Transition control of instability waves over a flexible surface in the presence of an acoustic fieldExperimental results are presented which demonstrate the coupling of a laminar boundary layer flow with a typical flexible aircraft panel. It is shown that the boundary layer induces plate oscillations which, in turn, perturb the flow at the same frequencies. This feedback mechanism is an inherent property of laminar boundary layer flow passing over a flexible plate. As a result, the flexibility of the plate becomes a source of early transition. The laminar boundary layer at the leading edge of the plate reacts to small, upstream, unsteady disturbances due to a streamwise pressure gradient. The experiments demonstrate that a nominal sound pressure incident at the leading edge triggers early transition. It is shown that transition can be delayed by activating a heat source at the leading edge of the plate which results in downstream cooling.
Document ID
19910027897
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Maestrello, L. (NASA Langley Research Center Hampton, VA, United States)
Grosveld, F. W. (NASA Langley Research Center; Lockheed Engineering and Sciences Co. Hampton, VA, United States)