Hypersonic Shockwave/Turbulent Boundary-Layer Interactions on a Porous Surface

摘要

In previous work, Chokani and Squire1 have shown that under transonic conditions passive control in the form of a porous surface in the region of the shock/boundary-layer interaction weakens the pressure rise through the interaction. The more gradual pressure rise was seen to produce a weaker shock wave and beneficial drag reductions. These authors compared Navier-Stokes calculations and wind-tunnel data and observed the presence of a thin shear layer over the porous surface that was independent of the boundary layer. They suggested that this shear layer altered the effective surface geometry in the interaction region, which provided the mechanism for weakening the shock wave. This observation suggested that shock-induced separation may be delayed or reduced. The presence of the shear layer, however, was also observed in their calculations to increase the skin friction. Since such detailed data were not obtained in the experiment, the numerical investigation was beneficial in order to fully determine if other benefits of passive-control methods outweigh the skin friction penalties.