Fluid-dynamic limit of the Enskog equation with the guaranteed H-theorem

Aoto Takahashi; Shigeru Takata

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arXiv · 2507.01341

Fluid-dynamic limit of the Enskog equation with the guaranteed H-theorem

Aoto Takahashi·Shigeru Takata

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Abstract

The fluid-dynamic limit of the Enskog equation with a slight modification is discussed on the basis of the Chapman-Enskog method. This modified version of the Enskog equation has been shown recently by the present authors to ensure the H-theorem. In the present paper, it is shown that the modified version recovers the same fluid-dynamic description of the dense gas as the original Enskog equation, at least up to the level of the Navier-Stokes-Fourier set of equations inclusive. Since the original Enskog equation is known to recover the fluid-dynamical transport properties well, this result implies that the modified version of the Enskog equation provides consistent descriptions both thermodynamically and fluid-dynamically.

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Aoto Takahashi, Shigeru Takata. 2025-07-02. Fluid-dynamic limit of the Enskog equation with the guaranteed H-theorem. https://arxiv.org/abs/2507.01341

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