摩托车车架疲劳寿命对比分析及优化设计

The comparative analysis and optimization design of motorcycle frame fatigue life

摩托车车架可靠性决定了摩托车的使用寿命。基于MSC.Patran/Hypermesh有限元软件建立了摩托车整车动力学模型,考虑管状结构连接处特殊性,采用非均匀密度进行局部网格划分,结合实测路面随机激励、载荷及约束条件等,对车架结构关键位置进行疲劳寿命分析,并与改进后的结构疲劳寿命进行对比。结果表明:摩托车整车多体动力学模型精度高,车架疲劳薄弱位置预测合理,改进后的车架疲劳寿命明显提高。

The fatigue reliability of motorcycle frame determines the service life of motorcycle,affects the safety of motorcycle driving.It establishes the dynamic model of motorcycle based on finite element method,which considers the special connection of tubular structure and local mesh generation with non-uniform grid density,Combined with the random excitation,load and constraint conditions of the measured pavement,it analyzes the fatigue life of the key positions of the frame structure and the fatigue life of the improved structure.The results show that the multi-body dynamics model of the whole motorcycle has high precision,reasonable prediction of weak position of frame fatigue,the improved frame fatigue life effect is obvious.