Numerical study of perturbed shock driven instability in a dilute gas-particle mixture

The effects of particles on the Richtmyer–Meshkov (RM) instability of a flat interface driven by perturbed and reflected shock waves are numerically investigated. By utilizing three different sizes of particles ($d=5\mu m$, $20\mu m$ and $50\mu m$) and two types of heavy gases (SF₆ and CO₂), the effect of the presence of particles with different sizes on the RM instability and the dynamic process of particle diffusion have been explored, respectively. The evolution of interface morphology under smaller particle ($d=5\mu m$ and $20\mu m$) conditions bears a striking resemblance to that of the condition without particles while the large particles ($d=50\mu m$) contribute to the formation of many “wrinkles” on the interface due to the large particle size and particle inertia. The addition of particles with smaller size ($d=5\mu m$ and $20\mu m$) can either slightly inhibit or promote the growth of the mixing width at the late stage of the interface evolution, depending on the extent of interface evolution. Both the particle size and the type of heavy fluid are able to influence the particle motion.