Prediction of the Pressure Oscillations in Cavities Exposed to Aerodynamic Flow

Abstract : Cavities, or rectangular cutouts, exposed to fluid flow can produce an intense aero-acoustic environment. Past experience has shown that severe fluctuating pressures exist in open aircraft weapon bays under certain flight conditions. The aircraft designer must be able to predict the fluctuating pressure environment of cavities in order to assess the effects on the internally carried stores or near-by structure. Prediction methods were formulated based primarily on data from flight tests on cavities with length-to- depth-ratios of 4, 5 and 7 over a Mach number range of 0.6 to 1.30. Available data in the literature were then used to extend the range of application of the prediction method to cavities with length to depth ratios from 2 to 7 and for Mach numbers from 0.5 to 3.0.