孔隙渗流对环面复层含油轴承润滑性能的影响

含油轴承基体中油液的渗流特性对轴承油膜润滑性能影响显著. 以不同孔隙率分布的环面复层含油轴承为研究对象，利用达西定律建立复层含油轴承基体中流体渗流的控制方程，在极坐标下建立环面复层含油轴承系统渗流润滑模型，研究复层环面副系统中油膜压力分布规律，分析轴承结构参数及孔隙渗流行为对油膜润滑性能的影响. 结果表明:复层含油轴承的流体动压力主要发生在环形摩擦面间，从摩擦界面到轴承底面，流体压力逐渐由外缘向圆心部位传导，流体动压力作用面积逐渐增大，压力峰值逐渐降低；随着倾角增大，摩擦界面间的油膜动压效应增强，油膜润滑性能变好；随着表层渗透率或厚度减小，摩擦界面间的油膜的渗流效应减弱，油膜润滑性能提高；与普通单层含油轴承相比，含致密表层的复层含油轴承能降低整体孔隙率，防止过多轴承间隙油液渗入多孔介质，提高轴承润滑性能. 研究工作为明晰环面复层含油轴承渗流行为及润滑机理提供一定理论依据. 

Effect of Porous Seepage on Lubrication Performance of Circular-Face Bilayer Oil Bearing

The percolation characteristics of oil in the porous bearing have a significant effect on the lubricating performance of the oil film. Taking the bilayer oil bearing with different porosity as the object for research, its percolation characteristics in porous medium were described based on Darcy's law. And the bilayer oil bearing seepage lubrication model was established in polar coordinates. The oil film pressure distribution in the bilayer bearing system was studied. The influence of the structural parameters and the seepage behavior on the lubrication performance were analyzed. The hydrodynamic pressure mainly occurred between the annular friction surfaces. From the friction interface to bearing bottom face, the fluid pressure gradually transmitted from the outer edge to the center, the pressure area increased and the pressure peak decreased gradually. With the increase of obliquity, the hydrodynamic pressure effect between friction interfaces was enhanced, and the lubricating performance was improved. The decrease of the surface thickness or porosity weakened the seepage effect between frictional interfaces. Hence, the lubricating performance was improved. Compared with ordinary single layer oil bearing, bilayer oil bearing reduced the whole porosity, prevented oil infiltrating into the porous medium, and had better lubricating performance. The research provided a theoretical basis for clarifying the lubrication mechanism and seepage behavior of bilayer oil bearing.