热效应对径向浮环轴承最小油膜厚度及稳定性影响研究  

Thermal effect on the minimum film thickness and stability for a journal floating ring bearing

作　　者：杨帅[1] 郭红[1] 张泽斌[1] YANG Shuai;GUO Hong;ZHANG Zebin(School of Mechanical and Power Engineering,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]郑州大学机械与动力工程学院,郑州450001

出　　处：《振动与冲击》2020年第18期215-222,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(51575498)。

摘　　要：以径向浮环动静压轴承为研究对象,采用有限元法和有限差分法联立求解Reynolds方程、能量方程和温黏关系式,得到内外层油膜的压力分布、温度分布和黏度分布,对油膜压力积分得到轴承的刚度系数和阻尼系数。针对轴颈、浮环建立统一的动力学方程,结合能量方程和Routh-Hurwitz准则推导出单质量刚性对称浮环轴承-转子系统的热失稳判据,分析了油膜热效应对内外膜最小油膜厚度与失稳转速的影响。结果表明:内外膜油腔呈现多个的温度峰值,两端面温度高于油腔中央温度;内外膜最小油膜厚度和系统失稳转速随着进油温度的升高而减小;高速工况下,油膜温升是导致浮环轴承发生油膜破裂和失稳现象的重要因素,计算时需计入油膜热效应对轴承性能的影响。The finite element method and the finite difference method were combinedly used to solve the Reynolds equations,energy equations and temperature-viscosity equations for a journal floating ring bearing.The inner and outer fluid film pressure distribution,temperature distribution and viscosity distribution were calculated and the pressure was integrated to calculate the bearing stiffness and damping coefficients.The united dynamic equations were established for the shaft and floating ring,and the thermal instability criteria was derived for a single-mass rigid symmetric rotor system using energy equations and Routh-Hurwitz method.The results show that there are several temperature peaks in the inner and outer film pockets,and both ends temperature are higher than the pocket center temperature.The inner and outer minimum fluid film thickness and threshold speed fall rapidly while the inlet temperature is increasing.The lubricant temperature rise is an important factor causing the floating ring bearing fluid film to rupture and be instable,so the lubricant thermal effect should be considered in the bearing performance analysis.

关 键 词：径向浮环轴承 热效应 最小油膜厚度 失稳转速 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3