Structural/Acoustic Sensitivity Analysis of a Structure Subjected to Stochastic Excitation

Abstract

A development for computing the structural/acoustic sensitivity of systems subjected to stochastic excitation is presented. Previous work in the area of structural/acoustic sensitivity analysis considered systems subject to deterministic excitations. The sensitivity computation depends on the excitation; therefore, new algorithms are developed to account for stochastic excitation, The structural/acoustic sensitivity is calculated using finite element methods, boundary element methods, and stochastic analysis techniques. Structural/acoustic sensitivities for the radiated sound pressure spectral density and the radiated sound power are computed. The sensitivity values are calculated with respect to a set of sizing structural design variables. The random pressure distribution exerted on the surface of the structure by turbulent boundary-layer flow is considered as excitation. Two classic structural models, a simply supported plate and a stiffened simply supported plate, are analyzed to demonstrate and validate the algorithms. Structural/acoustic sensitivity results are compared successfully to data computed by finite difference analyses.