Optimization Design Analysis of Automobile Powertrain Mount 2019-01-0540
Powertrain mount system plays a key role in the vibration isolation and vehicle comfort of the powertrain. It is of great academic and practical value to optimize the parameters of mount system. At present, most of the optimal design of the mount system adopts the 6-dof model. With the requirements of the 6-order rigid body mode of the Powertrain Mount system, stiffness in the linear segment, mounting position and mounting orientation of each mount are optimized. The optimal design method of automobile powertrain mount system is mainly limited to the design and optimization of the Mounting subsystem. There is little research on the overall optimization considering the excitation characteristics of the powertrain, the transmission path of vibration noise and the vibration noise inside the vehicle. Based on the multi-objective optimization theory, a 13-DOF optimal design model of automotive powertrain mount system is established in this paper. Setting the minimum of vertical vibration of driver seat guideway and the noise of driver's right ear, the maximum of system's vibration isolation rate and the energy decoupling rate, the reasonable allocation of system natural frequencies as the optimization targets, with the ratio of the three-direction and the lower bound of static stiffness as constraints, Genetic algorithm is used to optimize analysis. The results show that decoupling rate and the reasonable allocation of natural frequency of powertrain has great influence on the overall ride comfort of the vehicle, and the overall comfort of the vehicle has been greatly improved after multi-objective optimization.