The dynamic model of the gear transmission system is built in consideration of the time-varying mesh stiffness and the gear errors. Then the time history of the dynamic load of system is obtained. The gear box structural-acoustic coupling system is built and calculated by using BEM. The noise spectrum of the gear box and the panel contribution are obtained. The effect of the gear box structure improvement, structure damping and different gear style on the noise radiation is analyzed. The study provides useful theoretical guideline to the design of the gear box.

The structural finite element model and soundstructure coupling boundary element model of a transmission box are established in this paper. The modal analysis of the structural finite element model is done. The soundstructure coupling boundary element model is solved by boundary element method (BEM). The distribution of noise in a particular frequency domain is analyzed. Based on modal acoustic contribution analysis (MACA), the identification and effective control of the main noise source of the transmission box are carried out. This work has a practical significance for research and development of this product.