a collaborative effort between ESnet, NERSC, and ORNL to enable high performance data movement over the high-bandwidth 10Gb ESnet wide-area network (WAN). Restrictions In order to keep the data transfer nodes performing optimally for data transfers, we request that users restrict interactive use of these systems to tasks that are related to preparing data for transfer or are directly

314

Radiative Heating Rates for Saharan Dust  

Science Conference Proceedings (OSTI)

A combined longwave and shortwave radiative transfer model was used to determine effects of Saharan dust on the radiative fluxes and heating/cooling rates in the atmosphere. Cases are treated for cloud-free and overcast conditions over the ocean ...

Toby N. Carlson; Stanley G. Benjamin

1980-01-01T23:59:59.000Z

315

Federal Laboratory Technology Transfer  

Science Conference Proceedings (OSTI)

... Department of Energy (DOE) ... and business development involved in successful technology transfer. 8. Government-industry interactions. ...

2012-11-14T23:59:59.000Z

316

SRNL - Technology Transfer - Home  

Technology Transfer. Research and Development Savannah River Nuclear Solutions, LLC (SRNS) scientists and engineers develop technologies designed to improve ...

317

Tech Transfer Report 2000  

Science Conference Proceedings (OSTI)

Page 1. Summary Report on Federal Laboratory Technology Transfer FY 2003 Activity Metrics and Outcomes 2004 Report ...

2010-07-27T23:59:59.000Z

318

Radiation Cataract  

NLE Websites -- All DOE Office Websites (Extended Search)

radiation including patients undergoing diagnostic CT scans or radiotherapy, atomic bomb survivors, residents of radioactively contaminated buildings, victims of the...

319

Kinetic equations for a density matrix describing nonlinear effects in spectral line wings  

Science Conference Proceedings (OSTI)

Kinetic quantum equations are derived for a density matrix with collision integrals describing nonlinear effects in spectra line wings. These equations take into account the earlier established inequality of the spectral densities of Einstein coefficients for absorption and stimulated radiation emission by a two-level quantum system in the far wing of a spectral line in the case of frequent collisions. The relationship of the absorption and stimulated emission probabilities with the characteristics of radiation and an elementary scattering event is found.

Parkhomenko, A. I., E-mail: par@iae.nsk.su; Shalagin, A. M., E-mail: shalagin@iae.nsk.su [Russian Academy of Sciences, Institute of Automation and Electrometry, Siberian Branch (Russian Federation)

2011-11-15T23:59:59.000Z

320

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

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 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

322

A unified numerical framework model for simulating flow, transport, and heat transfer in porous and fractured media  

E-Print Network (OSTI)

or chemical species in a multiphase porous medium system canand radiation in a multiphase, multicomponent, porous mediummultiphase flow, multicomponent transport, and heat transfer in porous

Wu, Yu-Shu

2004-01-01T23:59:59.000Z

323

Handbook of heat and mass transfer. Volume 2  

Science Conference Proceedings (OSTI)

This two-volume series, the work of more than 100 contributors, presents advanced topics in industrial heat and mass transfer operations and reactor design technology. Volume 2 emphasizes mass transfer and reactor design. Some of the contents discussed are: MASS TRANSFER PRINCIPLES - Effect of turbulence promoters on mass transfer. Mass transfer principles with homogeneous and heterogeneous reactions. Convective diffusion with reactions in a tube. Transient mass transfer onto small particles and drops. Modeling heat and mass transport in falling liquid films. Heat and mass transfer in film absorption. Multicomponent mass transfer: theory and applications. Diffusion limitation for reaction in porous catalysts. Kinetics and mechanisms of catalytic deactivation. DISTILLATION AND EXTRACTION - Generalized equations of state for process design. Mixture boiling. Estimating vapor pressure from normal boiling points of hydrocarbons. Estimating liquid and vapor molar fractions in distillation columns. Principles of multicomponent distillation. Generalized design methods for multicomponent distillation. Interfacial films in inorganic substances extraction. Liquid-liquid extraction in suspended slugs. MULTIPHASE REACTOR SYSTEMS - Reaction and mass transport in two-phase reactors. Mass transfer and kinetics in three-phase reactors. Estimating liquid film mass transfer coefficients in randomly packed columns. Designing packed tower wet scrubbers - emphasis on nitrogen oxides. Gas absorption in aerated mixers. Axial dispersion and heat transfer in gas-liquid bubble columns. Operation and design of trickle-bed reactors.

Cheremisinoff, N.P.

1986-01-01T23:59:59.000Z

324

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

325

Transfer Credit Approval Form For Transfer Terms and Exchange Programs  

E-Print Network (OSTI)

Transfer Credit Approval Form For Transfer Terms and Exchange Programs CONTINUED Student/transfer term is not a Dartmouth-sponsored program. ______ The regulations for exchange/transfer terms of the COI will review my transfer term application and I may only receive Dartmouth credit for a transfer

Myers, Lawrence C.

326

Spinor wave equation of photon  

E-Print Network (OSTI)

In this paper, we give the spinor wave equations of free and unfree photon, which are the differential equation of space-time one order. For the free photon, the spinor wave equations are covariant, and the spinors $\\psi$ are corresponding to the the reducibility representations $D^{10}+D^{01}$ and $D^{10}+D^{01}+D^{1/2 1/2}$ of the proper Lorentz group.

Xiang-Yao Wu; Bo-Jun Zhang; Xiao-Jing Liu; Si-Qi Zhang; Jing Wang; Hong Li; Xi-Hui Fan; Jing-Wu Li

2012-12-14T23:59:59.000Z

327

Nonlinear graphene plasmonics: amplitude equation  

E-Print Network (OSTI)

Using perturbation expansion of Maxwell equations, the amplitude equation is derived for nonlinear TM and TE surface plasmon waves supported by graphene. The equation describes interplay between in-plane beam diffraction and nonlinerity due to light intensity induced corrections to graphene conductivity and susceptibility of dielectrics. For strongly localized TM plasmons, graphene is found to bring the superior contribution to the overall nonlinearity. In contrast, nonlinear response of the substrate and cladding dielectrics can become dominant for weakly localized TE plasmons.

Gorbach, A V

2013-01-01T23:59:59.000Z

328

Rational Approximation for a Quasilinear Parabolic Equation  

E-Print Network (OSTI)

Approximation theorems, analogous to known results for linear elliptic equations, are obtained for solutions of the heat equation. Via the Cole-Hopf transformation, this gives rise to approximation theorems for a nonlinear parabolic equation, Burgers' equation.

P. M. Gauthier; N. Tarkhanov

2007-09-22T23:59:59.000Z

329

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.

Townsend, Harold E. (Campbell, CA); Barbanti, Giancarlo (Cupertino, CA)

1994-01-01T23:59:59.000Z

330

Iterative solution of differential equations  

E-Print Network (OSTI)

We discuss alternative iteration methods for differential equations. We provide a convergence proof for exactly solvable examples and show more convenient formulas for nontrivial problems.

Paolo Amore; Hakan Ciftci; Francisco M. Fernandez

2006-09-29T23:59:59.000Z

331

Technology Transfer: About the Technology Transfer Department  

NLE Websites -- All DOE Office Websites (Extended Search)

About the Technology Transfer and Intellectual Property Management About the Technology Transfer and Intellectual Property Management Department The Technology Transfer Department helps move technologies from the Lab to the marketplace to benefit society and the U. S. economy. We accomplish this through developing and managing an array of partnerships with the private and public sectors. What We Do We license a wide range of cutting-edge technologies to companies that have the financial, R & D, manufacturing, marketing, and managerial capabilities to successfully commercialize Lab inventions. In addition, we manage lab-industry research partnerships, ensure that inventions receive appropriate patent or copyright protection, license technology to start-up companies, distribute royalties to the Lab and to inventors and serve as

332

NREL: Technology Transfer - About Technology Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

About Technology Transfer About Technology Transfer Through technology partnerships, NREL seeks to reduce private sector risk and enable investment in the adoption of renewable energy and energy efficiency technologies. The transfer of these technologies to the marketplace helps displace oil, reduce carbon emissions, and increase U.S. industry competitiveness. Principles NREL develops and implements technology partnerships based on the standards established by the following principles: Balancing Public and Private Interest Form partnerships that serve the public interest and advance U.S. Department of Energy goals. Demonstrate appropriate stewardship of publicly funded assets, yielding national benefits. Provide value to the commercial partner. Focusing on Outcomes Develop mutually beneficial collaborations through processes, which are

333

Memristive Transfer Matrices  

E-Print Network (OSTI)

An electrical analysis is performed for a memristor crossbar array integrated with operational amplifiers including the effects of parasitic or contact resistances. It is shown that the memristor crossbar array can act as a transfer matrix for a multiple input-multiple output signal processing system. Special cases of the transfer matrix are described related to reconfigurable analog filters, waveform generators, analog computing, and pattern similarity. Keywords: transfer matrix, memristor, analog electronics, crossbar, operational amplifier, reconfigurable electronics

Mouttet, Blaise

2010-01-01T23:59:59.000Z

334

Jefferson Lab Technology Transfer  

This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to any browser. Concerns? Technology Transfer.

335

NETL: Technology Transfer - DOE  

Home > Technology Transfer. ... and cheaper to design future power plants. ... we welcome the opportunity to build mutually beneficial partnerships with industry, ...

336

NREL: Technology Transfer - Contacts  

National Renewable Energy Laboratory Technology Transfer Contacts. Here you'll find contact information and resources to help answer any questions you may have about ...

337

SRNL - Technology Transfer - Ombudsman  

... complete fairness in the transfer of federally funded technologies into the marketplace for the benefit of the U.S. economy.

338

Partnerships and Technology Transfer  

Economic Development Overview. ORNL's Partnerships Staff works with a number of partners in the region, State, and across the nation to help transfer ORNL-developed ...

339

MATERIALS TRANSFER AGREEMENT  

NLE Websites -- All DOE Office Websites (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...

340

Heat transfer dynamics  

Science Conference Proceedings (OSTI)

As heat transfer technology increases in complexity, it becomes more difficult for those without thermal dynamics engineering training to choose between competitive heat transfer systems offered to meet their drying requirements. A step back to the basics of heat transfer can help professional managers and papermakers make informed decisions on alternative equipment and methods. The primary forms of heat and mass transfer are reviewed with emphasis on the basics, so a practical understanding of each is gained. Finally, the principles and benefits of generating infrared energy by combusting a gaseous hydrocarbon fuel are explained.

Smith, T.M. (Marsden, Inc., Pennsauken, NJ (United States))

1994-08-01T23:59:59.000Z

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

Facility Survey & Transfer  

Energy.gov (U.S. Department of Energy (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.

342

Technology Transfer: For Industry  

NLE Websites -- All DOE Office Websites (Extended Search)

Available Technologies Licensing Berkeley Lab Technologies Partnering with Berkeley Lab Contact Us Receive Customized Tech Alerts Tech Transfer Site Map Last updated: 09172009...

343

Radiation Information  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Information << Timeline >> Content on this page requires a newer version of Adobe Flash Player. Get Adobe Flash player July 31, 1942 The Army Corp of Engineers leases...

