污染物离心附着现象对水润滑动静压滑动轴承的热弹流影响

Effect of Centrifugal Adhesion of Pollutant on Thermal Elastohydrodynamic of Water-lubricated Hybrid Journal Bearing

建立了污染物离心附着的弹流润滑几何模型,采用考虑了热效应的Reynolds方程,针对水润滑动静压滑动轴承因为润滑剂污染的问题进行热弹流理论分析。研究了污染物离心附着现象对轴瓦表面纹理的影响以及接触区润滑膜的压力膜厚变化,分析了由于污染物离心附着堵塞进水孔对接触区润滑膜压力膜厚的影响,探究了污染物附着层对接触区温度场的影响。结果显示:污染物的离心附着现象有效改善了轴瓦表面的粗糙形貌,并缓解了接触区的膜厚波动现象;污染物对进水孔的堵塞程度越大,供水压力越小,接触区的最小膜厚越小,最大压力越大,不利于轴承润滑;污染物附着层对水润滑动静压滑动轴承接触区的温度场有影响,当污染物与轴瓦材料的物性参数相差越大温度场变化越大,反之则变化不大。

The elastohydrodynamic lubrication geometric model of centrifugal pollutants adhesion is established. The thermal elastohydrodynamic numerical simulation of water-lubricated hybrid journal bearings considering its lubricant pollution problem is carried out by using the Reynolds equation with thermal effect. The effect of centrifugal attachment on the surface texture of the bearing pad and the film thickness,pressure change of the lubricating film in the contact zone are studied. The influence of the film thickness and pressure of the contact zone are analyzed as the contaminants are centrifugally attached to plug the water inlet. The influence of the adhering layer on the temperature field of the contact zone is obtained. The results show that the centrifugal attachment of pollutants effectively improves the roughness of the surface of the bearing pad and alleviates the film thickness fluctuation in the contact area. The greater the degree of clogging of the pollutant to the water inlet,the smaller the water supply pressure,the smaller the minimum film thickness,the greater the maximum pressure,which is not conducive to bearing lubrication. The contaminant adhering layer has an effect on the temperature field of the contact zone of the water-lubricated hybrid journal bearing. When the difference of the physical parameters of the pollutant and the bearing material vary largely,the temperature field changes greatly.