Date of Award


Degree Type


Degree Name

Master of Science in Aeronautical and Astronautical Engineering


Aeronautics and Astronautics

Committee Chair

Steven Schneider

Committee Member 1

Sally Bane

Committee Member 2

Bradley Wheaton


Boundary-layer instability and transition was measured on a 7◦ cone with highly-swept fins at 0◦ angle of attack in a Mach-6 quiet tunnel. Effects of fin sweep angle, fin bluntness, and nosetip radius were assessed. Using temperature-sensitive paint and piezoelectric fast pressure transducers, transition was measured in all configurations. Some features present under quiet flow were not seen under noisy flow. Multiple streaks of heat transfer with peaks near 5 kW/m2 were noted on the cone surface. More streaks appeared and the streaks spread as the Reynolds number increased. Power spectral density plots were calculated from the pressure transducer data displaying two possible instabilities, one at low frequency and another at high frequency. Several heat-transfer streaks are also seen on the fin surface. The number of streaks appears invariant with Reynolds number. Increasing sweep, decreasing fin bluntness, and increasing nose radius delayed transition.