The vortex formed around the rolling ball and the high pressure region formed around the ball-raceway contact zone are the principle factors that barricades the lubricant entering the bearing cavity, and further cause...The vortex formed around the rolling ball and the high pressure region formed around the ball-raceway contact zone are the principle factors that barricades the lubricant entering the bearing cavity, and further causes improper lubrication. The investigation of the air phase flow inside the bearing cavity is essential for the optimization of the oil-air two-phase lubrication method. With the revolutionary reference frame describing the bearing motion, a highly precise air phase flow model inside the angular contact ball bearing cavity was build up. Comprehensive factors such as bearing revolution, ball rotation, and cage structure were considered to investigate the influences on the air phase flow and heat transfer efficiency. The aerodynamic noise was also analyzed. The result shows that the ball spinning leads to the pressure rise and uneven pressure distribution. The air phase velocity, pressure and cage heat transfer efficiency increase as the revolving speed increases. The operating noise is largely due to the impact of the high speed external flow on the bearing. When the center of the oil-air outlet fixes near the inner ring, the aerodynamic noise is reduced. The position near the inner ring on the bigger axial side is the ideal position to fix the lubricating device for the angular contact ball bearing.展开更多
A dynamics formula was established for the flexible cage of high-speed angular contact ball bearing. A modified Craig-Bampton component mode synthetic method was used to establish the formula with regard to the flexib...A dynamics formula was established for the flexible cage of high-speed angular contact ball bearing. A modified Craig-Bampton component mode synthetic method was used to establish the formula with regard to the flexibility of cage and based on a dynamic analysis of angular contact ball bearing,and a rigid-flexible multi-body dynamic analysis program was developed using ADAMS,which is verified by a computation example of Gupta. The results show that it's not likely to keep the rotation smoothness of cage when the ratio of pocket clearance to guiding clearance and the ratio of radial load to axial load become too large or too small. By comparison,the flexible cage runs more smoothly than the rigid cage.展开更多
在套圈表面设计微织构已成为轴承润滑增效的1种有效方法,本文中基于VOF(Volume of fluid)理论建立了润滑油滴在球轴承内圈织构化表面润湿铺展的三维数值模型,对比分析了油滴在常规内圈滚道和织构化内圈滚道表面的铺展和润湿特性,剖析了...在套圈表面设计微织构已成为轴承润滑增效的1种有效方法,本文中基于VOF(Volume of fluid)理论建立了润滑油滴在球轴承内圈织构化表面润湿铺展的三维数值模型,对比分析了油滴在常规内圈滚道和织构化内圈滚道表面的铺展和润湿特性,剖析了微凹坑织构对润滑油滴铺展的作用机理及影响因素,搭建了液滴动态监测平台与接触角测量平台,将试验结果与数值分析结果进行对比,验证了数值分析的正确性.结果表明:织构使轴承内圈表面润滑油滴接触角减小、铺展长度和铺展面积增大,提高了滚道表面的润湿性;在旋转的内圈滚道表面,织构对润滑油起到存储和滞留作用,使内圈滚道表面润滑油增加、铺展面积增大,形成更加稳定的润滑薄膜,有利于改善轴承内圈润滑状况.轴承转速越高、织构间距越小、润滑油黏度越小以及油滴初速度越大时,润滑油在旋转滚道表面的铺展面积越大;随着织构深度的增大,油滴铺展面积先增大后减小,40μm是织构的最佳深度.该研究对角接触球轴承内圈织构设计以及润滑增效具有重要参考意义.展开更多
基金Project(2011CB706606) supported by the National Basic Research of ChinaProject(51405375) supported by the National Natural Science Foundation of China
文摘The vortex formed around the rolling ball and the high pressure region formed around the ball-raceway contact zone are the principle factors that barricades the lubricant entering the bearing cavity, and further causes improper lubrication. The investigation of the air phase flow inside the bearing cavity is essential for the optimization of the oil-air two-phase lubrication method. With the revolutionary reference frame describing the bearing motion, a highly precise air phase flow model inside the angular contact ball bearing cavity was build up. Comprehensive factors such as bearing revolution, ball rotation, and cage structure were considered to investigate the influences on the air phase flow and heat transfer efficiency. The aerodynamic noise was also analyzed. The result shows that the ball spinning leads to the pressure rise and uneven pressure distribution. The air phase velocity, pressure and cage heat transfer efficiency increase as the revolving speed increases. The operating noise is largely due to the impact of the high speed external flow on the bearing. When the center of the oil-air outlet fixes near the inner ring, the aerodynamic noise is reduced. The position near the inner ring on the bigger axial side is the ideal position to fix the lubricating device for the angular contact ball bearing.
文摘A dynamics formula was established for the flexible cage of high-speed angular contact ball bearing. A modified Craig-Bampton component mode synthetic method was used to establish the formula with regard to the flexibility of cage and based on a dynamic analysis of angular contact ball bearing,and a rigid-flexible multi-body dynamic analysis program was developed using ADAMS,which is verified by a computation example of Gupta. The results show that it's not likely to keep the rotation smoothness of cage when the ratio of pocket clearance to guiding clearance and the ratio of radial load to axial load become too large or too small. By comparison,the flexible cage runs more smoothly than the rigid cage.
文摘在套圈表面设计微织构已成为轴承润滑增效的1种有效方法,本文中基于VOF(Volume of fluid)理论建立了润滑油滴在球轴承内圈织构化表面润湿铺展的三维数值模型,对比分析了油滴在常规内圈滚道和织构化内圈滚道表面的铺展和润湿特性,剖析了微凹坑织构对润滑油滴铺展的作用机理及影响因素,搭建了液滴动态监测平台与接触角测量平台,将试验结果与数值分析结果进行对比,验证了数值分析的正确性.结果表明:织构使轴承内圈表面润滑油滴接触角减小、铺展长度和铺展面积增大,提高了滚道表面的润湿性;在旋转的内圈滚道表面,织构对润滑油起到存储和滞留作用,使内圈滚道表面润滑油增加、铺展面积增大,形成更加稳定的润滑薄膜,有利于改善轴承内圈润滑状况.轴承转速越高、织构间距越小、润滑油黏度越小以及油滴初速度越大时,润滑油在旋转滚道表面的铺展面积越大;随着织构深度的增大,油滴铺展面积先增大后减小,40μm是织构的最佳深度.该研究对角接触球轴承内圈织构设计以及润滑增效具有重要参考意义.
