On the entropic property of the Ellipsoidal Statistical model with the Prandtl number below 2/3

Shigeru Takata; Masanari Hattori; Takumu Miyauchi

doi:10.3934/krm.2020041

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arXiv · 2212.13342

On the entropic property of the Ellipsoidal Statistical model with the Prandtl number below 2/3

Shigeru Takata·Masanari Hattori·Takumu Miyauchi

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Abstract

Entropic property of the Ellipsoidal Statistical model with the Prandtl number Pr below 2/3 is discussed. Although 2/3 is the lower bound of Pr for the H theorem to hold unconditionally, it is shown that the theorem still holds even for $\mathrm{Pr}<2/3$, provided that anisotropy of stress tensor satisfies a certain criterion. The practical tolerance of that criterion is assessed numerically by the strong normal shock wave and the Couette flow problems. A couple of moving plate tests are also conducted.

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Shigeru Takata, Masanari Hattori, Takumu Miyauchi. 2022-12-27. On the entropic property of the Ellipsoidal Statistical model with the Prandtl number below 2/3. https://doi.org/10.3934/krm.2020041

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