Structural-Acoustic Modal Analysis and Synthesis
This chapter develops the modal series solution method to predict the interior sound pressure response in an enclosure with flexible and absorptive walls. It also explains the component mode synthesis (CMS) methodology to couple individual structural substructure models, and couple individual acoustic cavity models. The chapter considers the methodology that is commonly used in developing structural-acoustic models to predict the interior sound pressure response in transportation vehicle applications. It describes the theoretical formulation to develop the coupled structural-acoustic model from modal models of the structure and acoustic cavity. Then, it illustrates the application of the structural-acoustic methodology to simplified models (e.g. Helmholtz resonator model, flexible wall model). Finally, the use of matrix representation to develop the CMS technique is shown. The matrix representation is first applied to represent the coupled structural-acoustic modal model, and then to develop the CMS technique to couple multiple structural and multiple cavity modal models.
