多叶式波箔气体动压轴承静特性研究  

Numerical Study on Static Characteristics of Multileaf Bump Foil Aerodynamic Bearing

作　　者：吕昕 LV Xin(State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics,Nanjing Jiangsu 210016,China)

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,江苏南京210016

出　　处：《润滑与密封》2022年第4期146-153,共8页Lubrication Engineering

摘　　要：随着旋转机械的不断发展,箔片动压轴承已经发展到了第四代。其中,多叶式波箔气体动压轴承以其大预紧力和耐高温涂层技术的应用而拥有广阔的发展前景。以多箔叠加弹性结构作为切入点,应用悬臂弯曲梁模型和线性弹簧模型来等效箔片结构中的顶层平箔和支承波箔,从而获得不同于前三代箔片动压轴承的气膜厚度方程。基于有限差分法耦合气膜厚度方程和动压Reynolds方程进行迭代求解,得到多叶式波箔气体动压轴承的静态特性结果。改变轴承的转速、偏心率和工况温度,研究其对多叶式波箔动压轴承静态特性的影响。结果表明,偏心率或转速的增大都会使得轴承的最大气膜压力和承载力增大,其中偏心率的影响大于转速的影响;偏位角随偏心率的增大快速减小,即随着偏心率的增大,轴承运转稳定性提升;工况温度的升高会导致轴承最大气膜压力呈线性增大,因此对于高速运转的箔片动压轴承,气动热问题是一个亟需解决的难题。With the continuous development of rotating machinery, foil aerodynamic bearings have developed into the fourth generation.Among them, multileaf bump foil aerodynamic bearing has a bright prospect for development because of its pre-tightening force and the application of high-temperature coating.Taking the multi-foil superposed elastic structure as the starting point, the top flat foil was equivalent to the cantilevered bending beam model and the linear spring model was used to simulate the supporting bump foil, and the film thickness equation different from the previous three generations of bearing’s was obtained.Based on the finite difference method, the gas film thickness equation and dynamic pressure Reynolds equation were coupled for iterative solution to obtain the static characteristics of multileaf bump foil aerodynamic bearing.The influence of rotating speed, eccentricity ratio and operating temperature on the static characteristics of the bearing was studied.The results show that the increase of eccentricity or rotating speed will increase the maximum film pressure and bearing capacity, and the influence of eccentricity is greater than that of rotating speed.The attitude angle decreases rapidly with the increase of eccentricity ratio, indicating the operation stability of bearing is improved with the increase of eccentricity.The increase of temperature will lead to the increase of the maximum film pressure and bearing capacity.Therefore, for the foil hydrodynamic bearing running at high speed, the aerodynamic thermal problem is an urgent problem to be solved.

关 键 词：多叶式波箔轴承 动压轴承 悬臂弯曲梁模型 静态特性 

分 类 号：TH133.37[机械工程—机械制造及自动化]