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arXiv · 1401.7523

On Hyperbolicity of 13-Moment System

Zhenning Cai·Yuwei Fan·Ruo Li
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Abstract

We point out that the thermodynamic equilibrium is not an interior point of the hyperbolicity region of Grad's 13-moment system. With a compact expansion of the phase density, which is compacter than Grad's expansion, we derived a modified 13-moment system. The new 13-moment system admits the thermodynamic equilibrium as an interior point of its hyperbolicity region. We deduce a concise criterion to ensure the hyperbolicity, thus the hyperbolicity region can be quantitatively depicted.

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Zhenning Cai, Yuwei Fan, Ruo Li. 2014-01-29. On Hyperbolicity of 13-Moment System. https://arxiv.org/abs/1401.7523

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