附加质量对变速器壳体模态的影响

时松青，徐传燕，慈长凯，邢其森

山东交通学院汽车工程学院，山东 济南   250357

摘要：为分析附加质量对变速器壳体模态的影响，以某微型汽车的变速器壳体为例，用传感器模拟变速器壳体的附加质量，设置7种模态试验方案，分析相同附加质量作用于不同测点、不同附加质量作用于相同测点及附加质量不同分布方式下变速器壳体固有频率的变化。采用模态置信度、模态相位共线性和平均相位偏移验证模态试验数据的有效性和可靠性。结果表明：变速器壳体厚度不均匀，不同测点下相同附加质量对壳体固有频率的影响不同，壳体薄壁处振型较大，固有频率较小；同一测点的附加质量越大，变速器壳体的固有频率越小；附加质量均匀分布于变速器壳体时，固有频率较小。在模态试验中,应优先考虑采用非接触式传感器及轻质传感器测试变速器壳体等薄壁构件，附加质量应均匀分布到结构中，并尽量避开振型节点和振型幅值较大区域。

关键词：变速器壳体；模态试验；附加质量；固有频率；模态影响

Influence of additional mass on transmission housing modal

SHI Songqing, XU Chuanyan, CI Changkai, XING Qisen

School of Automotive Engineering, Shandong Jiaotong University, Jinan 250357, China

Abstract:To analyze the influence of the additional mass on transmission housing modal, taking the transmission housing of a compact car as an example, the sensor is used to simulate the additional mass of the transmission housing, and seven modal test schemes are set up to analyze the changes of the intrinsic frequency of the transmission housing under the same additional mass acting on different measurement points, different additional masses acting on the same measurement points, and different additional mass distributions. The validity and reliability of the modal test data are verified by modal confidence criterion, modal phase collinearity and average phase offset. The results show that the thickness of the transmission housing is uneven, and the influence of the same additional mass acting on the different measurement points on the transmission housing modal is different. The modal shape at the thin wall of the transmission housing is larger, and the intrinsic frequency is smaller. The larger the additional mass at the same measurement point is, the smaller the intrinsic frequency of the transmission housing modal is. When the additional mass is evenly distributed in the transmission housing, the intrinsic frequency is small. For thin-walled structural parts such as transmission housings, preference should be given to non-contact sensor and lightweight sensor in the modal test, the additional mass should be evenly distributed into the structure, and the nodes and areas with large mode amplitude should be avoided as much as possible.

Keywords:transmission housing；modal test；additional mass；intrinsic frequency；modal influence