Mixing-Enhancement Mechanism of Richtmyer-Meshkov Instability at Different Parameters

The evolution of Richtmyer-Meshkov(R-M) instability induced by a shock wave on a H₂O and N₂ mixture interface was numerically analyzed. Two-dimensional compressible Navier-Stokes equations were discretized and solved by finite difference method. The convective terms were discretized by the 5^th-order characteristic-wise hybrid compact-WENO scheme, the transportive terms were discretized by the 6^th-order symmetric compact scheme, and a 3^rd-order explicit Runge-Kutta method was employed for time marching. Results show that both interface amplitude and shock wave strength can largely affect the mixing procedure. When the interface amplitude and shock wave strength increase, the vorticity field near the interface is strengthened and hence the mixing is enhanced.