轿车车内低频噪声声固耦合与灵敏度分析

o predict the low frequency noise of a domestic vehicle, a structural-acoustic coupling finite element model was established based on the BIW FE model which is verified by the experimental modal analysis results. The excitation signals at the suspension mountings, engine mountings and the respond signals of interior noise and vibration are measured under 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 20Hz 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. The sensitivity on each panel thickness of the vehicle was calculated. According to the directly guidance of the sensitivity results, the layout of damping layer on the firewall was modified, the interior noise of vehicle was reduced.