基于应力云图和有限元的柴油机曲轴疲劳强度分析

Based on the stress cloud map and Ansys fatigue strength analysis diesel engine

柴油机在运转过程中受到剧烈的振动,会使轴系附件损坏,喷油、气阀定时遭到破坏,严重时会影响柴油机的平衡性,加剧柴油机的噪声,甚至会造成曲轴疲劳断裂。本文通过对船舶主机曲轴-轴系进行建模,采用曲轴三维整体模型,并在Ansys Workbench中进行预处理,对曲轴实体模型进行网格化分。再借助有限元软件Ansys进行受力分析,得出曲轴变形量和应力云图。最后对其进行疲劳强度分析,重点研究在气缸力、轴承支撑力以及推进轴系载荷三者作用下的曲轴疲劳强度。

The diesel engine is subjected to severe vibration during the operation,which will damage the accessories of the shaft,the fuel injection and valve timing,which will seriously affect the balance of diesel engine and aggravate the noise of the diesel engine.The strong vibration will cause the fatigue fracture of the crankshaft.In this paper,by modeling the crankshaft-shaft system of the ship’s main engine,by using the three-dimensional integral model of crankshaft and preprocessing in Ansys Workbench,meshing solid model of the crankshaft.The force analysis is carried out with the finite element software Ansys,obtaining the deformation and stress cloud map of the crankshaft.Finally,the fatigue strength of the crankshaft is carried out.Strength analysis is focused on the crankshaft fatigue strength under the three functions of cylinder force,bearing support force and propulsion shaft load.