Simulations based on the Reynolds-averaged "compressible" Navier-Stokes equations were performed to study the effects of four turbulence models - realizable k-ε (RKE), renormalized group k-ε (RNG), shear-stress transport (SST) model, and stress-omega full Reynolds stress (RSM) model - in predicting shock-wave/boundary-layer interaction on a flat plate with bleed into a plenum through four rows of "90-degree" bleed holes that are arranged in a staggered fashion. The SST model was also used to examine the effects of the free stream Mach number (M_∞ = 1.6, 2.0, and 2.4) and the plenum back pressure for choked and unchoked bleed. Results obtained show all four models to predict a similar "barrier" shock structure in each bleed hole. Also, all models predicted similar bleed rates (less than 4% relative difference) that compare reasonably well with experimentally measured values. However, the four models differ significantly in how they predict the flow field between the bleed holes when there is an incident shock wave. The RKE and RNG models, which utilize the one-equation model in the near-wall region, predicted velocity profiles that are much fuller than those predicted by the SST and RSM models next to the wall. As a result, the RKE and RNG models predicted relatively small shock-induced separation bubbles. For the SST and RSM models, the predicted separation bubbles were much larger and were affected by both the incident shock and by the portion of the barrier shock that extends above the fiat plate. Since the production of turbulence is delayed in the RSM model, the mixing was less, and the predicted separation bubble was the largest. On the free stream Mach number, increasing it decreases the bleed rate because higher-speed flow is harder to turn into the bleed hole so that the effective area for bleed is less. Though bleed is less with the higher M_∞, the bleed was sufficient to control shock-induced flow separation. This is because the subsonic portion of the boundary layer is thinner with higher M_∞. When there is an incident shock wave on a flat plate with bleed into a common plenum, the bleed may be unchoked upstream of the incident shock and choked downstream of it and still produce good control of flow separation.
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