客车排气系统振动特性优化及试验验证

为提高某国产轻型客车的乘坐舒适性，解决车内排气系统侧车身地板振动较大的问题，通过与对标车进行道路试验对比分析，发现排气系统吊挂点位置和吊挂悬置刚度的设计并不合理，导致排气系统向车身传递的振动过大。基于平均驱动自由度位移法（ADDOFD）分析计算，得到所有参考点的各阶模态振型加权求和，重新选择平均驱动自由度位移较小的位置作为排气系统吊挂点；综合考虑吊挂悬置隔振效果和耐疲劳性能，对吊挂悬置刚度进行优化设计。最后，对排气系统吊挂位置和吊挂悬置刚度优化设计提出最优改进方案，并进行试验验证分析，试验结果验证了该优化方案的有效性与合理性。

Optimization and Experimental Verification of Vibration Characteristics for a Light Bus Exhaust System

In order to improve the ride comfort of a domestic light bus, reduce the abnormal larger vibration of the body floor at Exhaust System side, the road test was carried out and compared with those of the competitive bus. The test results showed that the hanger locations layout and stiffness of the Exhaust System are unreasonable, causing the vibration of the vehicle body transferred from the Exhaust System is excessively large. the average driving DOF(ADDOFD) is applied to analysis, then summation of ADDOFD displacement response of reference points was calculated in range of all the modal-shapes, an optimized hanger locations layout was obtained on the basis of the minimum of the summation of ADDOFD displacement response; the hanger stiffness was optimized through comprehensive consideration of the vibration isolation and fatigue resistance characteristics. The optimal scheme was designed and test analysis was performed based on the optimization of the hanger locations layout and stiffness. Comparing the test results before and after optimization, the effectiveness and rationality of the optimization were verified.