Abstract:The dynamic response of the gear box is researched in consideration of the time-varying mesh stiffness and gear errors. The dynamic response model is set up and solved by using mode superposition method. Then the time history of node displacement of the gear box is obtained, and the effect of the excitation of frequency doubling of mesh frequency on dynamic response of the gear box is researched. Structural-acoustic coupling noise response analysis is done. The improving plan of the gear box is propound based on contribution of the gear box panels to noise radiation. The study provides useful theoretical guideline to the design of the gear box