A new technique for visualization of shock shapes in hypersonic shock tunnel

Based on the principle of dependence of the intensity and the spectrum of the spontaneous light emitted in an electrical discharge on the density and the temperature of the gas along the discharge path, a technique for flow visualization around the bodies flying at hypersonic Mach number is developed. The shock shapes over a flat plate with sharp leading edge at different angles of attack are visualized using this technique in IISc hypersonic shock tunnel HST1 at flow Mach number of 5.75. The visualized shock wave angles match very well with the theoretical values. The details of this new technique along with a few sample results are presented here