CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS
Abstract
We describe the development of a fluxlimited gray radiation solver for the compressible astrophysics code, CASTRO. CASTRO uses an Eulerian grid with blockstructured adaptive mesh refinement based on a nested hierarchy of logically rectangular variablesized grids with simultaneous refinement in both space and time. The gray radiation solver is based on a mixedframe formulation of radiation hydrodynamics. In our approach, the system is split into two parts, one part that couples the radiation and fluid in a hyperbolic subsystem, and another parabolic part that evolves radiation diffusion and sourcesink terms. The hyperbolic subsystem is solved explicitly with a highorder Godunov scheme, whereas the parabolic part is solved implicitly with a firstorder backward Euler method.
 Authors:
 Center for Computational Sciences and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)
 Center for Applied Scientific Computing, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)
 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
 Publication Date:
 OSTI Identifier:
 21560316
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 196; Journal Issue: 2; Other Information: DOI: 10.1088/00670049/196/2/20
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; DIFFUSION; HYDRODYNAMICS; RADIANT HEAT TRANSFER; ENERGY TRANSFER; FLUID MECHANICS; HEAT TRANSFER; MECHANICS; PHYSICS
Citation Formats
Zhang, W., Almgren, A., Bell, J., Howell, L., and Burrows, A.. CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS. United States: N. p., 2011.
Web. doi:10.1088/00670049/196/2/20.
Zhang, W., Almgren, A., Bell, J., Howell, L., & Burrows, A.. CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS. United States. doi:10.1088/00670049/196/2/20.
Zhang, W., Almgren, A., Bell, J., Howell, L., and Burrows, A.. 2011.
"CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS". United States.
doi:10.1088/00670049/196/2/20.
@article{osti_21560316,
title = {CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS},
author = {Zhang, W. and Almgren, A. and Bell, J. and Howell, L. and Burrows, A.},
abstractNote = {We describe the development of a fluxlimited gray radiation solver for the compressible astrophysics code, CASTRO. CASTRO uses an Eulerian grid with blockstructured adaptive mesh refinement based on a nested hierarchy of logically rectangular variablesized grids with simultaneous refinement in both space and time. The gray radiation solver is based on a mixedframe formulation of radiation hydrodynamics. In our approach, the system is split into two parts, one part that couples the radiation and fluid in a hyperbolic subsystem, and another parabolic part that evolves radiation diffusion and sourcesink terms. The hyperbolic subsystem is solved explicitly with a highorder Godunov scheme, whereas the parabolic part is solved implicitly with a firstorder backward Euler method.},
doi = {10.1088/00670049/196/2/20},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 196,
place = {United States},
year = 2011,
month =
}

We present a formulation for multigroup radiation hydrodynamics that is correct to order O(v/c) using the comovingframe approach and the fluxlimited diffusion approximation. We describe a numerical algorithm for solving the system, implemented in the compressible astrophysics code, CASTRO. CASTRO uses a Eulerian grid with blockstructured adaptive mesh refinement based on a nested hierarchy of logically rectangular variablesized grids with simultaneous refinement in both space and time. In our multigroup radiation solver, the system is split into three parts: one part that couples the radiation and fluid in a hyperbolic subsystem, another part that advects the radiation in frequency space,more »

CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. I. HYDRODYNAMICS AND SELFGRAVITY
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