低速行驶哨音问题的原因分析与解决

Cause Analysis and Solution of Low-Speed Driving Whistle Problem

针对某在研车型出现的低速行驶车内哨音问题,文章阐述了变速器激励原理及阶次激励特征,结合测试信号滤波回放方法及振动传递链上零部件模态测试排查,锁定哨音问题激励源为变速器,传递路径上摆臂刚度偏低,模态频率处振动衰减能力弱,放大激励引发问题。运用CAE分析工具制定摆臂加强方案,实车验证摆臂模态未发生变化,但刚度提升一倍,同等激励条件下摆臂响应幅值下降一倍,哨音问题主观感受、客观数据均改善明显,该方案具备工程化实施条件,最终问题得以解决。

Focusing on the whistling problem of a new vehicle by low speed,this paper expounds the excitation principle and order excitation characteristics of the transmission.The test signal filtering playback method combined with the modal test of the parts on the vibration transfer chain showed that the excitation source of the whistling problem is the transmission.The problem was caused by vibration of excitation amplified because of the stiffness of the low control arm on the transfer path is low and the vibration attenuation ability at the modal frequency is weak.The CAE analysis tool was used to formulate the strengthening scheme of the low control arm.It was verified that the mode of the low control arm did not change,but the stiffness was doubled,the response amplitude of the low control arm was decreased by twice under the same excitation conditions.Finally the problem was solved that the subjective feeling and objective data of the whistle problem were significantly improved,In addition the scheme had the engineering implementation conditions.