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arXiv · 2101.09047

A consistent BGK model with velocity-dependent collision frequency for gas mixtures

Jeff Haack·Cory Hauck·Christian Klingenberg·Marlies Pirner·Sandra Warnecke
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Abstract

We derive a multi-species BGK model with velocity-dependent collision frequency for a non-reactive, multi-component gas mixture. The model is derived by minimizing a weighted entropy under the constraint that the number of particles of each species, total momentum, and total energy are conserved. We prove that this minimization problem admits a unique solution for very general collision frequencies. Moreover, we prove that the model satisfies an H-Theorem and characterize the form of equilibrium.

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Jeff Haack, Cory Hauck, Christian Klingenberg, Marlies Pirner, Sandra Warnecke. 2021-01-22. A consistent BGK model with velocity-dependent collision frequency for gas mixtures. https://doi.org/10.1007/s10955-021-02821-2

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