Impact of Cavity Edges Shape on Aerodynamic Noise

In this article, the analysis of influence of cavity edge shapes on flow-generated noise is performed. The acoustic wave propagation in the channel, that result from the flow, was analyzed. Shape of upstream and downstream edges was modified. The hybrid method based on Navier-Stokes and Perturbed Convective Wave Equation was used to solve the unidirectional coupling. The research showed a significant influence of the modification of the shape of the cavity edges on the generated noise. The change of downstream corner allowed for significant reduction of noise in the entire analysed band and allowed for the reduction of overall sound pressure level (OASPL) by 5 dB. Modifications of the upstream edge did not bring such differences, change in OASPL was up to 1 dB. The obtained spectra of the sound pressure level showed compliance with the calculated natural frequencies of the analysed object, as well as with some of the Rossiter modal frequencies, typical for the phenomena occurring in the cavities.