Frequency-flow speed dependence of structural response to turbulent boundary layer pressure excitation

Abstract

A rectangular simply supported plate is used to illustrate the differing dependencies on center frequency and flow speed of the spatially averaged one-third-octave band mean squared acceleration levels of a structure due to different mechanisms of response to turbulent boundary layer (TBL) excitation. The two mechanisms described are direct excitation of resonant modes by the TBL components in the neighborhood of the wave numbers of the resonant modes, and the coupling into the resonant modes of those TBL components in the neighborhood of the TBL convective peak. Estimates of the mean-squared response are made for different representations of the TBL wave-number-frequency spectrum. When determination of the dominant response mechanism is important, it appears that it can be made by performing a regression analysis on measured results and comparing the derived parameters to the alternative theoretical estimates.