Phase Transition in Extended Thermodynamics Triggers Sub-shocks

Candi Zheng; Yang Wang; Shiyi Chen

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arXiv · 2304.10742

Phase Transition in Extended Thermodynamics Triggers Sub-shocks

Candi Zheng·Yang Wang·Shiyi Chen

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Abstract

Extended thermodynamics commonly uses polynomial moments to model non-equilibrium transportation, but faces a crisis due to sub-shocks, which are anomalous discontinuities in gas properties when predicting shock waves. The cause of sub-shocks is still unclear, challenging the validity of extended thermodynamics. This paper reveals, for the first time, that sub-shocks arise from intrinsic limitations of polynomials leading to a discontinuous phase transition. Therefore extended thermodynamics necessitates alternative moments beyond polynomials to avoid sub-shocks.

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Candi Zheng, Yang Wang, Shiyi Chen. 2023-04-21. Phase Transition in Extended Thermodynamics Triggers Sub-shocks. https://arxiv.org/abs/2304.10742

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