A Hybrid UWPW-FEM Technique for Vibroacoustic Analysis of Panels Subject to a Turbulent Boundary Layer Excitation

A hybrid uncorrelated wall plane wave (UWPW) and finite element method (FEM) technique is introduced to the predict vibroacoustic response of a panel under turbulent boundary layer (TBL) excitation. The spectrum of the wall pressure fluctuations is evaluated from the TBL parameters and by using semi-empirical models from literature. TBL parameters can be estimated by different means, using theoretical formula, Reynolds-averaged Navier Stokes (RANS) simulations or experimental data. The wall pressure field (WPF) underneath the TBL is then synthesized by realisations of uncorrelated wall plane waves. The FEM is employed to compute the structural and acoustic responses of the panel for each realisation of uncorrelated wall plane waves. The responses are then obtained from an ensemble average of the different realisations. Selection criteria for cut-off wavenumber, mesh size and number of realisation are discussed. Two simply-supported baffled panels under TBL excitation are examined. Numerical results are compared with analytical results using the sensitivity functions of the panels, showing excellent agreement.