Improved mixing-width model for the linear stage of reshocked Richtmyer–Meshkov turbulence

Abstract

Turbulent mixing induced by reshocked Richtmyer–Meshkov instability widely occurs in both natural phenomena, such as supernova explosions, and high-energy-density applications, such as inertial confinement fusion. As the most important global quantity, the mixing width has been used and modeled to describe the reshocked multimode Richtmyer–Meshkov instability flow. Among the available models, Mikaelian's linear/nonlinear matching model has been widely recognized. However, it is unsatisfactory for predicting the linear growth rate immediately after reshock. To overcome this limitation, in this paper, we derived an improved model. Compared with Mikaelian's model, the improved model uses the same model coefficient of the linear growth and ensures the continuity of the mixing-width growth rate before and after reshock. Consequently, it agrees well with the results of experiments and simulations. This result is of great significance for clarifying the long-standing divergences in the model coefficient in the literature, and it sheds light on the study of reshocked Richtmyer–Meshkov turbulence.