The Influence of the Raceway Curvature Ratio on Power Loss and Temperature of a High-Speed Jet Engine Ball Bearing

High-speed jet engine ball bearings operate under challenging operating conditions, such as high speeds, loads, and temperatures. In addition, they have to meet the highest reliability standards. Thus, they require advanced materials, designs, and cooling systems. Though new materials, heat treatments, and component designs have been developed to meet these challenging requirements, the design of the raceway curvature ratio mainly follows the classical rolling bearing life theory, which is based on subsurface fatigue. But the frictional heating in the contact zone due to the phenomenon of microsliding is not considered in the design of high-speed ball bearings. This article presents the results obtained from rig testing with a state-of-the-art high-speed jet engine ball bearing with various curvature ratios on the inner and outer races. The influence of the curvature ratio on the bearing ring temperatures and the bearing power loss is demonstrated.