Three-Dimensional Numerical Investigation of Deformation and Instability of High-Density Bubble Induced by Incident and Reflected Shock Waves

The three-dimensional deformation and instability of high-density spherical bubble induced by incident shock wave and its reflected wave were studied numerically by using large eddy simulation method. The computational model was validated by the experimental results. The emphasis was placed on the interaction of reflected shock wave with the deformed high-density bubble. The formation and three-dimensional instability of vortex rings were discussed. The results show that the high-density spherical bubble can form the vortex rings with the different rotating directions along the streamwise direction induced by incident and reflected shock waves due to the baroclinic effect. The vortex rings induced by reflected shock wave have the less strength, and therefore are more likely unstable, and even can form a complicated small-scale structure dominated by the streamwise vortices.