On the Free Shear Layer Downstream of a Backstep in Supersonic Flow

Abstract

The free shear layer downstream of a backstep immersed in a supersonic stream is analyzed. The effects of the initial boundary layer and the expansion at the step corner are taken into account. The shear layer is divided into two distinct regions, an outer rotational nondissipative region and an inner dissipative locally similar mixing region which spreads both into the rotational outer region and the wake. The dynamic characteristics of the shear layer including the rate of spread of the inner mixing layer and the location of the jet boundary streamline are determined by an integral technique. Comparison of predicted velocity profiles with experimental data shows reasonable agreement.