Jet Formation of SF₆ Bubble Induced by Incident and Reflected Shock Waves

We present computational results of two different cases on the evolution of shock-SF₆ heavy bubble interaction. And the shock-focusing processes and jet formation mechanisms are analyzed by using the high resolution of computation schemes, and the influence of reflected shock wave is also investigated. It is concluded that there are two stages in the shock-focusing process behind the incident shock wave. However, different jet formation mechanisms are found behind the reflected shock wave in case 2, owing to the gas being with a rightward velocity before the reflected shock wave impinges. The multi-influences of different shock waves and high-pressure zones in the vicinity of the bubble interface could induce a leftward velocity, which can promote the formation of jets. In addition, the time for the bubble evolution before the impingement of reflected shock wave in case 1 is larger than that in case 2, so the distorted bubble is getting more flat, which would induce the weakening of the influence of reflected shock in the bubble.