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arXiv · 2409.01827

Radiative hydrodynamic equations with nonequilibrium radiative transfer

Mingyu Quan·Xiaojian Yang·Yufeng Wei·Kun Xu
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Abstract

This paper presents a kinetic model for the coupled evolution of radiation, electrons, and ions in a radiation plasma system. The model is solved using two methods. The gas-kinetic scheme (GKS) for electron and ion hydrodynamics and the unified gas-kinetic scheme (UGKS) for non-equilibrium radiative transfer. The UGKS accurately captures multiscale photon transport from free streaming to diffusion across varying fluid opacities. This approach enables the scheme to model equilibrium plasma with non-equilibrium radiation transport. The model is validated through several test cases, including radiative transfer in kinetic and diffusion regimes, Marshak wave, Radiative shock, 3T(three-temperature) double lax shock tube problem, two-dimensional Sedov blast wave, and two-dimensional tophat based problem. These tests demonstrate the current scheme's capability to handle diverse radiation plasma scenarios.

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Mingyu Quan, Xiaojian Yang, Yufeng Wei, Kun Xu. 2025-01-09. Radiative hydrodynamic equations with nonequilibrium radiative transfer. https://arxiv.org/abs/2409.01827

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