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arXiv · 2404.18039

Implicit Update of the Moment Equations for a Multi-Species, Homogeneous BGK Model

Evan Habbershaw·Cory D. Hauck·Steven M. Wise
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Abstract

A simple iterative approach for solving a set of implicit kinetic moment equations is proposed. This implicit solve is a key component in the IMEX discretization of the multi-species Bhatnagar-Gross-Krook (M-BGK) model with nontrivial collision frequencies depending on individual species temperatures. We prove that under mild time step restrictions, the iterative method generates a contraction mapping. Numerical simulations are provided to illustrate results of the IMEX scheme using the implicit moment solver.

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Evan Habbershaw, Cory D. Hauck, Steven M. Wise. 2024-04-28. Implicit Update of the Moment Equations for a Multi-Species, Homogeneous BGK Model. https://arxiv.org/abs/2404.18039

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