基于多轴疲劳理论的曲轴结构等效疲劳研究  

A Study on the Equivalent Fatigue of Crankshaft Structure Based on the Theory of Multi-axial Fatigue

作　　者：孙嵩松[1] 俞小莉[1] 李建锋 

机构地区：[1]浙江大学动力机械及车辆工程研究所,杭州310027 [2]潍柴动力杭州分公司,杭州310012

出　　处：《汽车工程》2016年第8期1001-1005,共5页Automotive Engineering

摘　　要：采用有限元法,对曲轴进行弯矩载荷作用下的应力分析,并应用坐标变换法对应力集中区域内的应力状态进行分析,确定曲轴的临界平面位置和疲劳损伤的类型。在此基础上选择合适的多轴疲劳损伤模型对由同种材料、不同结构的曲轴的疲劳极限载荷进行预测。预测与试验结果对比表明:传统的名义应力法在预测同种材料、且圆角半径相同的曲轴疲劳极限载荷时具有较高的准确度,但是在预测不同圆角的曲轴的疲劳极限载荷时,误差较大;而采用经典的KBM多轴疲劳损伤模型,能有效准确地预测不同圆角的曲轴的疲劳极限载荷。The stress analysis of a crankshaft under bending moment loading is conducted by using finite element method,and the stress states in its stress concentration area are analyzed by applying coordinate transformation scheme to determine the position of critical plane and the fatigue damage types of crankshaft. On this basis, an appropriate multi-axial fatigue damage model is chosen to predict the fatigue limit load of crankshafts with the same material and different structures. The results of comparison between prediction and test show that the traditional nominal stress method has higher accuracy in predicting the fatigue limit load of crankshafts with the same material and same fillet radius,but has relatively apparent error in predicting the fatigue limit load of crankshafts with different fillet radii,while the classical KBM multi-axial fatigue damage model can effectively and accurately predict the fatigue limit load of crankshafts with different fillet radii.

关 键 词：发动机曲轴 多轴疲劳损伤模型 临界平面 疲劳极限载荷 

分 类 号：U464.133.3[机械工程—车辆工程]