喷嘴结构对角接触球轴承油气润滑中气帘效应的影响

Influences of Nozzle Structure on Air Curtain Effect in Oil-air Lubrication of Angular Contact Ball Bearings

针对角接触球轴承油气润滑中的气帘效应问题,基于气液两相流理论,构建了轴承腔内油气两相流的数值分析模型,分析了轴承腔内气帘效应的形成机理及影响因素,对比分析了5种喷嘴结构对气帘效应的影响。结果表明:在高速工况下,内圈与滚动体接触区附近产生的气帘效应阻止润滑油到达润滑点;气帘效应随轴承转速的升高而加剧;使用D型喷嘴结构时,气帘效应的影响最小,滚动体接触区附近油相的体积分数最大,轴承润滑效果最佳。

Aiming at air curtain effect in oil-air lubrication of high-speed angular contact ball bearings,a numerical analysis model of oil-air two-phase flow in bearing cavity was constructed,which was based on the theory of air-liquid two-phase flow.Formation mechanism and influencing factors of the air-curtain effect in bearing cavities were analyzed.Influences of 5 types of nozzles on the air curtain effect and oil-air two-phase flow were compared and analyzed.The results show that,under high-speed working conditions,air curtain effect occurs near the contact areas between inner ring and rolling elements,which prevents lubricating oil from reaching lubrication point.The air curtain effect will be intensified with the increase of bearing rotation speed.When the D type oil-air nozzles is used,the effects of air curtain on oil-air two-phase flow are minimal,volume fraction of oil phase is the biggest near the contact zones of inner ring and rolling elements,bearing lubrication is also the best.