汽车排气系统吊钩位置优化

Hook Position Optimization of Automobile Exhaust System

在发动机和路面的激励下,排气系统振动和噪声传递给车身,将产生整车的振动噪声。这将严重影响车辆的NVH(Vibration振动、Noise噪声、Harshness平顺性)性能。运用ADDOFD(平均驱动自由度位移法)方法对排气系统吊钩位置进行了优化。首先根据已有的排气系统建立有限元模型,分别用仿真和试验的方法对排气系统进行模态分析,利用实验模态对有限元模态进行验证。最后在有效排气系统有限元模型的基础上利用ADDOFD(平均驱动自由度位移法)方法优化了吊钩的位置。结果显示优化吊钩位置后明显改善了整车的振动,证明原吊钩位置并不是最优位置。该方法可以有效地在早期车辆开发过程中选择较好的NVH性能悬挂架位置。

Under the excitation of the engine and the road surface,the vibration and noise of the exhaust system are transmitted to the body,which will produce the vibration noise of the whole vehicle.This will seriously affect the NVH(Vibration,Noise,Harshness)performance of the vehicle.The position of the hook is optimized by ADDOFD(average driving degree of freedom displacement method).Firstly,the finite element model of the exhaust system is established according to the existing exhaust system,and the modal analysis of the exhaust system is carried out respectively by simulation and experiment,and the finite element model is verified by experimental mode.Finally,based on the finite element model of the effective exhaust system,the position of the hook is optimized by the ADDOFD method.The results show that the vibration of the vehicle is obviously improved after optimizing the hook position,which proves that the original hook position is not the optimal position.This method can effectively select the better position of NVH performance suspension in early vehicle development.