某MPV车型变速器异常振动噪声识别分析

Identification and Analysis of Abnormal Vibration and Noise of Transmission of a Certain MPV

对某在研MPV车型NVH性能测试中发现的变速器异常振动噪声进行声振测试及辨识分析,应用阶次分析对其故障特征进行辨识,探讨异常振动噪声的发生机理。基于Romax软件平台建立变速器的动力学分析模型,对其固有特性和动态响应特性进行分析,提出了一种变速器空载齿轮敲击的评价指标,以发动机气缸压力实测数据为输入,考察不同转速下空载齿轮敲击评价指标的变化。分析结果与试验数据吻合。

The method of order analysis based on noise and vibration tests was used to identify the abnormal vibration and noise sources of automobile transmission, and the mechanism of noise generation was also investigated. Based on the results, a precise dynamic model for transmission that caused the noise was established with Romax software, and the model was further validated based on experimental results. A novel evaluation index for gear rattle was proposed. The input excitation of gear rattle was acquired by calculating the output torque fluctuation of engine. The torque fluctuation was obtained by taking advantage of actual engine cylinder pressure under various engine speeds and the index for different speeds was discussed and verified. The analysis results agree with the experimental data.