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arXiv · 2306.07945

Stability analysis of an extended quadrature method of moments for kinetic equations

Ruixi Zhang·Qian Huang·Wen-An Yong
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Abstract

This paper performs a stability analysis of a class of moment closure systems derived with an extended quadrature method of moments (EQMOM) for the one-dimensional BGK equation. The class is characterized with a kernel function. A sufficient condition on the kernel is identified for the EQMOM-derived moment systems to be strictly hyperbolic. We also investigate the realizability of the moment method. Moreover, sufficient and necessary conditions are established for the two-node systems to be well-defined and strictly hyperbolic, and to preserve the dissipation property of the kinetic equation.

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Ruixi Zhang, Qian Huang, Wen-An Yong. 2023-06-13. Stability analysis of an extended quadrature method of moments for kinetic equations. https://arxiv.org/abs/2306.07945

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