Vortex formation in shock interaction with a deformable ellipsoidal particle

We present our numerical study of shock interaction with a deformable ellipsoidal particle. Numerical simulations were carried out using fully resolved multi–material Euler equations for shock interaction with a deformable aluminum particle in nitromethane. We compute the circulation and the unsteady drag coefficient as a function of time. As the shock propagates over the particle we observed the vorticity production owing to the baroclinic effect and it is primarily initiated near the interface of the particle. After the passage of a shock over a particle, the generated vortex traverses downstream, thus generating low pressure in the downstream side of the particle. This mechanism leads to the generation of a quasi–steady drag force even after the passage of the shock. The peak circulation is computed as a function of shock Mach number and the initial ellipticity of the particle, and we show that the absolute value of the peak circulation increases with increasing shock Mach number and ellipticity of the particle.