Transport Theory and Statistical Physics最新文献_第4页

Kinetic Equations for Stark Line Shapes 斯塔克线形的动力学方程

Transport Theory and Statistical Physics Pub Date : 2012-09-14 DOI: 10.1080/00411450.2012.671210

J. Rosato, H. Capes, Y. Marandet, A. Mekkaoui, R. Stamm

引用次数: 3

Quantum Corrections on the Radiative Transfer Equation 辐射传递方程的量子修正

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671211

J. Rosato

引用次数: 5

The Asymptotic Telegrapher’s Equation (P1) Approximation for Time-Dependent, Thermal Radiative Transfer 随时间变化的热辐射传递的渐近电报员方程(P1)近似

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671205

Shay I. Heizler

{"title":"The Asymptotic Telegrapher’s Equation (P1) Approximation for Time-Dependent, Thermal Radiative Transfer","authors":"Shay I. Heizler","doi":"10.1080/00411450.2012.671205","DOIUrl":"https://doi.org/10.1080/00411450.2012.671205","url":null,"abstract":"We develop the asymptotic P 1 approximation for the time-dependent thermal radiative transfer equation for a multidimensional general geometry. Careful derivation of the asymptotic P 1 equations, directly from the time-dependent Boltzmann equation, yields a particle velocity that is closer (v≈0.91c) to the exact value of c but is based on an asymptotic analysis rather than diffusion theory (infinite velocity) or conventional P 1 theory (which gives rise to the Telegrapher’s equation, ). While this approach does not match the exact value of c as does the P 1/3 method, the latter method is an ad hoc approach that has not been justified on theoretical grounds. This article provides the theoretical justification for the almost-correct value of c that yields improved results for the well-known (one-dimensional) Su-Olson benchmark for radiative transfer, for which we obtain a semi-analytic solution in the case of local thermodynamic equilibrium. We found that the asymptotic P 1 approximation yields a better solution than the diffusion, the classic P 1, and the P 1/3 approximations, yielding the correct steady-state behavior for the energy density and the (almost) correct particle velocity.","PeriodicalId":49420,"journal":{"name":"Transport Theory and Statistical Physics","volume":"41 1","pages":"175 - 199"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00411450.2012.671205","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58909219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

A Consistent, Moment-Based, Multiscale Solution Approach for Thermal Radiative Transfer Problems 热辐射传递问题的一致、基于矩的多尺度求解方法

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671224

H. Park, D. Knoll, R. M. Rauenzahn, A. Wollaber, J. Densmore

引用次数: 41

SP 2—Asymptotic P 1 Equivalence SP 2 -渐近p1等价

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.672358

Shay I. Heizler, P. Ravetto

{"title":"SP 2—Asymptotic P 1 Equivalence","authors":"Shay I. Heizler, P. Ravetto","doi":"10.1080/00411450.2012.672358","DOIUrl":"https://doi.org/10.1080/00411450.2012.672358","url":null,"abstract":"This article is devoted to analyzing the physical features of the time-dependent P 2 model in plane geometry and the simplified P 2 (SP 2) model for general geometry. The relationships that can be established with the P 1 model (which gives rise to the telegrapher’s equation) are discussed in detail. In particular, the propagation properties are considered, showing that the signal is characterized by propagation velocity that is times the correct particle velocity. This result is also obtained by direct observation of the equivalent three discrete ordinates equations (S 3) in a slab geometry. In addition, a consistent asymptotic approach is carried out on the SP 2 equations, as can be done in a P 1 formulation. We find that in the diffusion limit, the SP 2 approximation yields the same asymptotic behavior as the asymptotic P 1 approximation that is derived from the exact time-dependent Boltzmann equation. In the absorbing limit, the asymptotic behavior of the SP 2 equations tends to be the exact behavior of SP 2; i.e., with a propagation velocity that is times the particle velocity, which is lower than that for the asymptotic P 1 approximation that tends to the exact particle velocity. These observations are supported by numerical results for a simple problem in a one-dimensional transport problem. The asymptotic P 1 and P 2 approximations are much closer to the exact transport solution than the classic P 1 approximation.","PeriodicalId":49420,"journal":{"name":"Transport Theory and Statistical Physics","volume":"41 1","pages":"304 - 324"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00411450.2012.672358","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58910015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Radiative Transport Reconsidered 重新考虑辐射输运

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671208

N. Corngold

引用次数: 1

On Radiative Transfer in Dense Vegetation Canopies 稠密植被冠层的辐射转移研究

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671218

P. Picca, R. Furfaro, B. Ganapol

{"title":"On Radiative Transfer in Dense Vegetation Canopies","authors":"P. Picca, R. Furfaro, B. Ganapol","doi":"10.1080/00411450.2012.671218","DOIUrl":"https://doi.org/10.1080/00411450.2012.671218","url":null,"abstract":"This article presents a review of the special features exhibited by the transport of photons in dense vegetation canopies. The conservation of photons for particles moving in canopy media yields a linear Boltzmann Equation similar to conventional participating media. However, because of the turbid medium approximation where the atomic leaves are modeled as a gas cloud of infinitesimal plates with specified orientation, the overall system is not rotationally invariant. The latter affects the mathematical nature of the canopy equation and requires special numerical treatment to generate accurate numerical solutions. Here, the most common solution techniques are reviewed with special emphasis on two highly accurate methodologies, namely the Singular Eigenfunction Expansion, which is the basis of the F N method for canopy transport and the Analytical Discrete Ordinate (ADO) method. It is shown that the conventional ADO method can be easily extended to canopy transport problems by taking advantage of special symmetries exhibited by the intercept function and the area scattering function employed to describe the canopy optical properties.","PeriodicalId":49420,"journal":{"name":"Transport Theory and Statistical Physics","volume":"41 1","pages":"223 - 244"},"PeriodicalIF":0.0,"publicationDate":"2012-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00411450.2012.671218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58909829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Remarks on the Speed of Heat Waves 关于热浪速度的评论

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671220

M. Makai

引用次数: 0

Analytic Treatment of Source Photon Emission Times to Reduce Noise in Implicit Monte Carlo Calculations 隐式蒙特卡罗计算中源光子发射时间的解析处理以降低噪声

Transport Theory and Statistical Physics Pub Date : 2012-05-01 DOI: 10.1080/00411450.2012.671221

T. Trahan, N. Gentile

引用次数: 4

Calculation of entropy production in slightly rarefied gas flows by Sonine polynomial expansion 用Sonine多项式展开计算微稀薄气体流动的熵产

Transport Theory and Statistical Physics Pub Date : 2012-01-18 DOI: 10.1080/00411459708221778

Liu Guangjun

引用次数: 0