A new sensitivity analysis scheme for coupled vibro-acoustic system using wave based method

Vibro-acoustic sensitivity is used to predict the change of structure displacement and acoustic pressure when the design variable has been changed, which is significant for reducing the vibration and noise of systems. The sensitivity of structure displacement and acoustic pressure with respect to design variables are formulated based on the proposed 3D coupled vibro-acoustic system model. The dynamic variables within the entire solution domain are approximated in terms of global wave functions, which are exact solutions of the homogeneous parts of the control equations and the particular solutions, which are exact solutions of the inhomogeneous control equations, so no discretization is needed and the functions are regular. Based on a 3D vibro-acoustic cavity example model, the validation of the method is proven, and the sensitivity of structure displacement and acoustic pressure with respect to thickness of the plate and exciting frequency are obtained.