Experimental studies of supersonic film cooling with shock wave interaction

The supersonic film cooling was tested in the Mach 2.35 wind tunnel to investigate the effect of the external shock wave on the film cooling. The coolant was injected with sonic speed. The weak shock wave with the pressure ratio of 1.21 did not reduce the film cooling effectiveness. The stronger shock wave with the pressure ratio of 1.44 decreased the effectiveness of the film cooling in the restricted region. The decrease of the effectiveness was mainly the result of the increase of the adiabatic wall temperature by the decrease of the local Mach number. The increase of the heat transfer coefficient must be considered as well as that of the adiabatic wall temperature. In the region of the interaction, energy and mass were not transferred, but the momentum was transferred from the primary flow to the coolant