Shock-Wave Boundary-Layer Interaction Control on a Compression Corner Using Mechanical Vortex Generators

Introduction

Shock-wave boundary-layer interactions (SWBLI) are prevalent in many supersonic applications, e.g., over deflected flaps, fore-body ramp corners, on leading edges where the bow shock from the vehicle nose interferes, along axial compression corners inside air-inlets, shock reflection and crossing-shock interactions in the inlets etc. The adverse pressure gradient across the interaction shock can cause separation of the incoming boundary-layer leading to increased aerodynamic drag, heat transfer and unsteady pressure loads. Much of the early work over forward-facing steps [1], un-swept compression ramp flows [2-4] and in interactions induced by blunt fins [5], circular cylinders and sharp fins at angle of attack [6] was focused on understanding the dynamic/unsteady behavior of these interactions. It has been observed that the flow in these interactions in unsteady if the pressure ratio across the oblique shock is such that the mass of the fluid reversed at the reattachment point does not balance the scavenged fluid from the separated region [7-8]. As a result, the separated region “breathes” and during one half of pulse, mass is injected into it while during the other half it is ejected out resulting into an unsteady mass exchange.