中文摘要：

为了探寻研究Richtmyer-Meshkov（RM）不稳定性的新方法，采用耦合双分布函数格子Boltzmann方法（LBM），对激波作用下两种不同密度流体交界面的演化过程进行了数值模拟研究，着重讨论了RM不稳定性的行程和演化特征，给出了交界面的扰动增长率的变化规律，同时还研究了激波强度对扰动振幅的影响．结果表明：由于受RM不稳定性的影响，两种不同密度流体的交界面上，重流体演化成尖顶结构，而轻流体演化成气泡结构，最终由于斜压效应重流体的尖项转变成蘑菇头形状；交界面扰动增长率与Zhang-Sohn模型较吻合；激波强度越大，扰动振幅增长率越高．研究表明所提的方法可以用于RM不稳定性的研究，有望成为两相流研究的新途径．

英文摘要：

To seek a new method to study the Richtmyer-Meshkov（RM） instability, a numerical study was performed for the evolution of the interface between two layers of fluid with different densities using the coupled double distribution function lattice-Boltzmann method （LBM）. The research focused on the RM instability and the perturbation growth rates of the interface were presented. The influence of the Mach number upon the perturbation growth rate was explored. The results show that due to the RM instability, the heavy fluid falls to generate a spike and the light fluid rises to form a bubble, and at last the head of the spike changes to mushroom shape. The numerical perturbation growth rate is in agreement with the result by the Zhang-Sohn model. The perturbation growth rises with an increase in the Mach number of shock wave. It can be concluded that the present method is an efficient approach to the simulation for the RM instability and two-phase flow.