Numerical Investigation of the Heat-Fluid Characteristic inside High-Speed Angular Contact Ball Bearing Lubricated with Grease

Abstract

The development of special grease makes it possible for angular contact ball bearings to operate at high speed and temperature, so, it become necessary to investigate thermal-fluid characteristics inside high-speed angular contact ball bearing lubricated with grease. In this paper, a simulation model for angular contact ball bearing was established with CFD software Fluent, the heat-fluid-solid coupling method was used to analyze the distribution and flow of grease, heat transfer, and temperature field inside the bearing chamber. The results show that, grease distribution inside bearing chamber was very inhomogeneous, most of grease was distributed on the both sides of the rolling elements along outer raceway and its flow velocity was very low, only a little grease was adhered on the surface of roll-ing elements, cage, and inner ring, its flow velocity was high; grease distribution inside bearing chamber becomes more inhomoge-neous with the increase of bearing speed; in bearing heat transfer conduction was dom-inant and grease plays a key role, convec-tion of air and grease was insignificant; affected by heat transfer condition the temperature rise of bearing components was obviously different, rolling elements have the highest temperature, the tempera-ture of inner ring was slightly lower than that of rolling elements, temperature of outer ring was the lowest. Bearing tempera-ture experiment was conducted on self-made test rig and verified the validity and accuracy of numerical simulation. The results of this study will provide some reference for lubrication design and thermal analysis of high speed angular contact ball bearing lubricated with grease.