Mach number impact on Richtmyer-Meshkov instability in shock-refrigerant-22 bubble interaction

Abstract

This study carries out a numerical assessment of incident shock Mach number effects on the Richtmyer-Meshkov (RM) instability after a shock wave impulsively drives a heavy cylindrical bubble. The bubble is composed of refrigerant 22(R22) gas, which is surrounded by nitrogen gas. Four different shock Mach numbers are considered: M s =1.15, 1.27, 1.50, and 1.90. To produce high-resolution numerical simulations of the RM instability, we employ a two-dimensional explicit modal discontinuous Galerkin scheme. The numerical outcomes show that the growth of RM instability in a heavy bubble is significantly influenced by the incident shock Mach number. The shock Mach number has a considerable impact on flow morphology, leading to complex wave patterns, shock focusing, the formation of jets, bubble deformation, and the development of vortices. Due to the bubble’s converging structure, there is a localized area of high pressure, which results in the generation of an outward jet. As the shock Mach number rises, it is found that the bubble deforms differently. Physical phenomena including the creation of vortices and the evolution of enstrophy are then used to explore the impacts of shock Mach numbers.