Abstract: Based on the principle of bearing similar modes with vehicle, the simplified FE model of a heavy commercial vehicle cab is built. A structure-acoustic coupling model of the cab is built with the FE model, and it is validated with an acoustic modal test. The excitation signals at cab mounting and the respond signals of interior noise and vibration are measured under idling condition and even-speed driving condition with road testing. Appling the excitation signals to the structure-acoustic coupling model, the frequency response analysis is carried out and the interior structure noise between 20 Hz and 200 Hz is calculated. The simulated response of vibration and noise is compared with the result of testing. It is shown that the frequency spectrum of simulated response can express the effect of excitation spectrum and acoustic modes, and it coincides with the testing result. It can reach high accuracy to predict the level of interior noise and vibration with the structure-acoustic coupling model. To predict the level of interior noise and vibration by using this model can reach high precision.

Key words: Acoustic mod, Frequency spectrum, Interior noise, Response analysis, Structure noise, Structure-acoustic coupling