Investigation of air flow pattern and heat transfer efficiency inside cavity of high-speed angular contact ball bearing

When a bearing operates at high speed, the high pressure region around the ball-raceway contact zone prevents the lubricant to enter the bearing cavity, resulting in a decrease of oil supply efficiency. To investigate the air phase flow pattern inside bearing cavity for the optimization of oil-air two-phase lubrication method, a high precision numerical model of air phase flow pattern inside angular contact ball bearing cavity is proposed. Comprehensive factors, including bearing motion features and cage structure, are considered to investigate their influences on the air phase flow pattern. Results show that the ball rotation leads to uneven pressure distributions. The air phase velocity, pressure, and heat transfer efficiency of cage increase when the ball revolving speed increases. The position near the inner ring on the bigger axial side is the ideal position to mount the lubrication unit. The heat transfer efficiency of cage and pressure field are sensitive to the cage structure. When the cage pocket clearance increases, the heat transfer efficiency of cage increases.