Abstract: In order to solve the problem of poor heat dissipation characteristics of aero-engine main shaft bearings, a kind of hollow inner cooling outer ring structure is proposed, and a dynamic model of hollow inner cooling structure is established. The effects of heat transfer coefficient and temperature on heat dissipation and impact resistance of bearing outer ring are studied by fluid-thermosolid coupling analysis method. The influence mechanism of different working conditions on bearing temperature rise, deformation and damping ratio is explained, and the important influence of heat transfer coefficient and temperature of inner wall of outer ring on bearing performance is revealed. The results show that the higher the heat transfer coefficient and temperature of the inner surface of the outer ring, the greater the change of the overall temperature rise of the outer ring. The temperature change of the hollow channel inlet in the outer ring has little influence on the pressure change in the fluid domain. Under high temperature environment, the maximum deformation and maximum stress of the bearing become larger, and the high temperature environment can change the maximum deformation position of the bearing. When the temperature is low and the heat transfer coefficient is high, the damping of the outer ring is relatively large, which helps to reduce the vibration of the outer ring. The research results are of great significance to the optimal design of heat dissipation of main shaft bearings.

Key words: main shaft bearing, hollow internal cooling structure, heat resistance, temperature rise, damping ratio