Investigation of Unswept Normal Shock Wave/Turbulent-Boundary-Layer Interaction Control

Abstract

An analytical model for the unswept normal shock wave/turbulent-boundary-layer interaction control using an upstream and downstream unimorph piezoelectric flap actuator has been proposed. The amount of flap deflection controls the bleed/suction rate through a plenum chamber. The cavity allows rapid thickening of the boundary layer approaching a normal shock wave, which splits into a series of weaker shocks forming a lambda shock foot, leading to a reduction in the wave drag. The analysis provides an understanding of the control influences produced in an experimental investigation of an unswept normal shock wave/turbulent-boundary-layer interaction at a Mach number of 1.5. It has also been validated by application to the normal shock wave/boundary-layer interaction control system using mesoflaps for aeroelastic transpiration described in previous transonic/supersonic shock wave/ boundary-layer interaction studies.