Interior Noise Reduction of a Mini-Bus Using Panel Contribution Analysis

Numerical and experimental methods are applied effectively to reduce the interior noise of a mini-bus. In the frequency range where the booming noise occurs, acoustic forced response analysis is carried out, where experimentally measured vibrations of the floor by excitation test are used as boundary conditions. Through this analysis, the panels having positive effects to the interior noise are identified and confirmed through vehicle test. Then the coupling between the floor panels and the interior acoustic field is considered and the coupled acoustic field is analyzed by Boundary Element Method(BEM). As the result, the interior noise level of the bus is reduced effectively by structural modifications of the panels.