Numerical Resolution of a Three Temperature Plasma Model

This paper is devoted to the numerical approximation of a three temperature plasma model: one for the ions, one for the electrons and one for the radiation (photons). A reformulation of the model is proposed that allows to build a convex combination-based scheme that unconditionally satisfies a maximum principle, at each sub-iteration of the non-linear iterative process. This yields a very robust scheme that can handle stiff source terms. In addition, the methodology is extended to include the contribution of a radiative flux (Rosseland diffusion approximation) and electronic and ionic conductivities (Spitzer–Härm diffusion approximation). Several numerical results are carried out to demonstrate the interest of the numerical approach.