Development of eigenmode and frequency response sensitivity analysis methods for coupled acoustic-structural systems

Sensitivity analysis methods applicable to the eigenmodes and frequency responses of coupled acoustic-structural systems are proposed for the purpose of reducing vehicle interior noise. The concept of the left and right eigenvectors is introduced for treating coupled acoustic-structural problems, and four propositions concerning this concept are presented and proven. Based on these propositions, formulations are derived for conducting modal sensitivity and modal frequency response sensitivity analyses. The theoretical results and computation equations are verified through the application of the methods to a coupled acoustic-box structure and a practical vehicle interior noise problem.