发动机曲轴阶梯形圆角结构优选  

Optimization of Stepped Fillet Structure of Engine Crankshaft

作　　者：陈洋 CHEN Yang(Nanchong Agricultural Machinery Science Research Institute,Nanchong 637000,Sichuan,China)

机构地区：[1]南充市农业机械科学研究所,四川南充637000

出　　处：《机械研究与应用》2024年第4期138-141,共4页Mechanical Research & Application

摘　　要：当发动机曲轴受到周期性的循环载荷影响时,曲柄销圆角处会产生过大的应力而易引起疲劳裂纹。为了降低曲柄销圆角处的应力并提高曲轴的疲劳寿命,设计优化阶梯形圆角来降低曲柄销圆角应力。文章先对曲柄连杆进行多柔体动力学仿真,得到曲柄销处的载荷谱;然后基于RSM(Response Surface Methodology)建立以曲柄销圆角应力最小为优化目标,以R 1、R 2、H为设计因子的优化模型,并对优化模型进行求解。通过优化模型的对比分析发现,阶梯形圆角可以有效地降低曲柄销圆角处的应力值,减小了圆角处因应力过大而过早产生疲劳失效的可能性,所研究内容对曲轴圆角结构设计具有一定参考价值。Owing to the periodic cyclic load in the engine crankshaft,the crank pin will produce excessive Mises stress and further cause fatigue cracks.In order to decrease the Mises stress and improve the fatigue life of the crank pin,the crank pin stepped fillet will be designed and optimized in this article.Firstly,the flexible mulit-body dynamics simulation on the crank connecting rod is conducted in order to obtain the load spectrum of the crank pin.Then,the optimization model taking the minimum stress of the crank pin as the optimization objective and the value of R 1、R 2 and H as the design variables is built based on RSM(response surface methodology);and the optimization model is solved.It is concluded through comparative analysis on the optimization model that the stepped fillet can effectively reduce the Mises stress on the crank pin,and can reduce the possibility of premature fatigue failure due to excessive stress at the fillet.It has certain reference value to the structure design of crankshaft fillet.

关 键 词：曲轴 圆角应力 阶梯形 响应面法 

分 类 号：TK413.3[动力工程及工程热物理—动力机械及工程]