Analysis Of Temperature Field Of Bearing Assembly For Control Moment Gyroscope

The control momentum gyro is a critical attitude control component of spacecraft. With the development of space technology, the spacecraft is required to have more and more functions, while demands for the aircraft’s pointing accuracy and stability of the aircraft’s attitude also keep increasing, the control moment gyro becomes currently an important research direction. Bearing assembly is the core of the attitude control system equipment, which temperature distribution directly affects performance, life and reliability of the control moment gyro. The study of the bearing assembly’s temperature field in different conditions is able to provide a powerful basis for the design of the bearing, therefore, the analysis of bearing assembly’s temperature distribution become more and more important.In this paper, the finite element method and the heat balance method are used for solving the problem of temperature field in bearing assembly, considering the effect of the different conditions, environmental factors and motor power on the bearing assembly temperature field. Firstly, a dynamics model bearing, to give the desired force and motion parameters, in order to establish bearing friction bearing assembly power mathematical model, solving the main bearing friction power. Then, depending on the structural characteristics of the high-speed control moment gyro bearing assembly and the specific conditions, analyzing heat transfer mechanism and bearing assembly process, the use of steady-state thermal analysis module ANSYS Workbench, for a certain type of control moment gyros bearing assembly modeling, analysis study the different conditions, the temperature distribution and variation of ambient temperature and motor power bearing assembly.The results show that: 1 The total power consumption of the bearing is significantly increasing with operating speed and the axial load. But with the increasing of the radial load, the change of bearing’s the total power consumption is not obvious; 2 The maximum temperature of bearing assembly appears on the inner ring’s raceway of the high-speed bearing, the minimum temperature appears on the edge of flywheel, and the temperature of outer ring is lower than that of the inner ring; 3 Bearing’s operating speed, axial load have great impact on it’s temperature, while the radial load has not obvious effect on the temperature rise; 4 With the increase of the ambient temperature and motor power, the temperature rise is obvious; 5 The tests show that the finite element analysis and heat balance method of network are reliable; 6 According to the results of experimental tests, the temperature distribution by FEM method is better than that by the traditional network heat balance method.