润滑方式对球轴承润滑性能影响的数值研究

关键词:球轴承；喷油润滑；环下润滑；两相流场；数值模拟

关键词:  球轴承  喷油润滑  环下润滑  两相流场  数值模拟

Key words:  Ball bearing  Oil-jet lubrication  Under-race lubrication  Two phase flow field  Numerical simulation

摘要:

为合理选择高速球轴承润滑方案，优化润滑系统参数，针对SKF7210角接触球轴承建立了喷油润滑与环下润滑计算模型，基于VOF数值方法，研究了两种润滑方式下轴承内油气两相流场和内外环温度场。研究结果表明:相同工况下，环下润滑轴承内油气分布较喷油润滑更为均匀；转速增加两种润滑方式润滑效果均下降，但对环下润滑影响更大，当转速超过18kr/min时 (Q=3L/min， F=5kN)，环下润滑轴承内油体积分数将低于喷射润滑；供油量增加可改善润滑效果，尤其对环下润滑，当转速大于10kr/min时，环下润滑轴承内油体积分数相对喷油润滑将大幅提高；载荷增加会使轴承内油体积分数减小。结论:当转速和载荷较低时，可使用结构简单的喷油润滑；当转速和载荷较高时，使用环下润滑较为有利，但需保证供油量维持在较高水平。

Abstract:

In order to choose the lubrication scheme of high speed ball bearing reasonably，and optimize the lubrication system parameters，the calculation models of oil-jet lubrication and under-race lubrication for SKF7210 angular contact ball bearing were established. Based on the VOF method，the internal oil-gas two phase flow and the inner-outer ring temperature with the two different lubrication methods were studied. The results show that under the same working condition，the oil-gas distribution in the under-race lubrication bearing is more uniform than that of the oil-jet lubricating bearing. The lubrication effect of both lubrication modes decreases with the increase of rotating speed，and the effect on the under-race lubrication is greater. When the speed exceeds 18kr/min(Q=3L/min，F=5kN)，the oil volume fraction in the bearing of the under-race lubrication will be lower than that of the oil-jet lubrication. The increase of oil supply can improve the lubrication effect，especially for the under-race lubrication. When the speed is greater than 10kr/min，the oil volume fraction in the bearing of under-race lubriction will be greatly improved relative to the oil-jet lubrication. Increasing the load will reduce the internal oil volume fraction of the bearing. Conclusion: when the speed and the load are low，a simple oil-jet lubrication can be used，when the speed and the load are high，it is advantageous to use the under-race lubrication，but the oil supply should be maintained at a high level.