Abstract: The flywheels in a satellite attitude control system usually use a pair of oillubricated precise angular-contact ball bearings as the rotary support. Because of the requirements for long life, high precision and high reliability of flywheels and special space environment, the lubrication of bearings uses microquantity oil. Either overflooded lubrication or starved lubrication can result in the increase of friction torque and decrease of the life of flywheel bearing. So there exists an optimum quantity of lubricating oil. We give a method to estimate the optimum quantity of lubricating oil in the flywheel bearing based on the elastohydrodynamic lubrication (EHL) theory. Meanwhile, a ballondisk test is developed to simulate the bearing ball and raceway contact. The experimental results verify the validity of the proposed method.

Key words: flywheel bearing, EHL, optimum lubricating oil quantity, ball-on-disk test