耦合轴颈轴向运动的粗糙表面径向滑动轴承热流体动力润滑分析

Thermohydrodynamic Lubrication Analysis of Journal Bearing with Rough Surface Coupled the Axial Motion of Journal

在实际轴-轴承系统中,受多种因素作用的影响,轴颈在轴承中不可避免地存在沿轴线方向的运动和倾斜,影响径向滑动轴承的润滑性能。计及轴颈的轴向运动,对粗糙表面倾斜轴颈径向滑动轴承的热流体动力润滑性能进行研究,主要分析讨论热效应、表面粗糙度、偏心率和转速等对计及轴颈轴向运动的倾斜轴颈径向滑动轴承润滑性能的影响情况。其中,采用基于平均流量润滑模型建立的广义Reynolds方程进行润滑分析,采用能量方程和固体热传导方程计算润滑油和轴承温度,采用润滑油黏温方程确定润滑油黏度。结果表明,轴颈轴向运动对轴承润滑性能的影响与轴颈倾角、热效应、表面粗糙度、偏心率和转速有关;随着轴颈轴向速度的增加,热效应对轴承润滑性能的影响减小,表面粗糙度对轴承主要润滑性能的影响略有增大;轴承轴颈倾角和偏心率越大、转速越低,轴颈轴向运动对径向滑动轴承润滑性能的影响越明显。

In the practical shaft-bearing system,due to the influence of many factors,the journal inevitably moves and tilts along the axis in the bearing,which affects the lubrication performance of journal bearing.The thermal hydrodynamic lubrication performance of misaligned journal bearing with rough surface was studied by considering the axial motion of journal.The influences of thermal effect,surface roughness,eccentricity and rotational speed on the lubrication performance of misaligned journal bearing with axial motion were analyzed and discussed.In the study,the generalized Reynolds equation based on the average flow lubrication model was used for the lubrication analysis,the energy equation and solid heat conduction equation were used to calculate the temperature of lubricating oil and bearing,and the viscosity temperature equation was used to determine the viscosity of lubricating oil.The results show that the influence of journal axial motion on the lubrication performance of bearings is related to the journal inclination angle,thermal effect,surface roughness,eccentricity and speed.With the increase of journal axial velocity,the influence of thermal effect on the lubrication performance of bearings decreases,while the influence of surface roughness on the main lubrication performance of bearings increases slightly.The greater the journal inclination and eccentricity,and the lower the speed,the more obvious the influence of journal axial motion on the lubrication performance of journal bearing.