考虑磨损深度与弹性变形的船舶艉轴承润滑特性分析

Analysis of lubrication characteristics of ship stern bearing considering wear depth and elastic deformation

本文在分析偏心艉轴承润滑性能的基础上,建立艉轴承局部磨损和刚度的弹流耦合润滑模型,并编写有限差分法和有限元法联合程序求解轴承弹性变形,采用质量守恒边界条件代替雷诺边界条件,详细讨论局部磨损深度、轴承弹性模量等因素对轴承流体动压力、液膜厚度、空穴区域和摩擦力规律的影响。结果表明:刚体轴承局部磨损深度低于阈值时有益于轴承润滑,而超过阈值时对应的最大流体动压、摩擦力和空化区域将明显增加;轴承弹性形变对计算结果影响不可忽视,弹性形变和局部磨损同时存在,其变化规律与刚体轴承局部磨损变化趋势基本一致。

Based on the analysis of the lubrication performance of the eccentric stern bearing,an elasto-hydrodynamic coupling lubrication model for the local wear and stiffness of the stern bearing was established.The joint program of finite difference method and finite element method was compiled to solve the elastic deformation of the bearing,and the mass conservation boundary condition was used to replace the Reynolds boundary condition.The effects of local wear depth,bearing elastic modulus and other factors on the hydrodynamic pressure,liquid film thickness,cavitation area and friction law of the bearing were discussed in detail.The results show that when the local wear depth of rigid body bearing is lower than the threshold value,it is beneficial for bearing lubrication.When the local wear depth exceeds the threshold value,the maximum hydrodynamic pressure,friction force and cavitation area increase significantly.The influence of bearing elastic deformation on the calculation results cannot be ignored.Elastic deformation and local wear exist at the same time,and the change law is basically consistent with the change trend of local wear of rigid body bearings.