Statistical Properties of Pressure Loadings and Vibroacoustic Response of a Simplified Side Glass Induced by the Flow over Generic Flow-deflector and Side-mirror

Abstract

The statistical description of the wall pressure fluctuations in a non-equilibrium turbulent boundary layer (TBL) on a plate with two typical bluff bodies a side mirror and a flat fence is presented. To achieve statistically converged turbulent flow, a long time history computational fluid dynamics (CFD) simulation was conducted with the Lattice-Boltzmann solver PowerFLOW. It provided the unsteady wall pressure on the plate. Mean flow, wall pressure spectra and two point correlations of the wall-pressure results are validated for both cases with experiments run in the anechoic wind tunnel at Purdue University. From a spatial temporal analysis of the turbulent flow the convection and acoustic zones are captured correctly, which are major sources of excitation and transmission respectively. Using the CFD wall-pressure coherence on the plate, zonal Corcos’ model parameters like convection velocity and decay coefficients have been determined by least-square curve fitting. The identified empirical model parameters are validated with experimental values and later used to predict the vibroacoustic indicators for the plate. Vibroacoustic indicators for a side mirror case are calculated using both CFD-derived parameters and finite element method. These results are validated with experiments on a plate-cavity system.