Injection slot location for boundary layer control in shock-induced separation

Abstract

An experimental investigation of the effect of tangential air injection in controlling shock-induced turbulent boundary-layer separation is presented, in particular when the injection slot is located inside of what would otherwise have been the recirculating zone in a separated flow. The experiments were carried out at a freestream Mach number of 2.5 in the separated flow induced by a compression corner with a 20 ° angle. The observations made were wall static pressures, pitot profiles, and schlieren visualizations of the flow. The results show that the present location for injection is more effective in suppressing boundary-layer separation than the more conventional one, where the slot is located upstream of where separation would occur in the absence of injection.