Control of Transition in Supersonic Boundary Layers: Experiments and Computations (Keynote)

The present work addresses a technique that can lead to drag reduction on supersonic wings by means of passive laminar flow control. Recent developments in the stability and transition in swept-wing flows in low-disturbance environments have offered the promise of controlling transition without suction. It has been demonstrated in low-speed experiments that distributed roughness near the attachment line can control the crossflow instability provided the roughness spacing is below a critical value. This is extended to supersonic flow over highly swept wings where the combined computational and experimental work gives design criteria for airfoils swept beyond the characteristic Mach angle.Copyright © 2002 by ASME