表面具有凹槽的平行轴承润滑性能的理论与实验研究

Theoretical and Experimental Studies of Lubrication in Parallel Bearing with Grooved Surface

为研究气穴对微尺度下表面纹理中润滑性能的影响,利用自主研发的微型滑块面接触润滑膜厚测量系统对具有4种不同凹槽表面的微型滑块与光滑玻璃面形成的油膜厚度进行测量,并利用高速CCD对试验过程中产生的气穴现象进行观察和拍摄;选用不考虑负压的Reynolds边界条件和考虑气穴的JFO边界条件对二维Reynolds方程分别进行数值求解,并与实验测量值进行比较。结果表明,当有气穴发生时基于JFO边界条件的数值解更接近实验测量值,实验过程中拍摄的气穴图片也印证了这一结论。气穴负压对气穴区宽度影响较大,对入口处的压力峰几乎无影响,而体积弹性模量对入口处的压力峰略有影响,而对气穴区宽度无影响。

To research the influence of cavitation on lubrication performance of surface textured bearing,hydrodynamic lubrication film thickness under different entrainment speeds was measured directly in principle of multi-beam interference by a custom-made test apparatus,in which the lubricated contact consists of 4 different grooved-surface sliders and a transparent rotating glass disc. The phenomenon of cavitation was observed and captured by CCD. By selecting Reynolds boundary condition,which ignores negative pressure,and JFO boundary condition,which considers negative pressure,the two-dimensional Reynolds equation was solved respectively,and these numerical solutions were compared with the experimental results. Relative results suggest that when cavitation occurs the numerical solutions with JFO boundary condition are closer to the experimental results,this concision can be confirmed by cavitation photos taken in the experiment. Cavitation pressure has great influence on the width of cavitation zone,but has little effect on the peak pressure at the entrance. While the bulk modulus slightly influences the entrance pressure peak,and has no effect on the width of cavitation zone.