计入孔隙结构影响的复层含油轴承润滑特性分析

Effects of Pore Structure on Hydrodynamic Lubrication of Multi-Layer Oil Bearings

基于Darcy定律和Kozeny-Carman孔隙方程,建立多孔质复层含油轴承的流体润滑模型,利用有限差分法数值模拟,分析复层结构和孔隙参数对含油轴承润滑性能的影响.得出结论如下:复层含油轴承润滑性能随轴承高度增大而变差,随孔隙率减小而变好,当总孔隙率一定时,较低的表层孔隙率有利于提高复层含油轴承润滑性能.因此设计复层含油轴承时,在保证一定孔隙含油量的前提下,应尽可能减小表层孔隙率.研究工作为复层含油轴承摩擦学性能分析与结构设计提供一定的理论基础.

The hydrodynamic lubrication model for multi-layer oil bearings was established based on the Darcy＇s law.The pores＇ effects depicted with the Kozeny-Carman equation were considered in the analysis.The effects of the bearing structure and the pore structure on the lubrication properties were simulated and discussed with the finite difference method.Results show that the lubrication properties get worse with the increase of the layer heights and the porosity;a lower-permeability surface will be more beneficial to improve the lubrication performance when the total porosity is fixed.Therefore,in the design of doublelayer oil bearings,the surface porosity should be reduced as far as possible as long as the oil content in pores is guaranteed.This work is referential to the analysis of the tribological properties and the structural design of multi-layer oil bearings.