Oscillating shock impinging on a flat plate at mach 6

This work discusses the design, measurement and simulation of an experiment in a Mach 6 wind tunnel involving an oscillating shock impinging on a flat plate. The design of the oscillating shock-generator is performed using piston theory. The oscillation frequency is designed to be larger than 30 Hz, to match typical fuselage natural frequencies of hypersonic vehicles and technology demonstrators, such as the X-33 and the X-43. The shock generator is free to pitch, resulting in a shock that varies in intensity and impingement point, with a maximum flow deflection angle of 10 degrees. Transition appears to take place just downstream the separated region for both static (with a fixed flow deflection angle) and dynamic experiments. Transition decreases the peak pressure levels while determining a rise in the heat-flux distribution. The motion of the reattachment point appears to lag behind the numerical predictions by a fifth of the oscillation period. Görtler-like vortices are observed in the reattachment region; while their magnitude is a function of the shock strength, their spanwise distribution appears to be unaffected by the motion of the shock generator.