定转速车内噪声的试验分析

Operating Analysis of Booming Noise of the Fixed Rpm of Engine

根据现有的车内噪声的研究资料,确定某车型定转速车内噪音主要影响因素是轰鸣声。通过试验进行传递路径分析,确定轰鸣声的传递路径。再使用敲击法试验确定发动机定转速与传动系上的长半轴产生共振,并进一步分析长半轴的振动响应和传递函数,提出使用动态减震器改变长半轴的模态,来减小振幅、错开共振点。Ⅲ档全油门加速噪声分析试验表明,在长半轴上安装动态减振器后,车内噪声水平得到明显改善。

It was confirmed that interior noise of the fixed rpm of engine is caused by booming noise, based on the literature datum of existing study on the interior noise. We make sure transfer path of the booming noise by testing. And we make sure the fixed rpm of engine produce sympathetic vibration with major driveshaft in power train by hammering test and analyze the vibration response and transfer function. Then we suggest that changing the major driveshaft＇s modal by using dynamic damper so as to decrease amplitude and avoid the resonance point. It was indicated that the level of interior noise was improved clearly by the analysis of the noise under full throttle acceleration in the 3rd gear after we assemble the dynamic damper in major driveshaft.