A Physics-Based Heat Transfer Analysis for Aerospace Ball Thrust Bearings

Abstract

Component temperatures have a significant influence on ball bearing life and durability. Critical parameters such as internal clearance, contact stress and oil film thickness are influenced by the thermal characteristics of a bearing. Previous heat transfer analyses that predict bearing ring temperatures have been typically based on empirical data. A new physics-based analysis has been developed which is derived from fundamental heat transfer and fluid flow equations. Gyroscopic torque and churning forces are balanced by oil shearing contact traction, using recent developments in new life theory [1] and lubricant property models [2]. Bearing ring temperatures and heat generation calculated by the new analysis have been successfully correlated with test data over a wide range of bearing sizes and operating conditions.