基于轮胎六分力的某商用车车架疲劳分析

实验以某重型商用车车架为研究对象，在汽车的3个车轴上共安装6个六分力仪，并在定远试验场多种路况下进行实车测试，获得车轮轮心处六分力。在HyperMesh中对车架进行有限元建模并应用惯性释放理论获得车架的单位载荷应力场分布。在ADAMS中建立整车刚柔耦合动力学模型，并将实车测试获得的轮心六分力导入模型中进行仿真，求得车架与悬架接附处的载荷谱。结合车架单位载荷应力场分布、车架与悬架接附处的载荷谱及车架材料的应变（ε）-疲劳寿命（N）曲线，根据线性累积损伤理论，使用nCode软件对车架进行疲劳仿真分析，分析结果表明该车架可靠寿命符合国家相关安全规定，满足设计要求。该仿真结果也被试验所验证。

Fatigue Analysis of Commercial Vehicle Frames Based on Six-dimensional Wheel Loads

A frame of a commercial vehicle was taken as the research object, and six-dimensional force transducers were fixed on the three axles of the vehicle. Tests were completed at Dingyuan test field with several typical roads to get six-dimensional force. The finite element model of the frame was built by HyperMesh and the stress field of the frame under unit load was obtained by using the inertia release theory. Rigid-flexible coupled multi-body dynamics model of the vehicle was built by ADAMS and the load spectrums of the junctions between frame and suspensions were obtained based on the six-dimensional force signals of the wheel hub. According to the linear cumulative damage theory, combining the stress distribution under unit load of the frame, the load spectrums of the junctions between the frame and the suspensions and the strain(ε)-fatigue life(N) curve of materials of the frame, fatigue simulations of the frame were carried out by nCode and the results show that the reliable life of the frame meets the relevant national safety regulations and the design requirements.  The simulation results are also verified by experiments.