GALCIT Colloquium

In this presentation, I will summarize the results of series of experimental studies investigating the transition of hypersonic boundary layers over straight cones (with and without bluntness), cone/flares, and a cone/cylinder, conducted in a variety of facilities (both low- and high-enthalpy). Ultra-high-speed calibrated schlieren, supplemented by high-frequency surface-pressure measurements, provide a global picture of the development of the various instability mechanisms present in the different conical configurations. I will also describe the development of a global temporal reconstruction technique that allows the effective sampling frequency to be increased well beyond the camera frame rate, allowing the investigation, for example, of higher harmonics and the application of modern modal-reduction techniques. A particular focus will be recent measurements on a cone/flare carried out at Mach 12 in the VKI Longshot facility.