Three-Dimensional Hypersonic Boundary Layer Stability and Transition

The stability and transition of three-dimensional boundary layers was studied. In the first phase of the investigation, arrays of hot film probes were used to measure the three-dimensional structure of instability waves on an axisymmetric cone at Mach 8. In the second phase, linear stability theory was used to design a cone with an elliptic cross section, which was also tested at Mach 8. Results show that disturbances on the axisymmetric cone travel in wave packets with predominantly zero wave angle. On the elliptic cone, only weak evidence for stationary waves was found. The predominant waves were traveling waves at about 12 kHz. Additional waves, probably second mode, occurred near 80 kHz.Air Force Research Lab Wright-Patterson AFB OH Air Vehicles Directorate is the author of 'Three-Dimensional Hypersonic Boundary Layer Stability and Transition' with ISBN 9781423547921 and ISBN 1423547926.