344

Evidence for frequency-dependent extracellular impedance from the transfer function between extracellular and intracellular potentials  

Science Conference Proceedings (OSTI)

We examine the properties of the transfer function F T ¿=¿V m / V LFP between the intracellular membrane potential (V m ) and the local field ... Keywords: Computational models, EEG, Extracellular resistivity, Intracellular recordings, Local field potentials, Maxwell equations

Claude Bédard; Serafim Rodrigues; Noah Roy; Diego Contreras; Alain Destexhe

2010-12-01T23:59:59.000Z

345

Conservation laws of semidiscrete canonical Hamiltonian equations  

E-Print Network (OSTI)

There are many evolution partial differential equations which can be cast into Hamiltonian form. Conservation laws of these equations are related to one-parameter Hamiltonian symmetries admitted by the PDEs. The same result holds for semidiscrete Hamiltonian equations. In this paper we consider semidiscrete canonical Hamiltonian equations. Using symmetries, we find conservation laws for the semidiscretized nonlinear wave equation and Schrodinger equation.

Roman Kozlov

2004-02-25T23:59:59.000Z

346

A Coupled Model for Laplace's Tidal Equations in a Fluid with One Horizontal Dimension and Variable Depth  

Science Conference Proceedings (OSTI)

Tide–topography interactions dominate the transfer of tidal energy from large to small scales. At present, it is poorly understood how low-mode internal tides reflect and scatter along the continental margins. Here, the coupling equations for ...

Samuel M. Kelly; Nicole L. Jones; Jonathan D. Nash

2013-08-01T23:59:59.000Z

347

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

348

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

SciTech Connect

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

349

Heat transfer in freeboard region of fluidized beds  

SciTech Connect

This research involved the study of heat transfer and fluid mechanic characteristics around a horizontal tube in the freeboard region of fluidized beds. Heat transfer coefficients were experimetnally measured for different bed temperatures, particle sizes, gas flow rates, and tube elevations in the freeboard region of air fluidized beds at atmospheric pressure. Local heat transfer coefficients were found to vary significantly with angular position around the tube. Average heat transfer coefficients were found to decrease with increasing freeboard tube elevation and approach the values for gas convection plus radiation for any given gas velocity. For a fixed tube elevation, heat transfer coefficients generally increased with increasing gas velocity and with high particle entrainment they can approach the magnitudes found for immersed tubes. Heat transfer coefficients were also found to increase with increasing bed temperature. It was concluded that this increase is partly due to increase of radiative heat transfer and partly due to change of thermal properties of the fluidizing gas and particles. To investigate the fluid mechanic behavior of gas and particles around a freeboard tube, transient particle tube contacts were measured with a special capacitance probe in room temperature experiments. The results indicated that the tube surface experiences alternating dense and lean phase contacts. Quantitative information for local characteristics was obtained from the capacitance signals and used to develop a phenomenological model for prediction of the heat transfer coefficients around freeboard tubes. The packet renewal theory was modified to account for the dense phase heat transfer and a new model was suggested for the lean phase heat transfer. Finally, an empirical freeboard heat transfer correlation was developed from functional analysis of the freeboard heat transfer data using nondimensional groups representing gas velocity and tube elevation.

Biyikli, S.; Tuzla, K.; Chen, J.C.

1983-10-01T23:59:59.000Z

350

Radiator Labs | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Radiator Labs Radiator Labs National Clean Energy Business Plan Competition Radiator Labs Columbia University More than 14 million housing units, or 10 percent of the national housing stock, is heated by steam and hot water. Steam heating, which represents the majority of this market, is particularly inefficient, and is characterized by a central source of steam generation with a convective 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 a building as a single zone keeping the coldest apartment above a minimum statutory temperature. This results in overheating of the other spaces in the building due to differences in exposure, level of insulation, distribution system heating,

351

Radiator Labs | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Competition » Radiator Labs Competition » Radiator Labs National Clean Energy Business Plan Competition Radiator Labs Columbia University More than 14 million housing units, or 10 percent of the national housing stock, is heated by steam and hot water. Steam heating, which represents the majority of this market, is particularly inefficient, and is characterized by a central source of steam generation with a convective 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 a building as a single zone keeping the coldest apartment above a minimum statutory temperature. This results in overheating of the other spaces in the building due to differences in exposure, level of insulation, distribution system heating,

352

Radiator Labs | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Competition » Radiator Labs Competition » Radiator Labs National Clean Energy Business Plan Competition Radiator Labs Columbia University More than 14 million housing units, or 10 percent of the national housing stock, is heated by steam and hot water. Steam heating, which represents the majority of this market, is particularly inefficient, and is characterized by a central source of steam generation with a convective 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 a building as a single zone keeping the coldest apartment above a minimum statutory temperature. This results in overheating of the other spaces in the building due to differences in exposure, level of insulation, distribution system heating,

353

MULTI-POINT RADIATION MONITOR  

SciTech Connect

A unique radiation monitor has been developed for performing wide-area field surveys for radiation sources. This device integrates the real-time output of multiple radiation detectors into a hand-held personal computer (e.g., a PDA) containing an intuitive graphical user interface. An independent hardware module supplies high voltage to the detectors and contains a rapid sampling system for transferring the detector count rates through an interface to the PDA. The imbedded firmware can be changed for various applications using a programmable memory card. As presently configured, the instrument contains a series of Geiger-Mueller (GM) tubes in a flexible detector string. This linear array of multiple sensors can be used by US Coast Guard and Customs container inspection personnel to measure radiation intensity in stacks of transport containers where physical access is impeded.

Hofstetter, K; Donna Beals, D; Ken Odell, K; Robert Eakle, R; Russell Huffman, R; Larry Harpring, L

2006-05-12T23:59:59.000Z

354

Numerical Modeling of Heat Pipe Radiator and Fin Size Optimization for Low and No Gravity Environments.  

E-Print Network (OSTI)

??A heat-pipe radiator element has been designed and modeled to study the efficiency of heat transfer for low and no gravity environments, like in lunar… (more)

Bieger, Virginia Ruth

2013-01-01T23:59:59.000Z

355

A search on Dirac equation  

E-Print Network (OSTI)

The solutions, in terms of orthogonal polynomials, of Dirac equation with analytically solvable potentials are investigated within a novel formalism by transforming the relativistic equation into a Schrodinger like one. Earlier results are discussed in a unified framework and certain solutions of a large class of potentials are given.

M Kocak; B Gonul

2007-02-15T23:59:59.000Z

356

Global existence result for phase transformations with heat transfer in shape memory alloys  

E-Print Network (OSTI)

We consider three-dimensional models for rate-independent processes describing materials undergoing phase transformations with heat transfer. The problem is formulated within the framework of generalized standard solids by the coupling of the momentum equilibrium equation and the flow rule with the heat transfer equation. Under appropriate regularity assumptions on the initial data, we prove the existence a global solution for this thermodynamically consistent system, by using a fixed-point argument combined with global energy estimates.

Paoli, Laetitia

2011-01-01T23:59:59.000Z

357

Cloud-Induced Infrared Radiative Heating and Its Implications for Large-Scale Tropical Circulations  

Science Conference Proceedings (OSTI)

Three-dimensional global distributions of longwave radiative cooling for the summer of 1988 and the winter of 1989 are generated from radiative transfer calculations using European Centre for Medium-Range Weather Forecasts temperature and ...

Byung-Ju Sohn

1999-08-01T23:59:59.000Z

358

The Effect of Clouds on the Earth's Solar and Infrared Radiation Budgets  

Science Conference Proceedings (OSTI)

The effect of global cloudiness on the solar and infrared components of the earth's radiation balance is studied in general circulation model experiments. A wintertime simulation is conducted in which the cloud radiative transfer calculations use ...

Gerald F. Herman; Man-Li C. Wu; Winthrop T. Johnson

1980-06-01T23:59:59.000Z

359

Spectral Absorption of Solar Radiation in Cloudy Atmospheres: A 20 cm?1 Model  

Science Conference Proceedings (OSTI)

The spectral of solar radiation in typical water clouds is determined using a radiative transfer model based on LOWTRAN transmission functions at a 20 cm?1 resolution and Monte Carlo simulations of photon pathlength distributions. Relative ...

Roger Davies; William L. Ridgway; Kyung-Eak Kim

1984-07-01T23:59:59.000Z

360

The CERES/ARM/GEWEX Experiment (CAGEX) for the Retrieval of Radiative Fluxes with Satellite Data  

Science Conference Proceedings (OSTI)

Results from a temporally intensive, limited area, radiative transfer model experiment are on-line for investigating the vertical profile of shortwave and longwave radiative fluxes from the surface to the top of the atmosphere (TOA). The CERES/...

Thomas P. Charlock; Timothy L. Alberta

1996-11-01T23:59:59.000Z

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.


361

Downward Longwave Surface Radiation from Sun-Synchronous Satellite Data: Validation of Methodology  

Science Conference Proceedings (OSTI)

An extensive study has been carried out to validate a satellite technique for estimating downward longwave radiation at the surface. The technique, mostly developed earlier, uses operational sun-synchronous satellite data and a radiative transfer ...

Wayne L. Darnell; Shashi K. Gupta; W. Frank Staylor

1986-07-01T23:59:59.000Z

362

The Contributions of Several Absorption Bands to Stratospheric Radiative Dissipation Rates  

Science Conference Proceedings (OSTI)

A narrowband (5 cm?1) radiation transfer scheme has been used to calculate scale-dependent radiative dissipation rates for finite-amplitude temperature disturbances. Eight bands of five atmospheric trace gases have been examined. As previously ...

Gerd Breßer; Steven Pawson

1996-05-01T23:59:59.000Z

363

Calculating Monthly Radiative Fluxes and Heating Rates fromMonthly Cloud Observations  

Science Conference Proceedings (OSTI)

The radiative transfer model from NCAR’s general circulation model CCM3 is modified to calculate monthly radiative fluxes and heating rates from monthly observations of cloud properties from the International Satellite Cloud Climatology Project ...

John W. Bergman; Harry H. Hendon

1998-12-01T23:59:59.000Z

364

Radiative Effects on Turbulent Temperature Spectra and Budgets in the Planetary Boundary Layer  

Science Conference Proceedings (OSTI)

The effects of radiative energy transfer on turbulent temperature fields are studied, and preliminary estimates show the infrared “radiative dissipation” mechanism to be dominant. Spectral computations for the idealized homogeneous-isotropic case ...

M. Coantic; O. Simonin

1984-09-01T23:59:59.000Z

365

Knowledge transfer frameworks  

Science Conference Proceedings (OSTI)

While theories abound concerning knowledge transfer in organisations, little empirical work has been undertaken to assess any possible relationship between repositories of knowledge and those responsible for the use of knowledge. This paper develops ... Keywords: hybrid approach, knowledge administration, knowledge management, knowledge storage, knowledge transfer framework

Sajjad M Jasimuddin; Nigel Connell; Jonathan H Klein

2012-05-01T23:59:59.000Z

366

Transfers | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Transfers Transfers Transfers Transfer means a change of an employee, from one Federal government branch (executive, legislative, judicial) to another or from one agency to another without a break in service of 1 full work day. Below are a few tips to better assist you when you transer agencies: If you have any dependents you must complete a standard Form 2809 during new employee orientation as this information does not transfer over automatically. You will not be able to change your coverage until open season or a life changing event occurs. At the time of new employee orientation you must provide your most recent leave and earning statement (LES) so that your leave may be updated accordingly. If you do not provide us with this document it will take approximately 6 weeks before your annual and sick leave is updated.

