A mechanism of vortex generation in a supersonic flow behind a gas-plasma interface

Abstract

The origin of a vortex structure generated during the shock-plasma interaction is investigated. A two-dimensional model based on the shock refraction mechanism successfully unifies the vortex generation with major co-processes typical for the interaction and thus well fits in their cause-and-consequence relationship. Numerical simulations demonstrated the possibility of an intense vortex generation with a continuous positive dynamics as the shock crosses the interface. It was shown that while the vorticity is triggered by the shock refraction on the interface, it is the gas parameter distribution that distinctively determines the parameters of the vortex evolution. The proposed model also provides an insight into interesting aspects of the refraction effects for both, the shock wave and the flow behind it (double refraction). The results are applicable to the problems of energy deposition in a hypersonic flow, a flame-shock interaction, in combustion, in astrophysics, and in the fusion research.