Analysis and control of structure-borne noise for a trimmed body by using panel acoustic participation method

摘要

This paper is aimed to analyze and control the structure-borne noise of a trimmed body (TB) under excitation by three engine mounts using panel acoustic participation (PAP) method. For each TB panel, the acoustic frequency response function is applied to obtain critical frequencies of interest under each excitation. The PAP analysis is then carried out at all critical frequencies. Panels of acoustic significance are identified by the correlation coefficient matrix (CCM) method for all excitations. The acoustic contributions from those panels may be positive or negative. It is found the control of the total interior noise level can be achieved by suppressing the vibration of positive contribution panels or by increasing the vibration of negative contribution panels. It is verified by installing dynamic vibration absorbers at selected positions on the positive contribution panel to reduce the vibration to control noise level and on the negative contribution panel to reduce the vibration to increase noise level. The PAP method is also compared with the other methods such as the operational deflection shape (ODS) analysis and the structural vibration modal analysis. It is concluded that the PAP method is more effective to control the structure-borne noise.