367

Data Transfer Examples  

NLE Websites -- All DOE Office Websites (Extended Search)

» Data Transfer Examples » Data Transfer Examples Data Transfer Examples Moving data to Projectb Projectb is where data should be written from jobs running on the cluster or Gpints. There are intermediate files or bad results from a run that didn't work out that don't need to be saved. By running these jobs in the SCRATCH areas, these files will be deleted for you by the puge. If you run in the SANDBOX, you will have to clean up after yourselves. Batch Scheduled Transfers Use any queues to schedule jobs that move data to Projectb. A basic transfer script is here: kmfagnan@genepool12 ~ $ cat data_to_projb.sh #!/bin/bash -l #$ -N data2projb /projectb/scratch// kmfagnan@genepool12 ~ $ qsub data_to_projb.sh

368

Multinucleon transfer reactions  

SciTech Connect

The development of higher energies and better resolution in heavy-ion beams has led to a resurgence of interest in transfer reactions at energies well above the Coulomb barrier. Direct reactions with heavy ions are discussed in some detail. Heavy-ion reactions open up the possibility of new methods of spectroscopy, e.g., elastic transfer. Differential cross sections for heavy-ion ' transfer reactions are often featureless; however, some data show diffractive effects. The high angular momenta associated with recoil effects in heavy-ion reactions can be exploited to perform selective spectroscopy on light nuclei. Although most heavy-iontransfer data suggest that reactions proceed in a direct fashion, recent experiments indicate the presence of second-order multistep processes. Correlated nucleon transfer and transfer of many nucleons (e.g., (12C, alpha )) are also being investigated. (20 figures, 3 tables, 93 references) (RWR)

Scott, D.K.

1973-08-01T23:59:59.000Z

369

Radiative Importance of ThinŽ Liquid Water Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

Program Program Accomplishments of the Instantaneous Radiative Flux (IRF) Working Group August 2006 AERI Observations at Southern Great Plains Improve Infrared Radiative Transfer Models Turner et al., JAS, 2004 * AERI observations used to evaluate clear sky IR radiative transfer models * Long-term comparisons have improved - Spectral line database parameters - Water vapor continuum absorption models * Reduced errors in computation of downwelling radiative IR flux by approx 4; current uncertainty is on the order of 1.5 W/m 2 AERI - (Pre-ARM Model) AERI - (Model in 2003) 1 RU = 1 mW / (m 2 sr cm -1 ) Excellent Agreement in Clear Sky Shortwave Radiative Transfer Between Obs and Calcs Shortwave Flux Bias (Solid) Shortwave Flux RMS (Hatched) W m -2 * Comparison of shortwave radiative flux at the surface

370

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 in such an exchanger are derived and solved leading to an optimization problem. In this problem, the optimal subdivision of heat transfer surface to minimize required overall heat transfer surface, under certain restricted conditions, is sought. It is shown that the off-center nozzle location can be selected judiciously so as to maintain (or even improve heat transfer) while reducing the gross shellside pressure loss. Thus, the pumping costs are minimized without sacrificing heat transfer.

Singh, K. P.

1979-01-01T23:59:59.000Z

371

Definition of Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of...

372

How to Detect Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

How to Detect Radiation How to Survey Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Procedure Demonstration Detection How...

373

Handbook of single-phase convective heat transfer  

Science Conference Proceedings (OSTI)

This book presents a comprehensive collection of convective heat transfer basics, methods of calculations, tables, charts and design parameters involving single-phase flows - the most commonly experienced mode in heat transfer problems. Topics covered include natural and forced convection under a wise variety of design conditions, such as ducts, crossflows, turbulent conditions, transitional states, curved and coiled ducts, over rods in metals and through bends, valves and fittings. The book provides sections on radiation interaction and fouling conditions.

Kakac, S.; Shah, R.K.; Aung, W.

1987-01-01T23:59:59.000Z

374

A quantum description of radiation damping and the free induction signal in magnetic resonance  

Science Conference Proceedings (OSTI)

We apply the methods of cavity quantum electrodynamics (CQED), to obtain a microscopic and fully quantum-mechanical picture of radiation damping in magnetic resonance, and the nascent formation of the free induction signal. Numerical solution of the Tavis-Cummings model - i.e., multiple spins 1/2 coupled to a lossless single-mode cavity - shows in fine detail the transfer of Zeeman energy, via spin coherence, to excite the cavity - represented here by a quantized LC resonator. The case of a single spin is also solved analytically. Although the motion of the Bloch vector is non-classical, we nonetheless show that the quantum mechanical Rabi nutation frequency (as enhanced by cavity coupling and stimulated emission) gives realistic estimates of macroscopic signal strength and the radiation damping constant in nuclear magnetic resonance. We also show how to introduce dissipation: cavity losses by means of a master equation, and relaxation by the phenomenological method of Bloch. The failure to obtain the full Bloch equations (unless semi-classical conditions are imposed on the cavity) is discussed in light of similar issues arising in CQED (and in earlier work in magnetic resonance as well), as are certain problems relative to quantization of the electromagnetic near-field.

Tropp, James [General Electric Healthcare Technologies, 47697 Westinghouse Drive, Fremont, California 94539 (United States)

2013-07-07T23:59:59.000Z

375

Technology transfer 1994  

SciTech Connect

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.

1994-01-01T23:59:59.000Z

376

Temporal Accuracy of the Solution of Nonequilibrium Radiation...  

National Nuclear Security Administration (NNSA)

Accuracy of the Solution of Nonequilibrium Radiation Diffusion Equations V.A. Mousseau, * R.M. Rauenzahn, * D.A. Knoll * * Los Alamos National Laboratory, T-3, Fluid Dynamics, MS...

377

High performance radiation transport simulations: preparing for Titan  

Science Conference Proceedings (OSTI)

In this paper we describe the Denovo code system. Denovo solves the six-dimensional, steady-state, linear Boltzmann transport equation, of central importance to nuclear technology applications such as reactor core analysis (neutronics), radiation shielding, ...

C. Baker; G. Davidson; T. M. Evans; S. Hamilton; J. Jarrell; W. Joubert

2012-11-01T23:59:59.000Z

378

High performance radiation transport simulations: Preparing for TITAN  

Science Conference Proceedings (OSTI)

In this paper we describe the Denovo code system. Denovo solves the six-dimensional, steady-state, linear Boltzmann transport equation, of central importance to nuclear technology applications such as reactor core analysis (neutronics), radiation shielding, ...

C. Baker, G. Davidson, T. M. Evans, S. Hamilton, J. Jarrell, W. Joubert

2012-11-01T23:59:59.000Z

379

Cryogenic apparatus for study of near-field heat transfer  

Science Conference Proceedings (OSTI)

For bodies spaced in vacuum at distances shorter than the wavelength of the thermal radiation, radiative heat transfer substantially increases due to the contribution of evanescent electromagnetic waves. Experimental data on heat transfer in near-field regime are scarce. We have designed a cryogenic apparatus for the study of heat transfer over microscopic distances between metallic and non-metallic surfaces. Using a mechanical positioning system, a planeparallel gap between the samples, concentric disks, each 35 mm in diameter, is set and varied from 10{sup 0} to 10{sup 3} {mu}m. The heat transferred from the hot (10 - 100 K) to the cold sample ({approx}5 K) sinks into a liquid helium bath through a thermal resistor, serving as a heat flux meter. Transferred heat power within {approx}2 nW/cm{sup 2} and {approx}30 {mu}W/cm{sup 2} is derived from the temperature drop along the thermal resistor. For tungsten samples, the distance of the near-field effect onset was inversely proportional to temperature and the heat power increase was observed up to three orders of magnitude greater than the power of far-field radiative heat transfer.

Kralik, T.; Hanzelka, P.; Musilova, V.; Srnka, A.; Zobac, M. [Institute of Scientific Instruments of the ASCR, v.v.i., Kralovopolska 147, Brno (Czech Republic)

2011-05-15T23:59:59.000Z

380

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

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

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

382

Adiabatic quantum state transfer in non-uniform triple-quantum-dot system  

E-Print Network (OSTI)

We introduce an adiabatic quantum state transfer scheme in a non-uniform coupled triple-quantum-dot system. By adiabatically varying the external gate voltage applied on the sender and receiver, the electron can be transferred between them with high fidelity. By numerically solving the master equation for a system with always-on interaction, it is indicated that the transfer fidelity depends on the ration between the peak voltage and the maximum coupling constants. The effect of coupling mismatch on the transfer fidelity is also investigated and it is shown that there is a relatively large tolerance range to permit high fidelity quantum state transfer.

Bing Chen; Wei Fan; Yan Xu

2010-10-18T23:59:59.000Z

383

FEHM: finite element heat and mass transfer code  

DOE Green Energy (OSTI)

The finite element heat and mass (FEHM) transfer code is a computer code developed to simulate geothermal and hot dry rock reservoirs. It is also applicable to natural-state studies of geothermal systems and ground-water flow. It solves the equations of heat and mass transfer for multiphase flow in porous and permeable media using the finite element method. The code also has provisions for a noncoupled tracer; that is, the tracer solutions do not affect the heat and mass transfer solutions. It can simulate two-dimensional, two-dimensional radial, or three-dimensional geometries. A summary of the equations in the model, the numerical solution procedure, and model verification and validation are provided in this report. A user's guide and sample problems are included in the appendices. 17 refs., 10 figs., 4 tabs.

Zyvoloski, G.; Dash, Z.; Kelkar, S.

1988-03-01T23:59:59.000Z

384

RADIATION DETECTOR  

DOE Patents (OSTI)

A radiation detector of the type is described wherein a condenser is directly connected to the electrodes for the purpose of performing the dual function of a guard ring and to provide capacitance coupling for resetting the detector system.

Wilson, H.N.; Glass, F.M.

1960-05-10T23:59:59.000Z

385

Technology Transfer Summit  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Agenda as of April 9, 2012 Agenda as of April 9, 2012 Technology Transfer Summit April 16, 2012 IMC - Trinity Ballroom 4 8:00 - 8:10 Welcome & Introduction Pete Tseronis, DOE Chief Technology Officer 8:10 - 8:50 Accelerating Transfer Within an Innovation Ecosystem Debra M. Amidon, Founder and Chief Strategist, ENTOVATION International, and Author, The Innovation SuperHighway 8:50 - 9:20 Tech Transfer - Predicaments, Perplexities, and Possible Panaceas Rex Northen, Executive Director, Cleantech Open 9:20 - 9:50 A Systems Approach to Innovation Mike Schwenk, Vice President and Director Technology Deployment and Outreach, Pacific Northwest National Laboratory (PNNL) 9:50 - 10:15 DOE's Online Tech Transfer Ecosystem - aka...Stop Building Moai! Robert Bectel, Senior Policy Advisor / Chief Technology Officer

386

VOLUNTARY LEAVE TRANSFER PROGRAM  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

VOLUNTARY LEAVE TRANSFER PROGRAM VOLUNTARY LEAVE TRANSFER PROGRAM (Eligible employees are listed at the end of this narrative) Under the Voluntary Leave Transfer Program you can apply, based on a medical emergency, to receive annual leave donated by other employees. A medical emergency is generally defined as a medical condition of the employee or family member that is likely to keep you (the employee) away from work and cause a loss of pay of at least 24 hours. You are required to submit an Office of Personnel Management (OPM) Form 630, Application to Become A Leave Recipient Under the Voluntary Leave Transfer Program, through your supervisor to be considered for the program. The application must include an explanation of the reason the donation is needed (including a brief description of the

387

Technology Transfer: Success Stories  

NLE Websites -- All DOE Office Websites (Extended Search)

Lawrence Berkeley National Laboratory masthead A-Z Index Berkeley Lab masthead U.S. Department of Energy logo Phone Book Jobs Search Tech Transfer Tech Index For Industry For...

