Abstract: The interior low frequency noise of passenger car has direct influence on its comfort. An attempt at applying the finite element method and modal test technique to the measurement and analysis on the vehicle body vibration and its interior noise is made,and the analysis conclusion is consistent with test result in low frequencies.By using the theory of coupling structural—acoustic system, a series ofresearches are carried out and some conclusion are drawn which could be very useful for the modification of the structural and acoustic for the vehicle reducing passenger compartment noise level especially at low frequencies.

Key words: Coupling, Noise, Structure, Vibration