Prediction of flow-induced structural vibration and sound radiation using energy flow analysis

The energy flow analysis method was used to predict the structural vibratio n response and the radiated sound power of a plate excited by wall pressure fluctuations under turbulent boundary layers, and separated-reattached flo ws. This method allows the spatially averaged energy density response to be calculated for non-uniform, distributed excitations while taking hydrodyna mic flow/structural coupling effects into consideration. The power input wa s calculated using well known analytical models for the plate mechanical im pedance and empirical models for the surface pressure cross-power spectral density and/or wave number-frequency spectral density. The Smol'yakov-Tkach enko model was used to estimate the fluctuating pressure field underneath t urbulent boundary layer flows. The Corcos model was used to estimate the wa ll pressure field under non-uniform, separated-reattached flows. Experiment s were performed in order to evaluate the energy flow model. A clamped plat e installed in a quiet, low-speed wind tunnel was used. The wall pressure f luctuations, the plate vibration response, and the acoustic pressure radiat ed from the plate were measured. The energy flow analysis method was found to provide reasonably accurate predictions of the frequency-averaged transv erse velocity response of the plate at high frequencies. The acoustic press ure radiated on the quiescent side of the plate was also predicted with com parable accuracy. (C) 1999 Academic Press.