Aero-Optical Measurements of the Response of a Thin Panel at Mach 6

An experiment was recently conducted in the Air Force Research Laboratory Mach 6 High Reynolds Number Facility to observe the response of a generic vehicle wedge-mounted, thin metallic panel. A Shack–Hartmann wavefront sensor was used to measure aero-optical distortions in the boundary layer developing over the flexible panel. Localized buckling and fixed-frequency oscillations of the panel were detected using the wavefront sensor. The root mean square and power spectral density of the optical path difference obtained over the flexible panel resembled freestream measurements for deformations toward the cavity. This work introduces a novel application of a Shack– Hartmann wavefront sensor, providing wall-normal variation of the aero-optical distortions in the boundary layer developing over a flexible model. The initial findings of this study indicate that a Shack–Hartmann wavefront sensor can be used to nonintrusively detect fluid–structure coupling.