内外环对高速球轴承中球体拖曳阻力系数的影响

In high speed oil-lubricated ball bearings, rolling elements are resisted by lubricating fluid, changing the bearing's dynamic and thermal behaviour. In order to investigate the effects of inner and outer rings on the ball's drag coefficient, a numerical simulation model and an experimental device are developed with one single sphere confined by two flat walls. The changing rule of drag coefficient is summarized and compared with that of one sphere in open space. Results show that the numerical model is reliable with an error of less than 10% compared with the experiment. For the same Reynolds number, the pressure difference between the upstream and downstream of the sphere is enlarged obviously with the restriction of two walls, rising the drag coefficient to a high level. It's illustrated that drag coefficient on sphere in restricted space is about two times to that of sphere in open space in the range of 10³<Re<10⁵.