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arXiv · 2104.14328

Entropy production estimate for the ES-BGK model with the correct Prandtl number

Doheon Kim·Myeong-Su Lee·Seok-Bae Yun
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Abstract

In this paper, we establish the entropy-entropy production estimate for the ES-BGK model, a generalized version of the BGK model of the Boltzmann equation introduced for better approximation in the Navier-Stokes limit. Our result improves the previous entropy production estimate [39] in that (1) the full range of Prandtl parameters $-1/2\leq\nu <1$ including the critical case $\nu=-1/2$ is covered, and (2) a sharper entropy production bound is obtained. An explicit characterization of the coefficient of the entropy-entropy production estimate is also presented.

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Doheon Kim, Myeong-Su Lee, Seok-Bae Yun. 2021-04-29. Entropy production estimate for the ES-BGK model with the correct Prandtl number. https://arxiv.org/abs/2104.14328

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