Görtler-type vortices in hypersonic flows: the ramp problem

This paper deals with the wall heat flux measurements in the presence of thermal striations that can occur in the reattaching flow after a Mach 7.1 shock wave-boundary layer interaction on a 15° flap. Two different experimental techniques were used: thin skin with thermocouples and thin film with infrared thermography. Special care was taken to correct the lateral conduction effects. They can be important because of the small wavelengths of the spanwise striations. The influence of the Reynolds number was assessed by varying the unit Reynolds number and the length of the flat plate while keeping the same leading edge geometry. The effect of a sinusoidal perturbation at the leading edge also was studied. Finally, Navier Stokes laminar computations were performed to obtain the proper level of the laminar heat flux and to analyze the effect of the leading edge thickness. The calculations confirm the strong influence of the leading edge on the interaction phenomena.