388

Multiscale photosynthetic exciton transfer  

E-Print Network (OSTI)

Photosynthetic light harvesting provides a natural blueprint for bioengineered and biomimetic solar energy and light detection technologies. Recent evidence suggests some individual light harvesting protein complexes (LHCs) and LHC subunits efficiently transfer excitons towards chemical reaction centers (RCs) via an interplay between excitonic quantum coherence, resonant protein vibrations, and thermal decoherence. The role of coherence in vivo is unclear however, where excitons are transferred through multi-LHC/RC aggregates over distances typically large compared with intra-LHC scales. Here we assess the possibility of long-range coherent transfer in a simple chromophore network with disordered site and transfer coupling energies. Through renormalization we find that, surprisingly, decoherence is diminished at larger scales, and long-range coherence is facilitated by chromophoric clustering. Conversely, static disorder in the site energies grows with length scale, forcing localization. Our results suggest s...

Ringsmuth, A K; Stace, T M; 10.1038/nphys2332

2012-01-01T23:59:59.000Z

389

Transfer reactions at ATLAS  

NLE Websites -- All DOE Office Websites (Extended Search)

Transfer reactions before, and with, HELIOS Or - "...seems like an awful lot of work just to do (d,p)..." Congratulations ATLAS Happy 25 th Prologue: Long before ATLAS... 11...

390

Convective heat transfer inside passive solar buildings  

DOE Green Energy (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

391

Entropic corrections to Einstein equations  

SciTech Connect

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

392

Renewal equations for option pricing  

E-Print Network (OSTI)

In this paper we will develop an original approach, based in the use of renewal equations, for obtaining pricing expressions for financial instruments whose underlying asset can be solely described through a simple continuous-time random walk (CTRW). This enhances the potential use of CTRW techniques in finance. We solve these equations for different contract specifications in a particular but exemplifying case. We recover the celebrated results for the Wiener process under certain limits.

Montero, Miquel

2007-01-01T23:59:59.000Z

393

Resonant radiation shed by dispersive shock waves  

E-Print Network (OSTI)

We show that dispersive shock waves resulting from the nonlinearity overbalancing a weak leading-order dispersion can emit resonant radiation owing to higher-order dispersive contributions. We analyze such phenomenon for the defocusing nonlinear Schroedinger equation, giving criteria for calculating the radiated frequency based on the estimate of the shock velocity, revealing also a diversity of possible scenarios depending on the order and magnitude of the dispersive corrections.

Conforti, Matteo; Trillo, Stefano

2013-01-01T23:59:59.000Z

394

Technology Transfer Awards 2012  

Science Conference Proceedings (OSTI)

EPRI's 2012 Technology Transfer Awards recognize the leaders and the innovators who have transferred research into applied results. The 2012 award winners have shown exceptional application of EPRI research and technology to solve a problem of size and significance, to champion a technology both within their companies and across the industry, to drive progress in the electricity sector, and to provide meaningful benefits for stakeholders and for society.

2013-01-23T23:59:59.000Z

395

Multiscale photosynthetic exciton transfer  

E-Print Network (OSTI)

Photosynthetic light harvesting provides a natural blueprint for bioengineered and biomimetic solar energy and light detection technologies. Recent evidence suggests some individual light harvesting protein complexes (LHCs) and LHC subunits efficiently transfer excitons towards chemical reaction centers (RCs) via an interplay between excitonic quantum coherence, resonant protein vibrations, and thermal decoherence. The role of coherence in vivo is unclear however, where excitons are transferred through multi-LHC/RC aggregates over distances typically large compared with intra-LHC scales. Here we assess the possibility of long-range coherent transfer in a simple chromophore network with disordered site and transfer coupling energies. Through renormalization we find that, surprisingly, decoherence is diminished at larger scales, and long-range coherence is facilitated by chromophoric clustering. Conversely, static disorder in the site energies grows with length scale, forcing localization. Our results suggest sustained coherent exciton transfer may be possible over distances large compared with nearest-neighbour (n-n) chromophore separations, at physiological temperatures, in a clustered network with small static disorder. This may support findings suggesting long-range coherence in algal chloroplasts, and provides a framework for engineering large chromophore or quantum dot high-temperature exciton transfer networks.

A. K. Ringsmuth; G. J. Milburn; T. M. Stace

2012-06-14T23:59:59.000Z

396

NREL: Technology Transfer - Ombuds - National Renewable Energy ...  

National Renewable Energy Laboratory Technology Transfer Technology Transfer Ombuds. NREL's Technology Transfer Ombuds offers an informal process to ...

397

ITL Staff Members Receive Tech Transfer Award  

Science Conference Proceedings (OSTI)

ITL Staff Members Receive Tech Transfer Award. ... Regional "Excellence in Technology Transfer" Award for ... the process of transferring a technology ...

2010-10-05T23:59:59.000Z

398

NIST Radiation thermometry  

Science Conference Proceedings (OSTI)

Radiation thermometry. Summary: ... Description: Radiation thermometers are calibrated using a range of variable-temperature blackbodies. ...

2011-10-13T23:59:59.000Z

399

NIST Optical Radiation Group  

Science Conference Proceedings (OSTI)

Optical Radiation Group. Welcome. The Optical Radiation Group maintains, improves, and disseminates the national scales ...

2013-07-29T23:59:59.000Z

400

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

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

Radiative Properties of Cirrus Clouds in the Infrared Region  

Science Conference Proceedings (OSTI)

A multiple-scattering radiative transfer model is employed to evaluate the 11 ?m and the broad-band infrared (IR) fluxes, cooling rates and emittances in model cirrus clouds for a number of standard vertical atmospheric profiles of temperature ...

Graeme L. Stephens

1980-02-01T23:59:59.000Z

402

Measurements and model calculations of radiative fluxes for the...  

NLE Websites -- All DOE Office Websites (Extended Search)

are compared with calculations made with a state-of-the art radiative transfer model (Modtran). The model is driven by measurements that give an as accurate as possible...

403

Jefferson Lab Technology Transfer - JLab  

What is Technology Transfer at Jefferson Lab? The transfer of technology (intellectual property) developed at JLab to the private sector is an important element of ...

404

11th International Conference of Radiation Research  

SciTech Connect

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

405

Local volume-time averaged equations of motion for dispersed, turbulent, multiphase flows  

Science Conference Proceedings (OSTI)

In most flows of liquids and their vapors, the phases are dispersed randomly in both space and time. These dispersed flows can be described only statistically or in terms of averages. Local volume-time averaging is used here to derive a self-consistent set of equations governing momentum and energy transfer in dispersed, turbulent, multiphase flows. The empiricisms required for use with these equations are the subject of current research.

Sha, W.T.; Slattery, J.C.

1980-11-01T23:59:59.000Z

406

String Field Equations from Generalized Sigma Model  

E-Print Network (OSTI)

I I . i LBNL-39854 String Field Equations fromU C B - P T H - 9 7 / 0 3 String F i e l d Equations fromnew approach for deriving the string field equations from a

Bardakci, K.

2010-01-01T23:59:59.000Z

407

Timescape cosmology with radiation fluid  

E-Print Network (OSTI)

The timescape cosmology represents a potentially viable alternative to the standard homogeneous cosmology, without the need for dark energy. Although average cosmic evolution in the timescape scenario only differs substantially from that of Friedmann-Lemaitre model at relatively late epochs when the contribution from the energy density of radiation is negligible, a full solution of the Buchert equations to incorporate radiation is necessary to smoothly match parameters to the epoch of photon decoupling and to obtain constraints from cosmic microwave background data. Here we extend the matter-dominated solution found in earlier work to include radiation, providing series solutions at early times and an efficient numerical integration strategy for generating the complete solution. The numerical solution is used to directly calculate the scale of the sound horizon at decoupling, and at the baryon drag epoch. The constraints on these scales from the Planck satellite data yield bounds on the timescape cosmological...

Duley, James A G; Wiltshire, David L

2013-01-01T23:59:59.000Z

408

Unified Fractional Kinetic Equation and a Fractional Diffusion Equation  

E-Print Network (OSTI)

In earlier papers Saxena et al. (2002, 2003) derived the solutions of a number of fractional kinetic equations in terms of generalized Mittag-Leffler functions which extended the work of Haubold and Mathai (2000). The object of the present paper is to investigate the solution of a unified form of fractional kinetic equation in which the free term contains any integrable function f(t), which provides the unification and extension of the results given earlier recently by Saxena et al. (2002, 2003). The solution has been developed in terms of the Wright function in a closed form by the method of Laplace transform. Further we derive a closed-form solution of a fractional diffusion equation. The asymptotic expansion of the derived solution with respect to the space variable is also discussed. The results obtained are in a form suitable for numerical computation.

R. K. Saxena; A. M. Mathai; H. J. Haubold

2004-06-22T23:59:59.000Z

409

Anomalous Near-Field Heat Transfer between a Cylinder and a Perforated Surface  

E-Print Network (OSTI)

We predict that the near-field radiative heat-transfer rate between a cylinder and a perforated surface depends nonmonotonically on their separation. This anomalous behavior, which arises due to evanescent-wave effects, ...

Rodriguez-Wong, Alejandro

410

An Estimation of the Bulk Transfer Coefficients for a Bare Soil Surface Using a Linear Model  

Science Conference Proceedings (OSTI)

A linear heat budget model is developed to estimate the daytime means of the bulk transfer coefficients for heat and evaporation efficiency using the daily variation of observational data. The daily variation of shortwave radiation, ground-level ...

Dai Matsushima; Junsei Kondo

1995-04-01T23:59:59.000Z

411

W-12: Determination of Interfacial Heat Transfer and Air-gap ...  

Science Conference Proceedings (OSTI)

It is predicted for the Nickel-based alloy when the air-gap is below 0.3mm heat conduction is the dominant heat transfer process; above 0.3mm radiation is the ...

412

The Blackbody Radiation Spectrum Follows from Zero-Point Radiation and the Structure of Relativistic Spacetime in Classical Physics  

E-Print Network (OSTI)

The analysis of this article is entirely within classical physics. Any attempt to describe nature within classical physics requires the presence of Lorentz-invariant classical electromagnetic zero-point radiation so as to account for the Casimir forces between parallel conducting plates at low temperatures. Furthermore, conformal symmetry carries solutions of Maxwell's equations into solutions. In an inertial frame, conformal symmetry leaves zero-point radiation invariant and does not connect it to non-zero-temperature; time-dilating conformal transformations carry the Lorentz-invariant zero-point radiation spectrum into zero-point radiation and carry the thermal radiation spectrum at non-zero temperature into thermal radiation at a different non-zero-temperature. However, in a non-inertial frame, a time-dilating conformal transformation carries classical zero-point radiation into thermal radiation at a finite non-zero-temperature. By taking the no-acceleration limit, one can obtain the Planck radiation spect...

Boyer, Timothy H

2011-01-01T23:59:59.000Z

413

Effect of infrared transparency on the heat transfer through windows: a clarification of the greenhouse effect  

SciTech Connect

The various radiative, convective, and conductive components of the net heat transfer are calculated and illustrated for various infrared transparencies of covers such as would be used in architectural, greenhouse, or solar collector windows. It is shown that in the limiting cases of infrared opacity and infrared transparency the relative contributions of the three modes of heat transfer are altered, but all contribute significantly. The radiation shielding arguments pertain to the analogous greenhouse effect in the atmosphere.

Silverstein, S.D.

1976-07-16T23:59:59.000Z

414

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

415

Radiation receiver  

SciTech Connect

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

416

RADIATION SOURCES  

DOE Patents (OSTI)

A novel long-lived source of gamma radiation especially suitable for calibration purposes is described. The source of gamma radiation is denoted mock iodine131, which comprises a naixture of barium-133 and cesium-137. The barium and cesium are present in a barium-cesium ratio of approximately 5.7/1 to 14/1, uniformly dispersed in an ion exchange resin and a filter surrounding the resin comprised of a material of atomic number below approximately 51, and substantially 0.7 to 0.9 millimeter thick.

