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arXiv · 2404.11775

A Nonlinear, Conservative, Entropic Fokker-Planck Model for Multi-Species Collisions

Evan Habbershaw·Cory D. Hauck·Jingwei Hu·Jeffrey R. Haack
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Abstract

A multi-species Fokker-Planck model for simulating particle collisions in a plasma is presented. The model includes various parameters that must be tuned. Under reasonable assumptions on these parameters, the model satisfies appropriate conservation laws, dissipates an entropy, and satisfies an $\mathcal{H}$-Theorem. In addition, the model parameters provide the additional flexibility that is used to match simultaneously momentum and temperature relaxation formulas derived from the Boltzmann collision operator for a binary mixture with Coulomb potentials. A numerical method for solving the resulting space-homogeneous kinetic equation is presented and two examples are provided to demonstrate the relaxation of species bulk velocities and temperatures to their equilibrium values.

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Evan Habbershaw, Cory D. Hauck, Jingwei Hu, Jeffrey R. Haack. 2024-04-17. A Nonlinear, Conservative, Entropic Fokker-Planck Model for Multi-Species Collisions. https://arxiv.org/abs/2404.11775

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