实测道路载荷谱在新开发车型车身疲劳分析中的应用

根据新研发车和现有车型具有相同底盘平台的特点,提出一种利用现车道路载荷,快速进行新车车身疲劳分析和评估的方法。建立新车多体模型,放大现车道路载荷并结合轮胎接地位移为输入。根据车轮力传感器(WFT)载荷测量特点,正确地对模型加载激励,仿真得到车身载荷谱。选用合理疲劳分析方法预测车身寿命,以现车车身的疲劳分析损伤为目标,对不合格局部进行合理优化,最终新车车身达到设计耐久目标。

Application of measured road load spectrum in fatigue life Analysis of newly-developed-vehicle body frame

According to the characteristic of the same chassis adopted by both the newly developed vehicle model and the existing one,a method of quickly performing fatigue analysis and durability assessment for the new vehicle body structure was proposed based on the road loads of the existing vehicle.A multi-body dynamic model of the new vehicle was established,in which the scaled road loads and the tire patch displacement were used as input.The new-vehicle model was loaded and excited based on the characteristic of wheel force transducer(WFT)load measurement.The load spectrum was obtained by simulation and a fatigue analysis method was selected to predict the fatigue life of vehicle body.Taking the fatigue damage as the optimization target,the car body was modified and finally the new vehicle body met the requirements for durability.