Understanding Micro-Ramp Control for Shock Boundary Layer Interactions

Abstract : Micro-vortex generators (micro-VGs) have the ability to alter the near-wall structure of compressible turbulent boundary layers in such a way that the flow becomes significantly less susceptible to separations and more stable to unsteady disturbances. Due to their extremely small size, micro-VGs are embedded in the boundary layer and may provide reduced viscous drag when compared to traditional vortex generators. Of several candidate micro-VGs, micro-ramps have been found to significantly impact shock boundary layer interaction flows, while being cost-effective, physically robust, and requiring no power sources. Thus detailed study of flow interactions with micro-ramps on a supersonic boundary layer at M=3.0 was investigated using monotone integrated Large Eddy Simulations (MILES) and Reynolds Averaged Navier-Stokes (RANS). A rescale-recycle method was used to efficiently generate turbulent in-flow conditions. Studies showed that the vortical structure generated from the micro-ramp flows through the separation region caused by the impinging shock, which helped to reduce the area of separation.