| A numerical study of the interaction between a supersonic streamwise vortex and an oblique shock is performed by solving the unsteady, three-dimensional, compressible Euler equations. The numerical simulation involves establishing an oblique shock of given strength, introducing a vortex at the inflow plane, convecting it downstream towards the shock, and allowing it to interact with the oblique shock. The tangential velocity is obtained by using a Burgers' vortex model and the characteristic velocity deficit through the vortex is also modeled using an analytical function. The inviscid oblique shock/vortex interaction (OSVI) flow-fields are compared to experimental results, while a parametric study is designed to ascertain the effects of vortex strength, velocity deficit, and Mach number on the OSVI. Three distinct types of interactions--weak, moderate, and strong--are observed, depending very strongly on the streamwise velocity deficit and, to a lesser degree, on the strength of the vortex.;In the second part of this work, the three-dimensional Parabolized Navier-Stokes equations are solved in a non-reacting mode to investigate the mixing enhancement resulting from the interaction of a parallel-injected swirling helium jet and an oblique shock. The effects of swirl on the mixing performance are studied by considering various strengths for the swirling jet and comparing the mixing performance to that of a jet with no swirl. In addition, the influence of jet-to-freestream pressure ratio on mixing is also investigated using an overexpanded and an underexpanded swirling jet and comparing their performance to a swirling jet with matched pressure. Several parameters are chosen to evaluate the mixing performance including the decay of maximum helium mass fraction, the area occupied by the jet, the fraction of total mass flux of the helium jet present at various concentrations, an integral measure of vorticity change, and the total entropy rise.;The weak interaction is characterized by a slight distortion of the shock and vortex with the resulting flowfield being supersonic everywhere. The moderate interaction, however, results in a more pronounced distortion of the shock creating a small pocket of subsonic flow downstream of the interaction. In addition, the incident vortex is highly distorted by the shock and eventually splits up into two counter-rotating vortices. In the strong interaction, due to the formation of a large subsonic region, a dramatic reorganization of the original shock occurs, accompanied by a region of reversed subsonic flow, a stagnation point, and a drastic expansion of the vortex core, all of which are characteristics of vortex breakdown.;The addition of swirl increases the jet-to-injector area by 3.7, compared to 3.0 for the non-swirling jet. This study also finds that with the addition of swirl, a higher fraction of total helium mass flux exists at lower concentrations which is advantageous for efficient combustion. The analysis based on total entropy increase indicates that there is only a small penalty paid with the addition of swirl. It is observed that the jet with the lower pressure and momentum provides better mixing performance than the higher pressure jet. The strength of the high-pressure swirling jet decreases after injection and results in a weaker interaction with the shock. |