Brucer, M.H.

1958-04-15T23:59:59.000Z

417

Parallel Objects and Field Equations  

E-Print Network (OSTI)

This paper considers a generalization of the existing concept of parallel (with respect to a given connection) geometric objects and its possible usage as a suggesting rule in searching for adequate field equations in theoretical physics. The generalization tries to represent mathematically the two-sided nature of the physical objects, the {\\it change} and the {\\it conservation}. The physical objects are presented mathematically by sections $\\Psi$ of vector bundles, the admissible changes $D\\Psi$ are described as a rsult of the action of appropriate differential operators $D$ on these sections, and the conservation propertieis are accounted for by the requirement that suitable projections of $D\\Psi$ on $\\Psi$ and on other appropriate sections must be zero. It is shown that the most important equations of theoretical physics obey this rule. Extended forms of Maxwell and Yang-Mills equations are also considered.

Stoil Donev; Maria Tashkova

2002-05-30T23:59:59.000Z

418

Finite-volume model for chemical vapor infiltration incorporating radiant heat transfer. Interim report  

SciTech Connect

Most finite-volume thermal models account for the diffusion and convection of heat and may include volume heating. However, for certain simulation geometries, a large percentage of heat flux is due to thermal radiation. In this paper a finite-volume computational procedure for the simulation of heat transfer by conduction, convection and radiation in three dimensional complex enclosures is developed. The radiant heat transfer is included as a source term in each volume element which is derived by Monte Carlo ray tracing from all possible radiating and absorbing faces. The importance of radiative heat transfer is illustrated in the modeling of chemical vapor infiltration (CVI) of tubes. The temperature profile through the tube preform matches experimental measurements only when radiation is included. An alternative, empirical approach using an {open_quotes}effective{close_quotes} thermal conductivity for the gas space can match the initial temperature profile but does not match temperature changes that occur during preform densification.

Smith, A.W.; Starr, T.L. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

1995-05-01T23:59:59.000Z

419

NREL: Technology Transfer - Webmaster  

NLE Websites -- All DOE Office Websites (Extended Search)

Webmaster Webmaster To report any problems on or ask a question about the NREL Technology Transfer Web site, you may contact the Webmaster using the online form below. If you have a question or concern that's not related to this Web site, please see our list of contacts for assistance. To contact the Webmaster, please provide your name, e-mail address, and message below. When you are finished, click "Send Message." NOTE: If you enter your e-mail address incorrectly, we will be unable to reply. Your name: Your email address: Your message: Send Message Printable Version Technology Transfer Home About Technology Transfer Technology Partnership Agreements Licensing Agreements Nondisclosure Agreements Research Facilities Commercialization Programs Success Stories News

420

NREL: Technology Transfer - Ombuds  

NLE Websites -- All DOE Office Websites (Extended Search)

Technology Transfer Ombuds Technology Transfer Ombuds NREL's Technology Transfer Ombuds offers an informal process to help resolve issues and concerns regarding the laboratory's technology partnership, patent, and licensing activities. As a designated neutral party, our ombuds provides confidential, resolution-focused services. Through the ombuds process, we encourage collaborative techniques such as mediation to facilitate the speedy and low-cost resolution of complaints and disputes, when appropriate. The NREL Ombuds does not: Handle contract negotiation or other legal issues Act as a decision maker or draw conclusions Investigate or make formal recommendations on findings of fact. The ombuds also does not replace, override, or influence formal review or appeal mechanisms, or serve as an intermediary when legal action is

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

Partnerships and Technology Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Cooperative Research and Development Agreement Cooperative Research and Development Agreement visualization scientist A Cooperative Research and Development Agreement (CRADA) is a mechanism whereby non-federal entities (industry, universities, non-profits, etc.) can collaborate with federal laboratories on research and development projects. CRADAs are specifically technology transfer agreements; technologies developed under CRADAs are expected to be transferred to the private sector for commercial exploitation, either by the non-federal partner or another licensee of such technologies. CRADAs were authorized by the Stevenson-Wydler Technology Innovation Act of 1980 (Public Law 96-480); the authority for government-owned, contractor-operated laboratories such as ORNL to enter into CRADAs was granted by the National Competitiveness Technology Transfer Act of 1989

422

Nonlinear Shear-free Radiative Collapse  

E-Print Network (OSTI)

We study realistic models of relativistic radiating stars undergoing gravitational collapse which have vanishing Weyl tensor components. Previous investigations are generalised by retaining the inherent nonlinearity at the boundary. We transform the boundary condition to an Abel equation of the first kind. A variety of nonlinear solutions are generated all of which can be written explicitly. Several classes of infinite solutions exist.

S. S. Misthry; S. D. Maharaj; P. G. L. Leach

2008-08-15T23:59:59.000Z

423

On An Improvement Of The Planck Radiation Energy Distribution  

E-Print Network (OSTI)

Copyright c?2006 The probability distribution function for thermodynamics and econophysics is obtained by solving an equilibrium equation. This approach is different from the common one of optimizing the entropy of the system or obtaining the state of maximum probability, which usually obtains as a result the Boltzmann distribution. The Gamma distribution is proposed as a better equation to describe the blackbody radiation in substitution of Planck’s radiation equation. Also, a new form of entropy is proposed, that maintains the correct relation with the Clausius ’ formula.

Diego Saá

2006-01-01T23:59:59.000Z

424

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

425

Aspects of forced convective heat transfer in geothermal systems  

DOE Green Energy (OSTI)

A knowledge of convective heat transfer is essential to understanding geothermal systems and other systems of moving groundwater. A simple, kinematic approach toward convective heat transfer is taken here. Concern is not with the cause of the groundwater motion but only with the fact that the water is moving and transferring heat. The mathematical basis of convective heat transfer is the energy equation which is a statement of the first law of thermodynamics. The general solution of this equation for a specific model of groundwater flow has to be done numerically. The numerical algorithm used here employs a finite difference approximation to the energy equation that uses central differences for the heat conduction terms and one-sided differences for the heat convection terms. Gauss--Seidel iteration is then used to solve the finite difference equation at each node of a non-uniform mesh. The Monroe and Red Hill hot springs, a small hydrothermal system in central Utah, provide an example to illustrate the application of convective heat transfer theory to a geophysical problem. Two important conclusions regarding small geothermal systems follow immediately from the results of this application. First, the most rapid temperature rise in the convecting part of a geothermal system is near the surface. Below this initially rapid temperature increase the temperature increases very slowly, and thus temperatures extrapolated from shallow boreholes can be seriously in error. Second, the temperatures and heat flows observed at Monroe and Red Hill, and probably at many other small geothermal areas, can easily result from moderate vertical groundwater velocities in faults and fracture zones in an area of normal heat flow.

Kilty, K.; Chapman, D.S.; Mase, C.

1978-07-01T23:59:59.000Z

426

Technology Transfer: Available Technologies  

NLE Websites -- All DOE Office Websites (Extended Search)

Software and Information Technologies Software and Information Technologies Algorithm for Correcting Detector Nonlinearites Chatelet: More Accurate Modeling for Oil, Gas or Geothermal Well Production Collective Memory Transfers for Multi-Core Processors Energy Efficiency Software EnergyPlus:Energy Simulation Software for Buildings Tools, Guides and Software to Support the Design and Operation of Energy Efficient Buildings Flexible Bandwidth Reservations for Data Transfer Genomic and Proteomic Software LABELIT - Software for Macromolecular Diffraction Data Processing PHENIX - Software for Computational Crystallography Vista/AVID: Visualization and Allignment Software for Comparative Genomics Geophysical Software Accurate Identification, Imaging, and Monitoring of Fluid Saturated Underground Reservoirs

427

Applied heat transfer  

Science Conference Proceedings (OSTI)

Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

Ganapathy, V.

1982-01-01T23:59:59.000Z

428

Technology transfer issue  

Science Conference Proceedings (OSTI)

Testimony by Lawrence J. Brady, Commerce Assistant Secretary for Trade Administration, at Congressional hearings on the national security issues of technology transfers to the Soviet Union identified steps the US needs to take to deal effectively with the problem. These steps include an understanding of how the Soviet Union has and will benefit militarily by acquiring Western technology and efforts to work with other countries, counterintelligence agencies, and industries to stem the flow of technological information. Brady outlined changes in technology development that complicate the enforcement of transfer rules, and emphasized the importance of a close relationship between the business community and the Commerce Department. (DCK)

Jacobson, C.

1982-05-31T23:59:59.000Z

429

Shortwave Radiation Budget of the Southern Hemisphere Using ISCCP C2 and NCEP–NCAR Climatological Data  

Science Conference Proceedings (OSTI)

The seasonal shortwave radiation budget at the surface of the Southern Hemisphere was estimated, for 10° latitudinal zones, using a radiative transfer model with long-term mean monthly climatological data from the International Satellite Cloud ...

N. Hatzianastassiou; I. Vardavas

2001-11-01T23:59:59.000Z

430

HEAT TRANSFER MEANS  

DOE Patents (OSTI)

A heat exchanger is adapted to unifomly cool a spherical surface. Equations for the design of a spherical heat exchanger hav~g tubes with a uniform center-to-center spining are given. The heat exchanger is illustrated in connection with a liquid-fueled reactor.

Fraas, A.P.; Wislicenus, G.F.

1961-07-11T23:59:59.000Z

431

Comments on article 'symmetric heat and mass transfer in a rotating spherical layer,' JETP 94 (3), 459 (2002)  

Science Conference Proceedings (OSTI)

Analytic solutions to the heat and mass transfer equations, which were obtained in [1], are corrected. It is shown that the dependence of the growth rate of the Earth's inner core on heat flux changes in this case.

Alexandrov, D. V., E-mail: Dmitri.Alexandrov@usu.ru; Malygin, A. P. [Ural Federal University (Russian Federation)

2012-02-15T23:59:59.000Z

432

Radiant heat transfer from storage casks to the environment  

SciTech Connect

A spent fuel storage cask must efficiently transfer the heat released by the fuel assemblies through the cask walls to the environment. This heat must be transferred through passive means, limiting the energy transfer mechanisms from the cask to natural convection and radiation heat transfer.. Natural convection is essentially independent of the characteristics of the array of casks, provided there is space between casks to permit a convection loop. Radiation heat transfer, however, depends on the geometric arrangement of the array of casks because the peripheral casks will shadow the interior casks and restrict radiant heat transfer from all casks to the environment. The shadowing of one cask by its neighbors is determined by a view factor that represents the fraction of radiant energy that leaves the surface of a cask and reaches the environment. This paper addresses the evaluation of the view factor between a centrally located spent fuel storage cask and the environment. By combining analytic expressions for the view factor of (1) infinitely long cylinders and (2) finite cylinders with a length-to-diameter ratio of 2 to represent spent fuel storage casks, the view factor can be evaluated for any practical array of spent fuel storage casks.

Carlson, R W; Hovingh, J; Thomas, G R

1999-05-10T23:59:59.000Z

433

Calculating thermal radiation fields from 3D flame reconstruction  

Science Conference Proceedings (OSTI)

Designing fire safety into a building requires a designer to think through issues that include fire ignition, growth and spread. Radiative heat transfer from flames is the dominant method of spread. It is, therefore, necessary to determine the thermal ... Keywords: configuration factor, flame geometry, heat flux, radial basis function, thermal radiation field

Paul Mason; Chris Rogers

2003-02-01T23:59:59.000Z

434

Radiation Protection Act (Pennsylvania)  

Energy.gov (U.S. Department of Energy (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...

