Shock–Boundary Layer-Interaction Control Through Recirculation in a Hypersonic Inlet

Abstract

This technical brief presents a flow separation mitigation device, called cavity-recirculator that can be used to control flow separation during shock wave–boundary layer interaction (SBLI) in high-speed intake flows. The cavity-recirculator isolates the flow separation bubble generated at the SBLI spot, thereby thinning the boundary layer and reducing the blockage of the inviscid stream in the duct. The device has a potential application in scramjet engine intakes/isolators. The cavity-recirculator was tested on a single-ramp-compression intake model in a hypersonic shock tunnel, in a freestream of Mach 8 (±0.1). The device operation and effectiveness were assessed by flow visualization and pressure measurements in the test model. The measurements and visualization displayed a mitigation of flow separation through an improved flow field with a single shock train and the absence of flow separation shock, in the inlet.