基于传递函数的发动机附件振动预测  

Engine Accessory Vibration Forecast Based on Transfer Function

作　　者：刘丹[1,2] 王辉[1,2] 宋兆哲[1,2] 杨景玲[1,2] 

机构地区：[1]长城汽车股份有限公司技术中心,河北保定071000 [2]河北省汽车工程技术研究中心,河北保定071000

出　　处：《噪声与振动控制》2016年第3期147-150,共4页Noise and Vibration Control

摘　　要：阐述整车异常振动噪声的排查过程,确定问题为发电机和空调压缩机组件1阶共振。通过模态试验和有限元分析结果对比,保证仿真模型准确性,为下一步传递函数分析提供输入。通过测试第三主轴承盖到空压机远端处传递函数,得到结构阻尼信息。采用相同阻尼值,对空调压缩机支架更改前后传递函数进行对比,改进后第1阶模态共振频率提高,同时幅值也有降低。对改进后样件进行整车试验,结果表明,在默认激励保持不变基础上,可通过传递函数来间接反应最终响应结果,从而验证可以利用传递函数对发动机外附件振动进行预测。The abnormal vibration and noise of a car is found to be caused by the first resonance of the alternator andair compressor. The finite element model of the system is established and its modals are simulated. Accuracy of the finiteelement model is verified by comparing the results of simulation with those of modal testing. Then, the results are used asthe input for transfer function analysis. The modal damping is got by testing the transfer function from the third main bearingcap to the far end of the air compressor. With the same damping value, the transfer functions before and after theimprovement of the air compressor bracket are mutually compared. The results show that the first order modal frequencyincreases and the amplitude decreases after the improvement. The vehicle with the improved bracket is tested. The resultsdemonstrate that the response can be represented by the transfer function when the engine excitation keeps invariable. Thus,transfer function can be used to forecast the engine accessory vibration.

关 键 词：振动与波 振动预测 传递函数 外附件 模态试验 

分 类 号：TB533.2[理学—物理]