435

Radiation Tolerant Metallic Multilayers  

Science Conference Proceedings (OSTI)

Strategies that can alleviate radiation damage may assist the design of radiation tolerant materials. We will summarize our recent studies on radiation damage in ...

436

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

437

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

438

Monte Carlo Methods and Partial Differential Equations ...  

Science Conference Proceedings (OSTI)

... Up, Monte Carlo Methods and Partial Differential Equations: Algorithms and Implications for High-Performance Computing. ...

2013-08-16T23:59:59.000Z

439

Continuous Emission of A Radiation Quantum  

E-Print Network (OSTI)

It is in accordance with such experiments as single photon self-interference that a photon, conveying one radiation energy quantum "$ h \\times$ frequency", is spatially extensive and stretches an electromagnetic wave train. A wave train, hence an energy quantum, can only be emitted by its source gradually. In both the two processes the wave and "particle" attributes of the radiation field are simultaneously prominent, where an overall satisfactory theory has been lacking. This paper presents a first principles treatment, in a unified framework of the classical and quantum mechanics, of the latter process, the emission of a single radiation quantum based on the dynamics of the radiation-emitting source, a charged oscillator which is itself extensive across its confining potential well. During the emission of one single radiation quantum, the extensive charged oscillator undergoes a continuous radiation damping and is non-stationary. This process is in this work treated using a quasi stationary approach, whereby the classical equation of motion, which directly facilitates the correspondence principle for a particle oscillator, and the quantum wave equation are established for each sufficiently brief time interval. As an inevitable consequence of the division of the total time for emitting one single quantum, a fractional Planck constant $h$ is introduced. The solutions to the two simultaneous equations yield for the charged oscillator a continuously exponentially decaying Hamiltonian that is at the same time quantised with respect to the fractional-$h$ at any instant of time; and the radiation wave field emitted over time stretches a wave train of finite length. The total system of the source and radiation field maintains at any time (integer $n$ times) one whole energy quantum, $h \\times$ frequency, in complete accordance with the notion of quantum mechanics and experiment.

J. X. Zheng-Johansson

2013-11-29T23:59:59.000Z

440

SRNL - Technology Transfer - Ombudsman  

NLE Websites -- All DOE Office Websites (Extended Search)

Ombudsman Ombudsman Ombudsman Program Policy The Department of Energy and its management and operating contractors (M & O Contractors) engaging in technology partnership activities, share a mutual objective to ensure complete fairness in the transfer of federally funded technologies into the marketplace for the benefit of the U.S. economy. This includes an interest in open lines of communication and the early identification of issues, complaints and disputes between contractors and their existing or potential partners. The Technology Transfer Ombudsman Program provides an independent point of contact for concerns about technology transfer i SRS Sign ssues, complaints and disputes. The mission of the Ombudsman Program is to elevate to the appropriate SRNS officials the information needed to identify and resolve problems thereby improving satisfaction with SRNS practices and reducing the occasion for formal disputes and litigation. The Ombudsman will not be involved in the merits of cases that are the subject of ongoing dispute resolution or litigation, or investigation incidents thereto. The Ombudsman is not established to be a super-administrator, re-doing what specialized officials have already done. Rather, the Ombudsman is to ensure that appropriate SRNS officials consider all pertinent information when deciding the company's position on a technology transfer complaint. To request forms or acquire additional information contact: Michael Wamstad, 803-725-3751 or mike.wamstad@srs.gov.

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

Low Dose Radiation Research Program: Research Institutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Institutions Institutions Lovelace Respiratory Research Institute Biological Bases for Radiation Adaptive Responses in the Lung-Lovelace Respiratory Research Institute, Albuquerque, NM USA Contact: Dr. Bobby R. Scott Program Objective Our research focuses on elucidating the biological bases for radiation adaptive responses in the lung and for suppressing lung cancer, and to use the knowledge gained to produce an improved systems-biology-based, risk model for lung cancer induction by low-dose, low linear-energy-transfer (LET) radiation. Research was initiated in October 2009. This research should help foster a new era of low-dose radiation risk/benefit assessment. It will have important implications for possible use of low-dose diagnostic radiation (e.g., X-rays) in cancer therapy. It

442

Journal of Quantitative Spectroscopy & Radiative Transfer 109 (2008) 13351337  

E-Print Network (OSTI)

, Antalya in 2001 [10], and Istanbul in 2004 [11]. RAD-V was organized by M. Pinar Mengu¨ c- and Nevin Selc, Adelphi, MD, USA M. Pinar Mengu¨ c-, University of Kentucky, Lexington, KY, USA Organizing committee Jay, Astronomical Institute ``Anton Pannekoek'', University of Amsterdam, The Netherlands Hal Maring, NASA HQ

443

Radiative Transfer through Media with Uncertain or Variable Parameters  

Science Conference Proceedings (OSTI)

While it is now possible to compute the optical transmission, reflection and absorption of a homogeneous horizontal layer of known parameters to great accuracy, the input parameters (optical depth, scattering phase function and single-scattering ...

Keith Ronnholm; M. B. Baker; Halstead Harrison

1980-06-01T23:59:59.000Z

444

Journal of Quantitative Spectroscopy & Radiative Transfer 73 (2002) 583602  

E-Print Network (OSTI)

Engenharia Mec^anica, Universidade Federal do Rio Grande do Sul, 90050-170 Porto Alegre, RS, Brazil c

Siewert, Charles E.

445

Parameterization of Atmospheric Radiative Transfer. Part II: Selection Rules  

Science Conference Proceedings (OSTI)

This paper describes simple, computationally efficient methods of calculating 2-stream broadband fluxes and heating rates in the shortwave and longwave for multilayered media. The method, herein referred to as selection rules, is used in ...

Philip M. Gabriel; Philip T. Partain; Graeme L. Stephens

2001-11-01T23:59:59.000Z

446

Solar Radiative Transfer in Clouds with Vertical Internal Inhomogeneity  

Science Conference Proceedings (OSTI)

To investigate the photon transport in inhomogeneous clouds, a Monte Carlo cloud model with internal variation of optical properties is developed. The data for cloud vertical internal inhomogeneity are chosen from published observations. ...

J. Li; D. J. W. Geldart; Petr Chýlek

1994-09-01T23:59:59.000Z

447

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network (OSTI)

V.I. Glebov, “Hydrogen storage in capillary arrays”, EnergyHydrogen Storage in Microspheres - Final Report”, EnergyHydrogen Production and Storage - R&D Priorities and Gaps”, International Energy

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

448

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

449

Radiative transfer and thermal performance levels in foam insulation boardstocks  

E-Print Network (OSTI)

The validity of predictive models for the thermal conductivity of foam insulation is established based on the fundamental geometry of the closed-cell foam. The extinction coefficient is experimentally and theoretically ...

Moreno, John David

1991-01-01T23:59:59.000Z

450

Radiation properties of cavity Cerenkov radiation  

SciTech Connect

Cerenkov radiation from cavities has been analyzed by quantum electrodynamic theory. Analytical expressions of basic radiation properties such as the Einstein's A and B coefficients are derived and shown to be directly modified by the cavities. The analysis leads to the conclusion that the coherent radiation from the Cerenkov radiation devices is due to super radiance of spontaneous emission instead of stimulated emission. Coherent and incoherent radiations are analyzed in the THz radiation range.

Gao Ju; Shen Fang [Electrical and Computer Engineering Department, University of Illinois, Urbana, Illinois 61801 (United States)

2006-04-15T23:59:59.000Z

451

Sensitivity of aerosol radiative forcing calculations to spectral resolution  

DOE Green Energy (OSTI)

Potential impacts of aerosol radiative forcing on climate have generated considerable recent interest. An important consideration in estimating the forcing from various aerosol components is the spectral resolution used for the solar radiative transfer calculations. This paper examines the spectral resolution required from the viewpoint of overlapping spectrally varying aerosol properties with other cross sections. A diagnostic is developed for comparing different band choices, and the impact of these choices on the radiative forcing calculated for typical sulfate and biomass aerosols was investigated.

Grant, K.E.

1996-10-01T23:59:59.000Z

452

FACILITY SURVEY & TRANSFER Facility Survey & Transfer Overview  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

SURVEY & TRANSFER SURVEY & TRANSFER Facility Survey & Transfer Overview Transfer Activities Checklist Pre-Survey Information Request Survey Report Content Detailed Walkdown Checklist Walkdown Checklist Clipboard Aids S & M Checklist Survey Report Example - Hot Storage Garden Survey Report Example - Tritium System Test Assembly Survey Report Example - Calutron Overview 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. Requirements and guidance for such transfers are contained in:  DOE Order 430.1B Chg. 2, REAL PROPERTY & ASSET MANAGEMENT  DOE Guide 430.1-5, TRANSITION IMPLEMENTATION GUIDE The transfer process is illustrated in the Transfer Process figure. The purpose here is to provide examples of methods and

453

Brookhaven National Laboratory technology transfer report, fiscal year 1986  

SciTech Connect

An increase in the activities of the Office of Research and Technology Applications (ORTA) is reported. Most of the additional effort has been directed to the regional electric utility initiative, but intensive efforts have been applied to the commercialization of a compact synchrotron storage ring for x-ray lithography applications. At least six laboratory technologies are reported as having been transferred or being in the process of transfer. Laboratory accelerator technology is being applied to study radiation effects, and reactor technology is being applied for designing space reactors. Technologies being transferred and emerging technologies are described. The role of the ORTA and the technology transfer process are briefly described, and application assessment records are given for a number of technologies. A mini-incubator facility is also described. (LEW)

Not Available

1986-01-01T23:59:59.000Z

454

Experimental study of natural convective heat transfer in a vertical hexagonal sub channel  

Science Conference Proceedings (OSTI)

The development of new practices in nuclear reactor safety aspects and optimization of recent nuclear reactors, including the APWR and the PHWR reactors, needs a knowledge on natural convective heat transfer within sub-channels formed among several nuclear fuel rods or heat exchanger tubes. Unfortunately, the currently available empirical correlation equations for such heat transfer modes are limited and researches on convective heat transfer within a bundle of vertical cylinders (especially within the natural convection modes) are scarcely done. Although boundary layers around the heat exchanger cylinders or fuel rods may be dominated by their entry regions, most of available convection correlation equations are for fully developed boundary layers. Recently, an experimental study on natural convective heat transfer in a subchannel formed by several heated parallel cylinders that arranged in a hexagonal configuration has been being done. The study seeks for a new convection correlation for the natural convective heat transfer in the sub-channel formed among the hexagonal vertical cylinders. A new convective heat transfer correlation equation has been obtained from the study and compared to several similar equations in literatures.

Tandian, Nathanael P.; Umar, Efrizon; Hardianto, Toto; Febriyanto, Catur [Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesa 10, Bandung 40132 (Indonesia); Nuclear Technology Center for Materials and Radiometry, National Nuclear Energy Agency, Bandung (Indonesia); Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesa 10, Bandung 40132 (Indonesia); Nuclear Energy Regulation Agency, Jakarta (Indonesia)

2012-06-06T23:59:59.000Z

455

Types of Radiation Exposure  

NLE Websites -- All DOE Office Websites (Extended Search)

External Irradiation Contamination Incorporation Biological Effects of Acute, Total Body Irradiation Managing Radiation Emergencies Procedure Demonstration Types of radiation...

456

Radiation Effects In Ceramics  

Science Conference Proceedings (OSTI)

RADIATION MATERIALS SCIENCE IN TECHNOLOGY APPLICATIONS II: Radiation Effects in Ceramics. Sponsored by: Jt. SMD/MSD Nuclear Materials ...

