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arXiv · 2502.16597

Effects of reflection distance on Richtmyer-Meshkov instability in the reshock process: A discrete Boltzmann study

Huilin Lai·Chuandong Lin·Demei Li·Tao Yang·Yanbiao Gan·Lingyan Lian·Aiguo Xu
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Abstract

The Richtmyer-Meshkov (RM) instability occurs when a perturbed interface between two fluids undergoes impulsive acceleration due to a shock wave. In this paper, a numerical investigation of the RM instability during the reshock process is conducted using the two-component discrete Boltzmann method. The influence of reflection distance on the RM instability, including both hydrodynamic and thermodynamic non-equilibrium effects, is explored in detail. The interaction time between the reflected shock wave and the material interface varies with different reflection distances. Larger reflection distances lead to a longer evolution time of the material interface before reshock, resulting in more complex effects on the interface deformation, the mixing extent of the fluid system, and non-equilibrium behaviors after reshock. Additionally, while the reflection distance has a minimal impact on mixing entropy before the secondary impact, a significant difference emerges after the secondary impact. This suggests that the secondary impact enhances the evolution of the RM instability. Furthermore, non-equilibrium behaviors or quantities exhibit complex dynamics due to the influence of the transmitted shock wave, transverse waves, rarefaction waves, material interfaces, and dissipation/diffusion processes.

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Huilin Lai, Chuandong Lin, Demei Li, Tao Yang, Yanbiao Gan, Lingyan Lian, Aiguo Xu. 2025-02-23. Effects of reflection distance on Richtmyer-Meshkov instability in the reshock process: A discrete Boltzmann study. https://arxiv.org/abs/2502.16597

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