Resonance Response Due To Shear Layer Vorticity in Cavity Exposed To High-Speed Freestream

A cavity exposed to a high-speed free stream will exhibit a resonance interaction between the shear layer over the cavity and acoustic waves in the cavity, developing discrete tones as predicted by the phenomenological model developed by Rossiter [1964] and refined by Heller [1971]. In this study, we experimentally observe the interaction between acoustic waves and vorticity within the cavity with a shadowgraph system and optically clear sidewalls, as well as discrete pressure transducers in the front and back walls. We demonstrate how the statistical distribution of flow physics events in the cavity produces some of the observed acoustic tones. Hitherto, all research has been conducted with cavities exposed to a continuous free stream; we will demonstrate how the response of the cavity aeroacoustic resonance is affected by a sliding door from fully closed to fully open in O(100) convective units.