The Richtmyer–Meshkov instability (RMI) of a twice-shocked gas interface is studied using high-speed planar-laser induced fluorescence (PLIF) in the Wisconsin Shock Tube Laboratory’s vertical shock tube. The initial condition (IC) is a shear layer with broadband diffuse perturbations at the interface between a helium-acetone mixture and argon. This IC is accelerated by a shock of nominal strength $M=1.8$, and then accelerated again by the transmitted shock that reflects off the end wall of the tube. An estimate of the light gas mole fraction is extracted from high-speed imaging using an iterative process that accounts for the nonlinear temperature dependence of the acetone’s fluorescence quantum yield (FQY) and absorption cross-section. A vorticity deposition model for the initial growth rate after re-shock is compared with the Mikaelian model for re-shock. Previously used in literature, the number of generations is shown to naturally arise from a normalisation of the scalar transport equation. A self-similar analysis is then performed using the mole fraction data to explore the evolution of the RMI after reshock and the higher order moments of the light gas mole fraction are compared with a proposed model.

在威斯康星州激波管实验室的垂直激波管中使用高速平面激光诱导的荧光（PLIF）研究了两次激射气体界面的Richtmyer-Meshkov不稳定性（RMI）。初始条件（IC）是剪切层，在氦-丙酮混合物和氩气之间的界面处具有宽带弥散扰动。该IC通过标称强度的冲击而加速$\mathrm{中号}=\mathrm{1个}。8$，然后通过从管的端壁反射的传递的冲击再次加速。使用迭代过程从高速成像中提取轻质气体摩尔分数的估计值，该过程考虑了丙酮的荧光量子产率（FQY）和吸收截面的非线性温度依赖性。将重新电击后初始增长率的涡度沉积模型与重新电击的Mikaelian模型进行比较。以前在文献中使用过，世代数显示为自然地来自标量输运方程的归一化。然后使用摩尔分数数据进行自相似分析，以探索重震后RMI的演变，并将轻质气体摩尔分数的高阶矩与提出的模型进行比较。