A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS
Abstract
We develop a numerical scheme for solving fully special relativistic, resistive radiation magnetohydrodynamics. Our code guarantees conservation of total mass, momentum, and energy. The radiation energy density and the radiation flux are consistently updated using the M1 closure method, which can resolve an anisotropic radiation field, in contrast to the Eddington approximation, as well as the fluxlimited diffusion approximation. For the resistive part, we adopt a simple form of Ohm's law. The advection terms are explicitly solved with an approximate Riemann solver, mainly the HartenLaxvan Leer scheme; the HLLC and HLLD schemes are also solved for some tests. The source terms, which describe the gasradiation interaction and the magnetic energy dissipation, are implicitly integrated, relaxing the CourantFriedrichsLewy condition even in an optically thick regime or a large magnetic Reynolds number regime. Although we need to invert 4 MultiplicationSign 4 matrices (for the gasradiation interaction) and 3 MultiplicationSign 3 matrices (for the magnetic energy dissipation) at each grid point for implicit integration, they are obtained analytically without preventing massive parallel computing. We show that our code gives reasonable outcomes in numerical tests for ideal magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We also applied our resistive code to the relativistic Petschektype magneticmore »
 Authors:
 Center for Computational Astrophysics, National Astronomical Observatory of Japan, Mitaka, Tokyo 1818588 (Japan)
 Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 1818588 (Japan)
 Publication Date:
 OSTI Identifier:
 22121779
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 772; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ADVECTION; ANISOTROPY; APPROXIMATIONS; DIFFUSION; ENERGY DENSITY; ENERGY LOSSES; MAGNETIC RECONNECTION; MAGNETIC REYNOLDS NUMBER; MAGNETOHYDRODYNAMICS; MATRICES; NUMERICAL ANALYSIS; OHM LAW; RADIANT HEAT TRANSFER; RADIATION FLUX; RELATIVISTIC RANGE; SOURCE TERMS
Citation Formats
Takahashi, Hiroyuki R., and Ohsuga, Ken. A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS. United States: N. p., 2013.
Web. doi:10.1088/0004637X/772/2/127.
Takahashi, Hiroyuki R., & Ohsuga, Ken. A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS. United States. doi:10.1088/0004637X/772/2/127.
Takahashi, Hiroyuki R., and Ohsuga, Ken. 2013.
"A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS". United States.
doi:10.1088/0004637X/772/2/127.
@article{osti_22121779,
title = {A NUMERICAL TREATMENT OF ANISOTROPIC RADIATION FIELDS COUPLED WITH RELATIVISTIC RESISTIVE MAGNETOFLUIDS},
author = {Takahashi, Hiroyuki R. and Ohsuga, Ken},
abstractNote = {We develop a numerical scheme for solving fully special relativistic, resistive radiation magnetohydrodynamics. Our code guarantees conservation of total mass, momentum, and energy. The radiation energy density and the radiation flux are consistently updated using the M1 closure method, which can resolve an anisotropic radiation field, in contrast to the Eddington approximation, as well as the fluxlimited diffusion approximation. For the resistive part, we adopt a simple form of Ohm's law. The advection terms are explicitly solved with an approximate Riemann solver, mainly the HartenLaxvan Leer scheme; the HLLC and HLLD schemes are also solved for some tests. The source terms, which describe the gasradiation interaction and the magnetic energy dissipation, are implicitly integrated, relaxing the CourantFriedrichsLewy condition even in an optically thick regime or a large magnetic Reynolds number regime. Although we need to invert 4 MultiplicationSign 4 matrices (for the gasradiation interaction) and 3 MultiplicationSign 3 matrices (for the magnetic energy dissipation) at each grid point for implicit integration, they are obtained analytically without preventing massive parallel computing. We show that our code gives reasonable outcomes in numerical tests for ideal magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We also applied our resistive code to the relativistic Petschektype magnetic reconnection, revealing the reduction of the reconnection rate via radiation drag.},
doi = {10.1088/0004637X/772/2/127},
journal = {Astrophysical Journal},
number = 2,
volume = 772,
place = {United States},
year = 2013,
month = 8
}

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