船用柴油机曲轴主轴承润滑性能数值分析

Research on lubrication performance of main bearingin a marine diesel engine

曲轴主轴承工作性能好坏对柴油机性能产生直接影响作用。本文建立某型船用柴油机曲轴主轴承润滑特性数值分析模型,对不同转速工况下主轴承润滑特性进行分析,获得了一个工作循环内的载荷、油膜压力、油膜厚度及轴心轨迹等润滑性能参数。经分析表明,第5主轴承润滑性能相对最差,这主要是由于柴油机曲轴在载荷作用下发生一定程度的弯曲变形,造成第5主轴承下轴瓦中部处的油膜厚度相对较薄,且存在发生过度磨损的隐患。本文研究工作可为船用柴油机曲轴主轴承的设计与优化提供参考。

The performance of crankshaft main bearing has a direct effect on the performance of diesel engine.In this paper,a marine diesel engine was studied and the lubrication numerical model of main bearing was built.Numerical analysis was carried out on the lubrication performance of main bearings under different rotating speed conditions,and the stress distribution,the maximum oil film pressure,the minimum oil film thickness,the axis orbit and other lubrication performance parameters were obtained.The results show that the tilt of journal results in the reducing of oil film thickness on central of lower bearing in fifth main bearing,which also leads to serious wear.The research in the paper provides a reference for the optimal design of marine diesel engine.