Effect Of The Guide Way Of Angular Contact Ball Bearing Cage On Its Motion And Oil-air Lubricated Two-phase Flow

As an important component of rolling bearing,cage has many ways to guide in practice.The motion of cage and the distribution of oil-air two-phase flow under different guiding modes have great influence on the working performance of bearing.Therefore,it is of great significance to study the motion characteristics of cage under different guiding modes and the influence on the oil-air two-phase flow in the bearing cavity.Based on Hertz contact theory,bearing dynamics,elastohydrodynamic lubrication,and computational fluid dynamics,and taking 7005 C angular contact ball bearings as the research object,the dynamic analysis model and fluid of angular contact ball bearings under different guiding methods of the cage are established.The calculation model analyzes and calculates the influence of the cage's different guiding methods on the cage's motion characteristics and the cage's different guiding methods on the pressure,the oil-air two-phase flow pattern and the temperature in the bearing cavity.The main conclusions are as follows:(1)The cage slip mainly occurs in the initial acceleration stage of angular contact ball bearings,and the cage slip rate is the lowest when the bearings run stably.When the rolling body guides the cage,the cage slip rate is the highest,followed by the outer ring guide cage slip rate,and the inner ring guide cage slip rate is the lowest.When the speed reaches 12000r/min,the trajectory of the mass center of cage is basically in a stable state.Compared with the cage centroid trajectory of the three cage guidance methods,the rolling element guides the cage's centroid trajectory at the same rotation speed,followed by the outer ring guide and the inner ring guides the cage's centroid trajectory.(2)Under different guiding methods of the cage,the overall air pressure threshold in the bearing cavity expands with the increase of the rotation speed,and the unevenness of the pressure distribution increases.When the outer ring guides the cage,the unevenness of the air pressure distribution in the bearing cavity is the largest.When the rolling element is guided and the inner ring is guided,the span of the air pressure extreme value in the bearing cavity is relatively small,and the unevenness of the air pressure distribution is small.In the outer ring guidance mode,the air pressure value near the contact area of the steel ball and the inner ring raceway is the largest,followed by the rolling element guidance,and the inner ring guidance air pressure value is the smallest.The air pressure value near the contact area of the outer ring islow,but when the rolling element guides and the inner ring guides,the air pressure value of the outer ring contact area increases.(3)Under different guide methods of the cage,vortices will appear as the speed increases,and the center of the main vortex will not change at the entrance end surface as the speed increases,the intensity of the vortex increases,and tiny vortices will easily form new Gas barrier.In the cage rolling element guide mode,vortexes are formed between the cage and the outer ring at the entrance and exit faces,and the vortex at G is closer to the ball surface than at A.When the outer ring guides,a vortex is formed between the cage and the inner ring at the entrance and exit end faces.The vortex at the outlet end has a certain offset to the outlet.When the inner ring is guided,the vortexes at the entrance and exit surfaces at the A position and the G position are away from the ball surface.(4)Under different guide modes of the cage,the temperature of each cross section of the bearing in the circumferential direction is the highest when the rolling body guides the cage as a whole,followed by the inner ring guide cage and the outer ring guide cage.The circumferential temperature of the outer ring guide is the largest,and the temperature change in the bearing cavity is the smallest when the rolling body is guided,and the distribution is most uniform.The overall temperature in the bearing cavity rises with increasing speed.At lower speeds,the temperature rise of the rolling element guide and the inner ring guide is lower.As the speed increases,the outer ring guide is more suitable.