Performance analysis of air foil thrust bearings withdifferent top foil taper heights
-
摘要: 针对波箔型气体止推箔片轴承,建立了箔片结构二维薄板模型,并通过有限差分法和有限元法耦合求解可压缩气体Reynolds方程和气膜厚度方程,获得了给定轴承载荷条件下轴承气膜压力分布、气膜厚度分布、平箔片变形量和功率损耗等轴承特性.通过对比楔形高度分别为25,70,100,200,300μm时的轴承特性仿真结果研究了楔形高度对轴承性能的影响.结果表明:降低楔形高度使轴承气膜压力分布更均匀,并降低了平箔片的局部集中载荷.但楔形高度存在一个最佳值,使得达到相同轴承载荷所需的最小气膜厚度最大,并且轴承具有最小功率损耗,提高了轴承的工作效率.该结果为气体止推箔片轴承的结构设计提供的理论参考.Abstract: The foil structural 2-D thin plate model of bump type air foil thrust bearing was created, finite difference method (FDM) and finite element method (FEM) were coupled together to solve the compressible air Reynolds equation and film thickness equation. The bearing performance such as pressure distribution, film thickness, top foil deformation and power loss were obtained in specific bearing load condition, and the effects of taper height on bearing performance were studied by comparing simulation results with 25, 70, 100, 200, 300μm taper heights. The results show that reducing taper height can make pressure distribution more uniform and reduce the concentrated force on top foil. However, with an optimum value, the bearing can maximize the minimum film thickness for the required same load capacity. Also the bearing can realize the lowest power loss, and the bearing efficiency is improved. These results can be treated as a guideline of air foil thrust bearing design.
-
Key words:
- air foil thrust bearing /
- taper height /
- top foil deformation /
- minimum film thickness /
- power loss
-
[1] Agrawal G L.Foil air or gas bearing technology:an overview[R].ASME Paper GT1997-347,1997. [2] Feng K,Kaneko S.Analytical model of bump-type foil bearings using a link-spring structure and a finite-element shell model[J].Journal of Tribology,2010,132(2):021706.1-021706.11. [3] Kim D J,Andron C,Chang S S,et al.Mesoscale foil gas bearings for palm-sized turbomachinery:design,manufacturing,and modeling[J].Journal of Engineering for Gas Turbine and Power,2009,131(4):042502.1-042502.10. [4] Blok H,Rossum J J.The foil bearinga new departure in hydrodynamic lubrication[J].Lubrication Engineering,1953,9(6):316-320. [5] Heshmat H,Walowit J A,Pinkus O.Analysis of gas-lubricated foil journal bearings[J].Journal of Lubrication Technology,1983,105(4):647-655. [6] Peng Z C,Khonsari M M.Hydrodynamic analysis of compliant foil bearings with compressible air flow[J].Transactions of the ASME,2004,126(3):542-546. [7] Peng Z C,Khonsari M M.On the limiting load-carrying capacity of foil bearings[J].Journal of Tribology,2004,126(4):817-818. [8] Peng Z C,Khonsari M M.A thermohydrodynamic analysis of foil journal bearings[J].Journal of Tribology,2006,128(3):534-541. [9] Roger K C P,Heshmat H.Compliant foil bearing structural stiffness analysis:Part Ⅰ theoretical model including strip and variable bump foil[J].Journal of Tribology,1992,114(2):394-400. [10] Ruscitto D,McCormick J,Gray S.Hydrodynamic air lubricated compliant surface bearing for an automotive gas turbine engine Ⅰ:journal bearing performance[R].NASA CR-135368,1978. [11] Andrés L S,Kim T H.Improvements to the analysis of gas foil bearings integration of top foil 1D and 2D structural models[R].ASME Paper GT2007-27249,2007. [12] Heshmat H,Walowit J A,Pinkus O.Analysis of gas-lubricated complaint thrust bearings[J].Journal of Lubrication Technology,1983,105(4):105:638-646. [13] Roger C P.Dynamic structural properties of compliant foil thrust bearings-comparison between experimental and theoretical results[J].Journal of Tribology,1994,116(1):70-75. [14] Iordanoff I.Analysis of an aerodynamic compliant foil thrust bearing:method for a rapid design[J].Journal of Tribology,1999,121(4):816-822. [15] Heshmat C A,Xu D S,Heshmat H.Analysis of gas lubricated foil thrust bearings using coupled finite element and finite difference methods[J].Journal of Tribology,1999,122(1):199-204. [16] Park D J,Kim C H,Jang G H,et al.Theoretical consideration of static and dynamic characteristics of air foil thrust bearing with tilt and slip flow[J].Tribology International,2008,41(4):282-295. [17] Lee D,Kim D J.Design and performance prediction of hybrid air foil thrust bearings[J].Journal of Engineering for Gas Turbine and Power,2010,133(4):042501.1-042501.13. [18] Gad A,Asme A,Kaneko S.A new structural stiffness model for bump-type foil bearings:application to generation Ⅱ gas lubricated foil thrust bearing[J].Journal of Tribology,2014,136(4):041701.1-041701.13. [19] 戚社苗,耿海鹏,郭海刚,等.弹性箔片动压气体推力轴承承载性能研究[J].润滑与密封,2006,31(5):1-4. QI Shemiao,GENG Haipeng,GUO Haigang,et al.Theoretical research on the load performance of aerodynamic compliant foil thrust bearings[J].Lubrication Engineering,2006,31(5):1-4.(in Chinese) [20] 周权,赵祥雄,陈汝刚,等.基于有限差分法的动压气体止推轴承静态特性分析[J].润滑与密封,2009,34(8):6-9. ZHOU Quan,ZHAO Xiangxiong,CHEN Rugang,et al.Static characteristic analysis of aerodynamic gas thrust bearing based on finite difference method[J].Lubrication Engineering,2009,34(8):6-9.(in Chinese) [21] Ventsel E,Krauthammer T.Thin plates and shells:theory,analysis,and applications[J].Applied Mechanics Reviews,2002,55(4):1813-1831.
点击查看大图
计量
- 文章访问数: 757
- HTML浏览量: 0
- PDF量: 498
- 被引次数: 0