Effect of micro-ramps on supersonic boundary layer past a double wedge

The effect of micro-ramps on Mach 3 boundary layer structures past a double wedge was experimentally investigated in a supersonic low-noise wind tunnel using nano-tracer planar laser scattering (NPLS) technique. The fine structures of supersonic flow over the double wedge with and without the micro-ramps, as well as temporal and spatial evolutionary characteristics of the vortex structures with the micro-ramps, were revealed.