Film cooling with normal injection into a supersonic flow

A it experimental study of film cooling with subsonic gas injection into a ma instream witha Mach number of 2.90 is reported. Air, used us both the mainstream and secondary fluids, is injected normal to the surface of a flat plate through a short porous section into a two-dimensional turbulent boundary layer. The secondary fluid enters the boundary layer with a mass velocity which ranges from 0.0085 to 0.0223 of the free-stream value. The adiabatic wall temperatures are presented as the film-cooling effectiveness. The results of the present study, when the proper choice is made for the reference stale used to account for fluid property variations across the high-speed boundary layer, are in good agreement with previous investigations in incompressible flows.