Active transition fixing and control of the boundary layer in airActive transition of flow over an airfoil surface and feedback control by sound is investigated in a wind tunnel at Caltech. Laminar instability forced by localized time dependent nonintrusive narrow heating strip causes abrupt changes in velocity to trigger instant transition at favorable pressure gradient. At zero and adverse pressure gradients these changes are only marginal. Feedback control by sound interaction at nearly normal incidence produces significant reduction in velocity perturbation in regions of transition. This reduction is in part at the expense of an increase in background disturbance since it is not possible to restore the flow to its undisturbed state.
Document ID
19850043799
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Maestrello, L. (NASA Langley Research Center Hampton, VA, United States)