| 摘要:针对某船用多缸发动机的曲轴过渡圆角，进行三维动态疲劳强度分析及参数研究。建立整机刚柔耦合的动力学模型，获得曲轴在不同转角下的位移时间历程。建立各曲拐的有限元模型及过渡圆角的子模型，采用单位载荷法，得到圆角处的应力分布。根据单位载荷下的应力分布和位移时间历程，考察曲拐圆角的动态疲劳安全特性。研究发火顺序、圆角参数对曲轴的动态疲劳特性的影响。结果表明：合理的发火顺序可以优化曲轴的载荷分布，增加圆角尺寸可提高曲轴局部疲劳强度。 |
| 关键词: 曲轴 圆角 应力 疲劳强度 |
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| Dynamic Fatigue Analysis and Influencing Factors of Crankshaft Fillets |
| KANG Naxin,LI Wenda,NIU Junjun |
| China Shipbuilding Power Research Institute Co.， Ltd.， Shanghai 200129，China |
| Abstract:Three-dimensional dynamic fatigue strength analysis and parameter study were conducted on the crankshaft transition fillet of a certain marine multi-cylinder engine.The dynamic model of the whole engine with rigid flexible coupling was established， and the displacement time history of the crankshaft at different angles was obtained. Finite element models for each curve and sub models for transition fillets were established，and the unit load method was used to obtain the stress distribution at the corners. Based on the stress distribution and displacement time history under unit load， the dynamic fatigue safety characteristics of curved fillets were investigated. The influence of firing sequence and fillet parameters on the dynamic fatigue characteristics of crankshafts was studied.The results indicate that a reasonable firing sequence can optimize the load distribution of the crankshaft，and increasing the fillet size can improve the local fatigue strength of the crankshaft. |
| Key words: crankshaft fillet stress fatigue strength |
