基于传递路径分析的动力传动系统NVH性能匹配研究

A Research on the Matching of Power-train NVH Performance Based on Transfer Path Analysis

本文中对前置后驱汽车动力传动系统激振力的分配和传递路径进行了研究。通过在整车刚柔耦合模型上施加动力传动系统激振力,提取车辆关键硬点载荷并据此进行NVH性能的传递路径分析,从而对动力传动系统的主要参数进行匹配。针对某搭载四缸发动机前置后驱微车车内中低频轰鸣噪声问题,采用多体动力学方法和有限元法建立整车刚柔耦合模型,并通过K&C试验和动态载荷试验验证了模型的准确性后,计算该车型在3挡全油门工况下的关键硬点载荷。根据噪声传递路径分析结果对动力传动系统参数进行匹配优化。试验结果表明,优化匹配后车内噪声明显下降,有效解决了中低频轰鸣问题。

The distribution and transfer path of excitation forces in the power-train system of a front-engine rear-drive vehicle are studied in this paper. By applying the excitation forces in power-train on the vehicle rigid- flex-ible coupled model,the key hard-point loads of vehicle are extracted,a transfer path analysis （TPA） on its NVH performance is conducted, and hence an optimal matching on the major parameters of power-train system is per-formed. Then aiming at the low-medium frequency roar problem in a front 4-cyinder engine rear-drive mini- vehicle, a rigid-flexible coupled vehicle model is created by multi-body dynamics and finite element method, and after the correctness of the model is verified by K＆C test and dynamic loading test, the loads at key hard-points of the vehicle at WOT and third gear condition are calculated,and an optimal matching on power-train parameters is proceeded based on the results of TPA. The results of test show that after optimal matching the interior noise obviously lowers, effectively solving the problem of low-medium frequency roar.