Asymptotic analysis of fluid models for the coupling of radiation and hydrodynamics

Abstract This work addresses some asymptotic regimes for the coupling of radiation and hydrodynamics, and is inspired by the still non-answered need of high resolution and robust schemes for the numerical solutions of these problems. Using a simple characterization of the isotropy of the scattering in the comobile reference frame, we derive various asymptotic regimes. Among them is the non-equilibrium regime. Then we prove that the method of moments is compatible with the non-equilibrium regime. We also study the Rankine–Hugoniot relations.