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arXiv · 1105.2466

CASTRO: A New Compressible Astrophysical Solver. II. Gray Radiation Hydrodynamics

W. Zhang·L. Howell·A. Almgren·A. Burrows·J. Bell
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Abstract

We describe the development of a flux-limited gray radiation solver for the compressible astrophysics code, CASTRO. CASTRO uses an Eulerian grid with block-structured adaptive mesh refinement based on a nested hierarchy of logically-rectangular variable-sized grids with simultaneous refinement in both space and time. The gray radiation solver is based on a mixed-frame 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 source-sink terms. The hyperbolic subsystem is solved explicitly with a high-order Godunov scheme, whereas the parabolic part is solved implicitly with a first-order backward Euler method.

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W. Zhang, L. Howell, A. Almgren, A. Burrows, J. Bell. 2011-05-12. CASTRO: A New Compressible Astrophysical Solver. II. Gray Radiation Hydrodynamics. https://doi.org/10.1088/0067-0049/196/2/20

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