Godunov Methods for Stiff Source Term Conservation Laws and Radiation Hydrodynamics

Michael Sekora, Princeton University

Radiation hydrodynamics is a fluid description of matter (plasma) that absorbs and emits electromagnetic radiation and in so doing modifies dynamical behavior. The coupling between matter and radiation is significant in many phenomena related to astrophysics and plasma physics, where radiation comprises a major fraction of the system’s internal energy and momentum and provides the dominant transport mechanism. This poster focuses on a numerical method that I have been developing for radiation hydrodynamics (i.e., conservation laws with stiff source terms) that is asymptotically preserving and uniformly well behaved from the photon free streaming (hyperbolic) limit through the equilibrium diffusion (parabolic) limit. The method is a modified higher order Godunov scheme that directly couples stiff source term effects to the hyperbolic structure of the system of conservation laws; it is composed of a predictor step that is based on Duhamel’s principle, and a corrector step that is based on Picard iteration.

Abstract Author(s): Michael D Sekora and James M Stone