前副车架安装动力吸振器对加速车内噪声的改善

Improvement of Interior Noise during Acceleration with Dynamic Vibration Absorber Mounted to Front Sub-frame

通过整车状态下副车架约束模态和油门全开道路行驶工况下的噪声振动测试和分析,确定了车内"嗡嗡"声的根源(发动机二阶激励引起副车架共振传递至车内)及其频段。在此基础上,采用在前副车架的悬置安装点附近安装一个动力吸振器的方案,在此之前为了确定吸振器的质量,讨论了等效质量的两种理论计算方法及阻尼比的设定,试验表明,吸振器的应用有效地衰减了副车架在该频段的振动,从而减小了对副车架垂向弯曲模态的激励,基本上消除了车内的噪声峰值,显著改善了加速工况下的车内噪声。

Through sub-frame restrained mode and noise and vibration measurement under full vehicle at WOT on road respectively, the source of the interior booming （the engine 2nd excitation bring to the front sub-frame resonance and it transfers to interior vehicle） and its frequency section are determined. Based on these, a method is adopted that a dynamic vibration absorber is mounted on the front sub-frame with its frequency but with an opposite phase to counteract the vibration of it by a large margin in that frequency section. In order to confirm the DVA optimization mass, discuss two theories and computation methods and damping ratio＇s definition of it. Hence the excitation of sub-frame vibration on vertical bending mode is reduced and the resonance sub-frame is basically eliminated with the NVH characteristics of vehicle improved.