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To examine the potential of micro vortex generators for shock/boundary-layer interaction control, a detailed experimental and computational study in a supersonic boundary layer at M 3:0 was undertaken. The experiments employed a flat-plate boundary layer with an impinging oblique shock with downstream total-pressure measurements. The moderate Reynolds number of 3800 allowed the computations to use monotone-integrated large eddy simulations. The monotone-integrated large eddy simulations predictions indicated that the shock changes the structure of the turbulent eddies and the primary vortices generated from the microramp. Furthermore, they generally reproduced the experimentally obtained mean velocity profiles, unlike similarly resolved Reynoldsaveraged Navier-Stokes computations. The experiments and monotone-integrated large eddy simulations results indicate that the microramps, for which the height is h 0:5, can significantly reduce boundary-layer thickness and improve downstream boundary-layer health as measured by the incompressible shape function H. Regions directly behind the ramp centerline tended to have increased boundary-layer thickness, indicating the significant threedimensionality of the flowfield. Compared with baseline sizes, smaller microramps yielded improved total-pressure recovery. Moving the smaller ramps closer to the shock interaction also reduced the displacement thickness and the separated area. This effect is attributed to decreased wave drag and the closer proximity of the vortex pairs to the wall. Nomenclature A sep = separation area a = speed of sound c = cord length of the microramp D = width of the computational domain d = width of the microramp dt = differential time dx = differential length in the streamwise direction dy = differential length in the normal direction dz = differential length in the spanwise direction E = height of the computational domain H = incompressible shape factor h = microramp height L = length of the computational domain M = Mach number P = pressure P o = total pressure Re ref = Reynolds number based on ref s = spacing between adjacent microramps at the centerline T = temperature t = fluid convection time scale U = average streamwise velocity U = frictional velocity u = instantaneous streamwise velocity u 0 = streamwise fluctuation the velocity v = normal velocity w = spanwise velocity W = weighting function x = streamwise distance y = normal distance relative to solid wall z = spanwise distance relative to center of domain = total-pressure recovery factor = frictional velocity ratio = specific heat ratio t = time step x = streamwise length of the computational cell = boundary-layer thickness ref = displacement thickness at x 0 but with no shock effects = k direction in the computational domain = wall normal coordinate normalized by boundarylayer thickness = von Kármán constant = i direction in the computational domain = integration time = integration time normalized by the freestream flow convection time ! = kinematic viscosity at wall = j direction in the ...

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A test was conducted of a generic two-dimensional mixed compression inlet flow field simulator model in the AFRL Trisonic Gasdynamic Facility (TGF) to evaluate non-bleed Shock Wave Boundary Layer Interaction (SWBLI) flow control. The flow field simulator model incorporated a compression ramp with variable angle to allow investigation of differing shock strengths and a vertically translating upper cowl surface to allow throat height compensation for differing boundary layer thicknesses. The model also featured a rectangular to round diffuser with a 40 probe Aerodynamic Interface Plane (AIP) total pressure rake at the end of the diffuser and a primary flow plug to allow variations in mass flow. Testing was accomplished at a free stream Mach number of 3.0. A bleed optimization was performed on the ramp and cowl bleed zones with the four throat and two forward sidewall bleed zones being held constant. Center line static pressures along with bleed flow parameters and boundary layer profiles on the ramp surface were recorded. Schlieren images of the shock wave pattern along the ramp were also recorded. The ramp SWBLI bleed flow control was replaced with various micro vortex generator configurations. Test results show that several of the vortex generator configurations had the ability to effectively replace the bleed flow control and prevent inlet un-start to equivalent ramp angles as long as adjustments were made to the throat height to allow for the increased mass flow and boundary thickness.