457

Ionizing Radiation Dosimetry  

Science Conference Proceedings (OSTI)

Ionizing Radiation Dosimetry. ... OH. US Air Force Radiation Dosimetry Laboratory, Wright-Patterson - Base, OH [100548- 0] PA. ...

2013-09-06T23:59:59.000Z

458

Radiation Physics Division  

Science Conference Proceedings (OSTI)

... The Radiation Physics Division, part of the Physical Measurement Laboratory ... the measurement standards for ionizing radiations and radioactivity ...

2013-09-05T23:59:59.000Z

459

Technology Transfer: Site Map  

NLE Websites -- All DOE Office Websites (Extended Search)

Site Map Site Map About Us About Technology Transfer Contact Us Available Technologies Advanced Materials Biofuels Biotechnology and Medicine Developing World Energy Environmental Technologies Imaging and Lasers Ion Sources and Beam Technologies Nanotechnology and Microtechnology Software and Information Technology For Industry Licensing Overview Frequently Asked Questions Partnering with Berkeley Lab Licensing Interest Form Receive New Tech Alerts For Researchers What You Need to Know and Do The Tech Transfer Process Forms Record of Invention (Word doc -- please do not use earlier PDF version of the form) Software Disclosure and Abstract (PDF, use Adobe Acrobat or Adobe Reader 9 and up ONLY to complete the form) Policies Conflict of Interest Outside Empolyment Export Control FAQs for Researchers

460

Technology Transfer Reports  

NLE Websites -- All DOE Office Websites (Extended Search)

Advanced Research Projects Agency-Energy (ARPA-E) Advanced Research Projects Agency-Energy (ARPA-E) Oil & Gas Technology Transfer Initiatives USEFUL LINKS Association of University Technology Managers (AUTM) Federal Laboratory Consortium (FLC) FLC Technology Locator Feedback Contact us about Tech Transfer: Mary.McManmon@science.doe.gov Mary McManmon, 202-586-3509 link to Adobe PDF Reader link to Adobe Flash player Reports Navigate Home About Us Contact Information Hide Thumbs First Previous Pause Next Last Set Speed Slideshow speed: 5 seconds Move Autoinduction system New Image Set Autoinduction Autoinduction System The award winning Overnight Express(tm) Autoinduction System developed at BNL simplifies protein production in the widely used T7 gene expression system. Decontamination Foam-based decontamination

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

NREL: Technology Transfer - Events  

NLE Websites -- All DOE Office Websites (Extended Search)

Events Events February 2014 NASEO Energy Outlook Conference February 4 - 7, 2014 Washington , DC Add to calendar Printable Version Technology Transfer Home About Technology Transfer Technology Partnership Agreements Licensing Agreements Nondisclosure Agreements Research Facilities Commercialization Programs Success Stories News Contacts Did you find what you needed? Yes 1 No 0 Thank you for your feedback. Would you like to take a moment to tell us how we can improve this page? Submit We value your feedback. Thanks! We've received your feedback. Something went wrong. Please try again later. NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. NREL U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Alliance for Sustainable Energy, LLC

462

Efficient Data Transfer Protocols  

NLE Websites -- All DOE Office Websites (Extended Search)

Efficient Efficient Data Transfer Protocols for Big Data Brian Tierney ∗ , Ezra Kissel † , Martin Swany † , Eric Pouyoul ∗ ∗ Lawrence Berkeley National Laboratory, Berkeley, CA 94270 † School of Informatics and Computing, Indiana University, Bloomington, IN 47405 Abstract-Data set sizes are growing exponentially, so it is important to use data movement protocols that are the most efficient available. Most data movement tools today rely on TCP over sockets, which limits flows to around 20Gbps on today's hardware. RDMA over Converged Ethernet (RoCE) is a promising new technology for high-performance network data movement with minimal CPU impact over circuit-based infrastructures. We compare the performance of TCP, UDP, UDT, and RoCE over high latency 10Gbps and 40Gbps network paths, and show that RoCE-based data transfers can fill a 40Gbps path using much less CPU than other protocols.

463

Fractional reaction-diffusion equations  

E-Print Network (OSTI)

In a series of papers, Saxena, Mathai, and Haubold (2002, 2004a, 2004b) derived solutions of a number of fractional kinetic equations in terms of generalized Mittag-Leffler functions which provide the extension of the work of Haubold and Mathai (1995, 2000). The subject of the present paper is to investigate the solution of a fractional reaction-diffusion equation. The results derived are of general nature and include the results reported earlier by many authors, notably by Jespersen, Metzler, and Fogedby (1999) for anomalous diffusion and del-Castillo-Negrete, Carreras, and Lynch (2003) for reaction-diffusion systems with L\\'evy flights. The solution has been developed in terms of the H-function in a compact form with the help of Laplace and Fourier transforms. Most of the results obtained are in a form suitable for numerical computation.

R. K. Saxena; A. M. Mathai; H. J. Haubold

2006-04-21T23:59:59.000Z

464

Advanced Technology and Knowledge Transfer  

Science Conference Proceedings (OSTI)

This paper reports on a specific food and agribusiness industry project, employing new technological capabilities to better transfer expert knowledge. Knowledge transfer and technical support are key components of this project. VisIT, which stands for ...

Geetanjali Tandon; Steven T. Sonka

2003-01-01T23:59:59.000Z

465

NREL: Technology Transfer - Licensing Agreements  

National Renewable Energy Laboratory Technology Transfer Licensing Agreements. Through licensing agreements, NREL provides industry with an opportunity to ...

466

Heat Transfer Fluids Containing Nanoparticles  

commercial and industrial heat-transfer applications. ... Refrigeration and other cooling systems Nuclear reactors Aerospace Defense Grinding and ...

467

Argonne TDC: Material Transfer Agreements  

Material Transfer Agreements. Materials produced by researchers at Argonne National Laboratory are often of interest to the private sector.

468

LANL | Partnering | Material Transfer Agreement  

Contacts Event Calendar Maps Organization Phonebook Policy Center Emergency. NEWS. LIBRARY. JOBS. Technology Transfer, TT . Division Home; About Us; ...

469

Green Functions of Relativistic Field Equations  

E-Print Network (OSTI)

In this paper, we restudy the Green function expressions of field equations. We derive the explicit form of the Green functions for the Klein-Gordon equation and Dirac equation, and then estimate the decay rate of the solution to the linear equations. The main motivation of this paper is to show that: (1). The formal solutions of field equations expressed by Green function can be elevated as a postulate for unified field theory. (2). The inescapable decay of the solution of linear equations implies that the whole theory of the matter world should include nonlinear interaction.

Ying-Qiu Gu

2006-12-20T23:59:59.000Z

470

Electromagnetic Nature of Thermo-Mechanical Mass-Energy Transfer Due to Photon Diffusive Re-Emission and  

E-Print Network (OSTI)

mass-transfer trough material systems involved, from a mass-energy source to a sink system. Otherwise- contact" diffusive re-emission and propagation) and commensurate mass-transfer trough material systems conduction theory (parabolic difference equation), allowing infinite speed of thermal energy propagation (i

Kostic, Milivoje M.

471

Synchrotron Ultraviolet Radiation Facility SURF III ...  

Science Conference Proceedings (OSTI)

... Synchrotron Radiation. What is Synchrotron Radiation? Synchrotron radiation ... known. Properties of Synchrotron Radiation. Schwinger ...

472

From Baking a Cake to Solving the Schrodinger Equation  

E-Print Network (OSTI)

The primary emphasis of this study has been to explain how modifying a cake recipe by changing either the dimensions of the cake or the amount of cake batter alters the baking time. Restricting our consideration to the genoise, one of the basic cakes of classic French cuisine, we have obtained a semi-empirical formula for its baking time as a function of oven temperature, initial temperature of the cake batter, and dimensions of the unbaked cake. The formula, which is based on the Diffusion equation, has three adjustable parameters whose values are estimated from data obtained by baking genoises in cylindrical pans of various diameters. The resulting formula for the baking time exhibits the scaling behavior typical of diffusion processes, i.e. the baking time is proportional to the (characteristic length scale)^2 of the cake. It also takes account of evaporation of moisture at the top surface of the cake, which appears to be a dominant factor affecting the baking time of a cake. In solving this problem we have obtained solutions of the Diffusion equation which are interpreted naturally and straightforwardly in the context of heat transfer; however, when interpreted in the context of the Schrodinger equation, they are somewhat peculiar. The solutions describe a system whose mass assumes different values in two different regions of space. Furthermore, the solutions exhibit characteristics similar to the evanescent modes associated with light waves propagating in a wave guide. When we consider the Schrodinger equation as a non-relativistic limit of the Klein-Gordon equation so that it includes a mass term, these are no longer solutions.

Edward A. Olszewski

2005-03-28T23:59:59.000Z

473

Decal transfer lithography  

DOE Patents (OSTI)

A method of making a microstructure includes selectively activating a portion of a surface of a silicon-containing elastomer, contacting the activated portion with a substance, and bonding the activated portion and the substance, such that the activated portion of the surface and the substance in contact with the activated portion are irreversibly attached. The selective activation may be accomplished by positioning a mask on the surface of the silicon-containing elastomer, and irradiating the exposed portion with UV radiation.

Nuzzo, Ralph G. (Champaign, IL); Childs, William R. (Champaign, IL); Motala, Michael J. (Champaign, IL); Lee, Keon Jae (Savoy, IL)

2010-02-16T23:59:59.000Z

474

Technology Transfer Reporting Form | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Technology Transfer Reporting Form Technology Transfer Reporting Form Technology Transfer Reporting Form More Documents & Publications DOE F 3230.6A Technology Partnership...

475

Tech Transfer Summit Agenda | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Tech Transfer Summit Agenda Tech Transfer Summit Agenda Tech Transfer Technology Summit Agenda 4.9.12.pdf More Documents & Publications Risk Management II Summit Agenda Special...

476

Simple Waves in Ideal Radiation Hydrodynamics  

E-Print Network (OSTI)

In the dynamic diffusion limit of radiation hydrodynamics, advection dominates diffusion; the latter primarily affects small scales and has negligible impact on the large scale flow. The radiation can thus be accurately regarded as an ideal fluid, i.e., radiative diffusion can be neglected along with other forms of dissipation. This viewpoint is applied here to an analysis of simple waves in an ideal radiating fluid. It is shown that much of the hydrodynamic analysis carries over by simply replacing the material sound speed, pressure and index with the values appropriate for a radiating fluid. A complete analysis is performed for a centered rarefaction wave, and expressions are provided for the Riemann invariants and characteristic curves of the one-dimensional system of equations. The analytical solution is checked for consistency against a finite difference numerical integration, and the validity of neglecting the diffusion operator is demonstrated. An interesting physical result is that for a material component with a large number of internal degrees of freedom and an internal energy greater than that of the radiation, the sound speed increases as the fluid is rarefied. These solutions are an excellent test for radiation hydrodynamic codes operating in the dynamic diffusion regime. The general approach may be useful in the development of Godunov numerical schemes for radiation hydrodynamics.

Bryan M. Johnson

2008-11-24T23:59:59.000Z

477

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

478

Parabolic equations without a minimum principle  

E-Print Network (OSTI)

In this thesis, we consider several parabolic equations for which the minimum principle fails. We first consider a two-point boundary value problem for a one dimensional diffusion equation. We show the uniqueness and ...

