汽车动力总成悬置系统隔振性能仿真方法

摘要

The properties of vehicle’s noise vibration harshness(NVH) was affected by the vibra-tion isolation of powertrain mount system .Using the mechanism of vibration isolation to conclude the vibration transmitting rate expression which was defined by RMS ;based on the mechanism of double layer vibration isolation ,a 6-DOF model of a powertrain mounting system and a 12-DOF full vehicle model including the car frame were built respectively ,the inherent characteristics and frequency re-sponse of the two models were compared by the simulation analysis ;and under the idling conditions , acceleration response of the powertrain mounting system was studied;the vibration transmitting rate curve of the mounting points was obtained eventually .The results show that the full vehicle model can response the vibration characteristics of a powertrain mounting model and get the vehicle’s vibration i-solation transmitting rate at the same time .%针对动力总成悬置系统隔振性能的优劣影响整车的NVH特性，应用隔振原理，给出了由加速度均方根值定义的系统隔振传递率表达式；基于双层隔振机理，分别建立了动力总成6自由度悬置模型和包括车架的12自由度整车模型，并通过仿真分析比较了两种模型的固有特性和频域响应；在怠速工况下研究了悬置软垫处的加速度响应；最终获得各悬置点的隔振传递率曲线。研究结果表明，整车模型能够反应悬置系统的振动特性及其隔振传递率。