The impact of weak shock waves on the flow in the boundary layer of a flat plate with a variable sweep angle of the leading edge

The impact of weak shock waves on the boundary-layer flow of a flat blunt plate installed along the stream was experimentally studied for different sweep angles of the leading edge of the plate at Mach number 2. The shock waves in the incoming flow in the form of an N-wave were generated by 150×7×0.13-mm two-dimensional roughness provided on the side wall of the T-325 wind tunnel. It was confirmed that, when an N-wave was incident onto the plate leading edge with zero sweep angle, generation of longitudinal vortices accompanied by an increase in the pulsation level and by a change in the spectral composition of perturbations, was observed in the boundary layer. Anemometric data showed that, when the sweep angle of the leading edge changed from 0 to 25 degrees under the impact of the “catching-up” incident weak shock wave, the widening of the vortex in the supersonic boundary layer occurred.