Design optimization of acoustic radiation from structures under random excitation

Acoustic design optimization of structures subjected to random excitations is investigated in this paper. In this work, a Pseudo excitation method (PEM), an accurate and highly efficient algorithm series for structural stationary random response analysis, is extended to deal with random acoustic radiation problems. A boundary element method (BEM) and a finite element method (FEM) are combined with the PEM to calculate acoustic radiation from random excited structures. A design optimization model is presented, in which the pressure power spectral density (PSD), mass of the structure or eigenvalues of the structure is used as an objective function or constraint function. The thickness of the structure is used as a design variable. Based on acoustic radiation sensitivity analysis and structural sensitivity analysis, the design optimization model is solved with sequential linear programming. Numerical examples of sensitivity analysis and acoustic design optimization are given to demonstrate the effectiveness of the proposed method.