Abstract: The structure finite element model is verified by the modal test of vehicle body in white in frequency domain and also by Modal Assurance Criterion; The engine mounts are chosen as the force impact points and then the structure vibration responses, which function as the boundary condition of the acoustic boundary element model, are acquired through the mode superposition method. Then the acoustic response of the certain position in vehicle cavity is calculated. According to the test results of actual SPL and the vibration responses of the engine mounts in idling condition, panel contribution analysis method is used to identify the panel with significant contribution, which serves as the basis to determine the position of damp treatment. The validation test of damp treatment shows a great decrease of peak value of the SPL.

Key words: Acoustic contribution, Acoustic senstivity, Acoustics, Damp, Modal assurance criterion, Mode, Mode superposition