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Related papers: Multi-Group Discontinuous Asymptotic $P_1$ Approxi…

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Based on the path integral representation of the partition function of a many body system with separable two body interaction we propose a systematic extension of the perturbed static path approximation (PSPA) to lower temperatures.…

Statistical Mechanics · Physics 2009-11-07 Christian Rummel , Joachim Ankerhold

We study the paraxial wave equation with a randomly perturbed index of refraction, which can model the propagation of a wave beam in a turbulent medium. The random perturbation is a stationary and isotropic process with a general form of…

Analysis of PDEs · Mathematics 2022-05-10 Liliana Borcea , Josselin Garnier , Knut Solna

An implicit method for radiative transfer in SPH is described. The diffusion approximation is used, and the hydrodynamic calculations are performed by a fully three--dimensional SPH code. Instead of the energy equation of state for an ideal…

Astrophysics · Physics 2009-11-11 Serge Viau , Pierre Bastien , Seung-Hoon Cha

Non-equilibrium radiation diffusion is an important mechanism of energy transport in Inertial Confinement Fusion, astrophysical plasmas, furnaces and heat exchangers. In this paper, an analytical solution to the non-equilibrium Marshak…

Mathematical Physics · Physics 2013-01-17 Karabi Ghosh

In this paper we present two efficient implementations of the diffusion approximation to be employed in Monte Carlo computations of radiative transfer in dusty media of massive circumstellar disks. The aim is to improve the accuracy of the…

Instrumentation and Methods for Astrophysics · Physics 2009-11-13 M. Min , C. P. Dullemond , C. Dominik , A. de Koter , J. W. Hovenier

This paper is concerned with the asymptotic description of high-frequency waves in locally periodic media. A key issue is that the Bloch-dispersion curves vary with the local microstructure, giving rise to hidden singularities associated…

Optics · Physics 2016-12-13 Ory Schnitzer

We present and analyze a high-order discontinuous Galerkin method for the space discretization of the wave propagation model in thermo-poroelastic media. The proposed scheme supports general polytopal grids. Stability analysis and…

Numerical Analysis · Mathematics 2023-06-28 Stefano Bonetti , Michele Botti , Ilario Mazzieri , Paola F. Antonietti

The propagation of focused wave groups in intermediate water depth and the shoaling zone is experimentally and numerically considered in this paper. The experiments are carried out in a two-dimensional wave flume and wave trains derived…

Fluid Dynamics · Physics 2020-02-20 Iskander Abroug , Nizar Abcha , Denys Dutykh , Armelle Jarno , François Marin

This paper presents a new model of North Polar Coronal Hole (NPCH) to study dissipation/propagation of MHD waves. We investigate the effects of the isotropic viscosity and heat conduction on the propagation characteristics of the MHD waves…

Solar and Stellar Astrophysics · Physics 2023-06-28 E. Devlen , D. Zengin Çamurdan , M. Yardımcı , E. R. Pekünlü

Transformation optics originating from the invariance of Maxwell's equations under the coordinate mapping has enabled the design and demonstration of many fascinating electromagnetic devices that were unconceivable or deemed impossible…

Materials Science · Physics 2013-11-25 Yungui Ma , Lu Lan , Wei Jiang , Fei Sun , Sailing He

In this paper, we study large-time asymptotics for heat and fractional heat equations in two discrete settings: the full lattice \(\mathbb Z^d\) and finite connected subgraphs with Dirichlet boundary condition. These results provide a…

Analysis of PDEs · Mathematics 2026-02-19 Rui Chen , Bo Li

A multifield asymptotic homogenization technique for periodic thermo-diffusive elastic materials is provided in the present study. Field equations for the first-order equivalent medium are derived and overall constitutive tensors are…

Fluid Dynamics · Physics 2020-02-27 Francesca Fantoni , Andrea Bacigalupo

The equations of motion in a macroscopically inhomogeneous porous medium saturated by a fluid are derived. As a first verification of the validity of these equations, a two-layer rigid frame porous system considered as one single porous…

Simulations are made of a probe particle diffusing through a complex fluid. Probe particle motions are described by the Mori-Zwanzig equation and Mori's orthogonal hierarchy of random forces scheme, subject to the approximation that the…

Soft Condensed Matter · Physics 2014-06-20 George D. J. Phillies

We study the phenomenon of diffusive radiative heat waves (Marshak waves) under general boundary conditions. In particular, we derive full analytic solutions for the subsonic case, that include both the ablation and the shock wave regions.…

Statistical Mechanics · Physics 2015-08-14 Tomer Shussman , Shay I. Heizler

Radiative heat transfer between uniform plates is bounded by the narrow range and limited contribution of surface waves. Using a combination of analytical calculations and numerical gradient-based optimization, we show that such a…

Mesoscale and Nanoscale Physics · Physics 2017-07-07 Weiliang Jin , Riccardo Messina , Alejandro W. Rodriguez

By applying Rohlin's result on the classification of homomorphisms of Lebesgue space, the random inertial manifold of a stochastic damped nonlinear wave equations with singular perturbation is proved to be approximated almost surely by that…

Analysis of PDEs · Mathematics 2012-09-04 Yan Lv , Wei Wang , Anthony Roberts

The radiative transfer equation (RTE) models the transport of light inside photonic scattering samples such as paint, foam and tissue. Analytic approximations to solve the RTE fail for samples with strong absorption and dominant anisotropic…

Optics · Physics 2022-03-24 Ozan Akdemir , Ad Lagendijk , Willem L. Vos

This work presents efficient solution techniques for radiative transfer in the smoothed particle hydrodynamics discretization. Two choices that impact efficiency are how the material and radiation energy are coupled, which determines the…

Computational Physics · Physics 2021-03-17 Brody R. Bassett , J. Michael Owen , Thomas A. Brunner

Starting from the hydrostatic Boussinesq equations, we derive a time-averaged `hydrostatic wave equation' that describes the propagation of inertia-gravity internal waves through quasi-geostrophic flow. The derivation uses a…

Fluid Dynamics · Physics 2017-10-11 Gregory L. Wagner , Gwenael Ferrando , William R. Young