Diffraction patterns of a shock wave interacting with strong/weak vortices

Abstract

A shock wave undergoes severe distortion as it interferes with a vortex. Patterns of shock diffraction heavily depend on the strength of the impinging shock and the vortex. Two parameters, the incident shock Mach number (M_s) and the maximum vortex Mach number (M_v,max), naturally play an important role in the shock-vortex interaction physics. In this paper, using Navier-Stokes equations, we investigate numerically the shock-vortex interaction patterns when the vortex is strong and weak. Strong vortex is referred to the case when some part of the flow field in the vortex becomes supersonic (M_v,max>1) and the weak vortex to the case when the entire flow field is subsonic (M_v,max<1). Weak waves are explained, radiated in the shock diffraction process by the strong vortex, such as the transmitted shock (TS) and the reflected wave (R).