基于多体系统动力学理论，综合考虑齿轮副时变啮合刚度、齿侧间隙、轴承刚度及阻尼、转速连续变化的影响，建立了变速器传动系统动力学模型，计算得到齿轮动态啮
合力和壳体各轴承座处的动态支反力． 然后对变速器壳体柔性化处理，获得变速器壳体固有频率及振型． 最后以各轴承座处的动态支反力为激励，采用模态叠加法计算壳体结构的动态响应，获得了壳体表面的振动信息． 仿真结果表明:在扭矩一定时，变速器壳体表面振动加速度幅值随转速升高呈增大趋势，与实验台架实测结果吻合良好，并且误差在 10%以内．

Based on the dynamic theory of the multi-body system,a dynamic model of a gear transmission system is constructed by taking into account the effects of the time-varying mesh stiffness，the tooth backlash,the bearing stiffness and damping，and the speed variation.Then，the dynamic meshing forces of gears and the dynamic forces of housing bearing seats are calculated,and after a flexible housing model is constructed，the natural frequency and modal shapes of the transmission housing are obtained.Finally,by taking the dynamic forces of the housing bearing seats as the excitation,the modal superposition method is adopted to calculate the dynamic response,thus acquiring the information relative to the vibration of the nodes on the housing surface.Simulation results show that,when a constant torque is applied,the vibration acceleration amplitude of the housing surface increases with the increase of the rotating speed,which accords well with the experimental results within a margin of error of 10%.