动载荷下径向轴承的非牛顿介质润滑  

Non-Newtonian Medium Lubrication in Journal Bearings under the Effect of Dynamic Load

作　　者：陈皓生[1] 陈大融[1] 汪家道[1] 李永健[1] 

机构地区：[1]清华大学摩擦学国家重点实验室,北京100084

出　　处：《润滑与密封》2005年第5期29-31,37,共4页Lubrication Engineering

基　　金：高等学校博士学科点专项科研基金资助课题(2030003026).

摘　　要：为分析动载荷条件下非牛顿介质的流变特性对径向轴承润滑效果的影响,推导了相应的雷诺方程。在方程中用差分粘度和第一正应力差函数表征非牛顿介质的流变特性,用挤压项表示动载荷作用。轴承润滑的数值计算结果表明,差分粘度的变化是影响承载力的主要因素,它取决于非牛顿介质的动态参数和剪切频率范围,使得非牛顿介质润滑的承载力并不总是高于或低于牛顿介质。在动载荷条件下,第一正应力差效应明显增强了油膜压力和承载力,并对轴心轨迹产生影响。To analyze the effects of non-Newtonian lubricants to the journal bearing lubrication under the condition of dynamic load, a modified Reynolds equation was derived. In the equation, differential viscosity and the first normal stress difference function were defined to specify the theological properties of non-Newtonian medium, squeeze item was used to specify the effect of dynamic load. Numerical results of the lubrication show that the differential viscosity is the principal factor in the lubrication,it is determined by the material parameters of the lubricant and is affected by the shearing frequency.The load capacity of non-Newtonian lubricants is not always higher or always lower than that of Newtonian lubricants. The effect of the first normal stress difference increases the load capacity obviously under the condition of the dynamic load, and it also affects the locus of shaft center.

关 键 词：非牛顿介质 润滑 动载荷 径向轴承 

分 类 号：TH117[机械工程—机械设计及理论] O357[理学—流体力学]