Advanced Computational Dissipative Structural Acoustics and Fluid-Structure Interaction in Low- and Medium-Frequency Domains. Reduced-Order Models and Uncertainty Quantification

This paper presents an advanced computational method for the prediction of the responses in the frequency domain of general linear dissipative structural-acoustic and fluid-structure systems, in the low- and medium-frequency do-mains, including uncertainty quantification. The system under consideration is constituted of a deformable dissipative structure, coupled with an internal dissipative acoustic fluid including wall acoustic impedances and surrounded by an infinite acoustic fluid. The system is submitted to given internal and external acoustic sources and to prescribed mechanical forces. An efficient reduced-order computational model is constructed using a finite element discretization for the structure and the internal acoustic fluid. The external acoustic fluid is treated using an appropriate boundary element method in the frequency domain. All the required modeling aspects for the analysis of the medium-frequency domain have been introduced namely, a viscoelastic behavior for the structure, an appropriate dissipative model for the internal acoustic fluid including wall acoustic impedance and a model of uncertainty in particular for modeling errors. This advanced computational formulation, corresponding to new extensions and complements with respect to the state-of-the-art, is well adapted for developing new generation of software, in particular for parallel computers