超高速轴承曲面兜孔复杂边界微间隙内润滑与摩擦特性研究

Friction and wear failure of bearing cage pocket due to its poor lubrication is the mainly failure form of ultra high speed rolling bearing. The lubrication performance and frictional behavior of bearing cage becomes the bottleneck which restricts the development of the ultra high speed bearing technology. The project focuses on the relative technology of bearing cage lubrication, which is urgent needed to raise the rotating speed of the domestic rolling bearing. A systematic research on the lubrication performance and frictional behavior inside the micro-clearance between the bearing pockets and roller in complicated boundary condition would conduct via this project. Firstly, the numerical model for lubrication analysis inside curved micro-clearance would be set up. The oil-air flow pattern and the lubrication parameters of the micro-clearance with complicated boundary can be investigated. Then the kinetic model of ultra high speed rolling bearing would be founded without the raceway control hypothesis, and the contact and friction behavior between the cage pocket and the roller can be calculated. Finally, based on the real contact and motion state inside rolling bearing, the lubrication performance and frictional behavior inside the micro-clearance between the bearing pockets and roller in complicated boundary condition would be theoretically analyzed. The mechanism of lubrication performance and the friction between cage pocket and the roller would be discussed and used for the optimum of cage pocket structure. Therefore, the aim of better lubrication and smaller frictional heat of ultra high speed rolling bearing would be approached. The conclusion of this project would make significant effect on the improvement of cage pocket lubrication performance, which would also break the cage temperature rising bottleneck of ultra high speed rolling bearing.

保持架兜孔润滑不良导致的摩擦磨损是超高速滚动轴承最主要的失效形式，成为制约超高速轴承技术发展的瓶颈。针对国产滚动轴承高速化对保持架润滑及减磨相关技术的迫切需求，拟系统研究超高速滚动轴承保持架曲面兜孔微小间隙内的润滑状态及摩擦行为。建立曲面兜孔微间隙润滑分析模型，研究复杂边界微间隙内油气两相流型及相关润滑参数；去除滚道控制假设，建立超高速滚动轴承动力学模型，分析保持架兜孔与钢球间的碰撞接触及摩擦力特征；基于轴承内部真实接触及运动状态，系统分析超高速条件下滚动轴承兜孔微间隙内的油气润滑及摩擦发热特性，探究其内部真实润滑状态及影响因素，揭示不同曲面兜孔微间隙内的润滑与摩擦发热机理，实现保持架兜孔良好润滑，降低摩擦发热。研究成果对于改善保持架兜孔润滑性能、突破超高速滚动轴承保持架摩擦温升瓶颈有重要意义。

高速化是滚动轴承技术发展的必然趋势，而保持架热特性是制约轴承高速性能的关键因素。项目选题瞄准国产滚动轴承高速化对保持架热分析与润滑技术的迫切需求，开展了高速轴承保持架运动与生热机理、保持架运行热特性在线监测研究工作，构建了基于拟动力学的五自由度高速角接触球轴承服役性能分析模型，理论分析了高速轴承保持架热特性，在此基础上提出了基于量子点传感器的高速轴承保持架温度监测技术，首次实现了转速10000r/min条件下的高速轴承保持架温度监测（目前国外保持架温度监测速度不超过1550r/min），为保持架生热分析提供了直接的实验数据。.在保持架生热特性机理研究的基础上，项目进一步研究了不同工况、不同结构参数下保持架的润滑性能。考虑高速球轴承服役中保持架散热特性，从保持架引导间隙、兜孔间隙的油气两相流动分析出发，提出了考虑工况的滚动轴承内部复杂边界条件下的油气两相计算方法，并基于场协同理论评估了高速轴承保持架关键接触区域的流动与换热性能。此外，从PIV可视化实验角度提出了高速轴承内部油气两相流动监测技术，开展了轴承内部流动与润滑状态实验监测，研究了真实工况环境下的轴承内部油气两相流动特点，揭示了保持架不同结构对于轴承内部流动及油气分布的影响规律，优化了保持架结构参数。.按照研究计划，圆满完成了项目的预期研究任务。项目主持人受邀在2017年国家滚动轴承产业技术创新联盟年会、2016年开元轴承高峰论坛、GAF2017轴承技术发展论坛等学术研讨会中做专题报告。项目研究成果用于洛阳轴研科技股份有限公司研发的高速轴承产品，获得了2017年中国机械工业科学技术二等奖。.基于项目研究工作，项目研究成员在国内外重要学术期刊和会议上发表论文11篇，其中SCI论文8篇(其中JCR一区1篇，二区5篇，录用1篇)；参编英文学术专著1章，参编中国轴协高端轴承技术路线图；申请发明专利5项；毕业硕士研究生5名，5人次获研究生国家奖学金；项目主持人获陕西省高校杰出青年人才、加拿大魁北克省政府国际优秀博士后等。