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arXiv · 1910.10755

Fokker-Planck model for binary mixtures

Samarth Agrawal·S. K. Singh·Santosh Ansumali
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Abstract

In dilute gas kinetic theory, model collision dynamics such as Bhatnagar-Gross-Krook (BGK) model is often used to get a better insight and numerical modelling. BGK model and its variants assume that highly nonlinear collision term can be replaced by a simple relaxation dynamics towards Maxwell-Boltzmann distribution. Lebowitz et al., proposed an alternative framework for the collision model, known as Fokker-Planck model, where the relaxation of an arbitrary distribution towards Maxwell-Boltzmann distribution is modelled as a drift-diffusion process in velocity space. In the present manuscript, we extend the single component Fokker-Planck model to a binary gas mixture model over a large range of Schmidt numbers. We prove that these mixture models satisfy the necessary conservation laws and the H-theorem.

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Samarth Agrawal, S. K. Singh, Santosh Ansumali. 2019-10-23. Fokker-Planck model for binary mixtures. https://doi.org/10.1017/jfm.2020.459

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