Pang, Huadong

2007-01-01T23:59:59.000Z

479

Moisture Tendency Equations in a Tropical Atmosphere  

Science Conference Proceedings (OSTI)

Direct diagnostic evaluation of the moisture tendency in the moisture equation is very difficult in practice because two poorly measured terms, moisture convergence and precipitation, dominate the equation. Using the near constancy in space and ...

C. López Carrillo; D. J. Raymond

2005-05-01T23:59:59.000Z

480

Vorticity Equation Terms for Extratropical Cyclones  

Science Conference Proceedings (OSTI)

All terms of the frictionless, nonlinear, vorticity equation are examined. Traditional scale analysis provides one of several justifications for using the quasigeostrophic (QG) system of equations to model extratropical cyclones. Analysts of ...

Richard Grotjahn

1996-12-01T23:59:59.000Z

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.


481

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

482

Feynman Equation in Hamiltonian Quantum Field Theory  

E-Print Network (OSTI)

Functional Schr\\"{o}dinger equations for interacting fields are solved via rigorous non-perturbative Feynman type integrals.

Alexander Dynin

2000-05-26T23:59:59.000Z

483

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

484

MODELING OF HEAT TRANSFER IN ROOMS IN THE MODELICA  

NLE Websites -- All DOE Office Websites (Extended Search)

MODELING MODELING OF HEAT TRANSFER IN ROOMS IN THE MODELICA "BUILDINGS" LIBRARY Michael Wetter, Wangda Zuo, Thierry Stephane Nouidui Simulation Research Group, Building Technologies Department Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA ABSTRACT This paper describes the implementation of the room heat transfer model in the free open-source Modelica "Buildings" library. The model can be used as a single room or to compose a multizone building model. We discuss how the model is de- composed into submodels for the individual heat transfer phenomena. We also discuss the main physical assumptions. The room model can be parameterized to use di↵erent modeling assump- tions, leading to linear or non-linear di↵erential algebraic systems of equations. We present nu- merical experiments that show

485

HIGEE Mass Transfer  

E-Print Network (OSTI)

Distillation, absorption, and gas stripping have traditionally been performed in tall columns utilizing trays or packing. Columns perform satisfactorily, but have characteristics which may be disadvantages in some applications: Large size, particularly height; high weight; high cost of installation; difficulty in modularization; foaming for certain systems; must be vertical, especially for trayed towers; large liquid inventory; difficulty in modifying column internals once installed; start up time to reach steady state conditions in excessive. Many of these disadvantages can be overcome by use of HIGEE, an innovative vapor-liquid mass transfer system which utilizes a rotating bed of packing to achieve high efficiency separations, and consequent reduction in size and weight.

Mohr, R. J.; Fowler, R.

1986-06-01T23:59:59.000Z

486

Manipulator mounted transfer platform  

DOE Patents (OSTI)

This invention is comprised of a transfer platform for the conveyance of objects by a manipulator includes a bed frame and saddle clamp secured along an edge of the bed fame and adapted so as to secure the bed frame to a horizontal crosspiece of the manipulator. The platform may thus move with the manipulator in a reciprocal linear path defined by a guide rail. A bed insert may be provided for the support of conveyed objects and a lifting bail may be provided to permit the manipulator arm to install the bed frame upon the crosspiece under remote control. 5 figs.

Dobbins, J.C.; Hoover, M.A.; May, K.W.; Ross, M.J.

1988-10-12T23:59:59.000Z

487

Manipulator mounted transfer platform  

Science Conference Proceedings (OSTI)

A transfer platform for the conveyance of objects by a manipulator includes a bed frame and saddle clamp secured along an edge of the bed frame and adapted so as to secure the bed frame to a horizontal crosspiece of the manipulator. The platform may thus move with the manipulator in a reciprocal linear path defined by a guide rail. A bed insert may be provided for the support of conveyed objects and a lifting bail may be provided to permit the manipulator arm to install the bed frame upon the crosspiece under remote control.

Dobbins, James C. (Idaho Falls, ID); Hoover, Mark A. (Idaho Falls, ID); May, Kay W. (Idaho Falls, ID); Ross, Maurice J. (Pocatello, ID)

1990-01-01T23:59:59.000Z

488

Manipulator mounted transfer platform  

Science Conference Proceedings (OSTI)

The patent describes in a manipulator system for use in hazardous environments including a manipulator adapted for reciprocal movement upon a guide device, a transfer platform. It comprises: a bed frame defining a generally horizontal bed projecting outwardly from the manipulator; and frame mounting means securing the bed frame to the manipulator in a generally cantilevered fashion, thereby essentially minimizing the structure necessary to support the platform outwardly of the manipulator while enhancing operator visibility of the platform and the manipulator during use of the manipulator system.

Dobbins, J.C.; Hoover, M.A.; May, K.W.; Ross, M.J.

1990-01-23T23:59:59.000Z

489

Linearized gyro-kinetic equation  

SciTech Connect

An ordering of the linearized Fokker-Planck equation is performed in which gyroradius corrections are retained to lowest order and the radial dependence appropriate for sheared magnetic fields is treated without resorting to a WKB technique. This description is shown to be necessary to obtain the proper radial dependence when the product of the poloidal wavenumber and the gyroradius is large (k rho much greater than 1). A like particle collision operator valid for arbitrary k rho also has been derived. In addition, neoclassical, drift, finite $beta$ (plasma pressure/magnetic pressure), and unperturbed toroidal electric field modifications are treated. (auth)

Catto, P.J.; Tsang, K.T.

1976-01-01T23:59:59.000Z

490

REGULARITY FOR A DOUBLY NONLINEAR PARABOLIC EQUATION  

E-Print Network (OSTI)

REGULARITY FOR A DOUBLY NONLINEAR PARABOLIC EQUATION JUHA KINNUNEN Abstract. This survey focuses on regularity results for certain degenerate doubly nonlinear parabolic equations in the case when the Lebesgue This note focuses on the regularity of nonnegative weak solutions to the doubly nonlinear parabolic equation

Kinnunen, Juha

491

Coupled Parabolic Equations for Wave Propagation  

E-Print Network (OSTI)

Coupled Parabolic Equations for Wave Propagation Kai Huang, Knut Solna and Hongkai Zhao #3; April 30, 2004 Abstract We develop an algorithm using two coupled parabolic equations for numerical simulation of wave propagation over long distances. The coupled parabolic equations are derived from a two

Zhao, Hongkai

492

Coherent Synchrotron Radiation: Theory and Simulations.  

Science Conference Proceedings (OSTI)

The physics of coherent synchrotron radiation (CSR) emitted by ultra-relativistic electron bunches, known since the last century, has become increasingly important with the development of high peak current free electron lasers and shorter bunch lengths in storage rings. Coherent radiation can be described as a low frequency part of the familiar synchrotron radiation in bending magnets. As this part is independent of the electron energy, the fields of different electrons of a short bunch can be in phase and the total power of the radiation will be quadratic with the number of electrons. Naturally the frequency spectrum of the longitudinal electron distribution in a bunch is of the same importance as the overall electron bunch length. The interest in the utilization of high power radiation from the terahertz and far infrared region in the field of chemical, physical and biological processes has led synchrotron radiation facilities to pay more attention to the production of coherent radiation. Several laboratories have proposed the construction of a facility wholly dedicated to terahertz production using the coherent radiation in bending magnets initiated by the longitudinal instabilities in the ring. Existing synchrotron radiation facilities also consider such a possibility among their future plans. There is a beautiful introduction to CSR in the 'ICFA Beam Dynamics Newsletter' N 35 (Editor C. Biscari). In this paper we recall the basic properties of CSR from the theory and what new effects, we can get from the precise simulations of the coherent radiation using numerical solutions of Maxwell's equations. In particular, transverse variation of the particle energy loss in a bunch, discovered in these simulations, explains the slice emittance growth in bending magnets of the bunch compressors and transverse de-coherence in undulators. CSR may play same the role as the effect of quantum fluctuations of synchrotron radiation in damping rings. It can limit the minimum achievable emittance in the synchrotron light sources for short bunches.

Novokhatski, Alexander; /SLAC

2012-03-29T23:59:59.000Z

493

Low Dose Radiation Research Program: Radiation-Induced Nuclear Factor kB  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation-Induced Nuclear Factor kB mediates survival advantage by Radiation-Induced Nuclear Factor kB mediates survival advantage by Telomerase Activation. Authors: Natarajan M.,1 Mohan S.,2 Pandeswara, S.L.,1 and Herman T.S.1 Institutions: Departments of 1Radiation Oncology and 2Pathology, The University of Texas Health Science Center, San Antonio, Texas Activation of NF-kB in response to low doses of ionizing radiation was first shown in our laboratory. Although studies have shown that NF-kB plays an important role in anti-apoptotic function, little has been done to understand the molecular link between the activation of NF-kB and cellular outcome such as enhanced cell survival after low dose low-linear transfer (LET) radiation. Because upregulation of telomerase activity is associated with longevity and allows cells to escape from senescence, we hypothesize

494

Application of Improved Radiation Modeling to General Circulation Models  

SciTech Connect

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

495

Interline transfer CCD camera  

DOE Patents (OSTI)

An interline CCD sensing device for use in a camera system, includes an imaging area sensitive to impinging light, for generating charges corresponding to the intensity of the impinging light. Sixteen independent registers R1 - R16 sequentially receive the interline data from the imaging area, corresponding to the generated charges. Sixteen output amplifiers S1 - S16 and sixteen ports P1 - P16 for sequentially transferring the interline data, one pixel at a time, in order to supply a desired image transfer speed. The imaging area is segmented into sixteen independent imaging segments A1 - A16, each of which corresponds to one register, on output amplifier, and one output port. Each one of the imaging segments A1 - A16 includes an array of rows and columns of pixels. Each pixel includes a photogate area, an interline CCD channel area, and an anti-blooming area. The anti-blooming area is, in turn, divided into an anti-blooming barrier and an anti-blooming drain.

Prokop, M.S.; McCurnin, T.W.; Stump, C.J.; Stradling, G.L.

1993-12-31T23:59:59.000Z

496

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

497

Radiation Safety  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Brotherhood of Locomotive Brotherhood of Locomotive Engineers & Trainmen Scott Palmer BLET Radiation Safety Officer New Hire Training New Hire study topics * GCOR * ABTH * SSI * Employee Safety * HazMat * Railroad terminology * OJT * 15-week class * Final test Hazardous Materials * Initial new-hire training * Required by OSHA * No specified class length * Open book test * Triennial module Locomotive Engineer Training A little bit older...a little bit wiser... * Typically 2-4 years' seniority * Pass-or-get-fired promotion * Intensive program * Perpetually tested to a higher standard * 20 Weeks of training * 15 of that is OJT * General Code of Operating Rules * Air Brake & Train Handling * System Special Instructions * Safety Instructions * Federal Regulations * Locomotive Simulators * Test Ride * Pass test with 90% Engineer Recertification

498

RADIATION COUNTER  

DOE Patents (OSTI)

This patent relates to a radiation counter, and more particularly, to a scintillation counter having high uniform sensitivity over a wide area and capable of measuring alpha, beta, and gamma contamination over wide energy ranges, for use in quickly checking the contami-nation of personnel. Several photomultiplier tubes are disposed in parallel relationship with a light tight housing behind a wall of scintillation material. Mounted within the housing with the photomultipliers are circuit means for producing an audible sound for each pulse detected, and a range selector developing a voltage proportional to the repetition rate of the detected pulses and automatically altering its time constant when the voltage reaches a predetermined value, so that manual range adjustment of associated metering means is not required.

Goldsworthy, W.W.

1958-02-01T23:59:59.000Z

499