箔片动压止推气体轴承流固耦合数值模拟  

Numerical Simulation for Fluid-Structure Coupling of Hydrodynamic Foil Thrust Bearing

作　　者：陈汝刚[1] 陈韬[1] 龚超[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2014年第5期72-77,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51076129);中央高校基本科研业务费专项资金资助项目(SYSPZ2011030)

摘　　要：针对鼓泡弹性箔片动压止推气体轴承的结构,在假设内部流体为层流、沿气膜厚度方向压力不变、忽略流体体积力和惯性力的基础上,建立了可压缩性流体Reynolds方程;采用有限差分法,在考虑流场为等温过程的条件下,对Reynolds方程进行了数值求解,得出轴承内部的压力分布。充分考虑鼓泡结构在压力作用下的弯曲变形,采用双向流固耦合模型,分析了顶层箔片的变形与压力场之间的相互作用,结合薄板弯曲模型得出的轴承顶层箔片的变形和气膜间隙分布,分析了轴承数、箔片结构对轴承性能的影响。研究结果表明:支承结构位置不当会直接影响气膜压力的分布,造成承载能力下降;提高轴承数、增大进出口气膜间隙比和轴承内外径之比,可以提高轴承的承载性能;节距比为0.5时承载性能最佳。该结果可为鼓泡弹性箔片动压止推气体轴承的结构设计提供参考。For a hydrodynamic foil thrust bearing with hemispherical convex dots, the compressible fluid Reynolds equation is adopted, where the inner flow is assumed as laminar and, the pressure remains constant along the gas film thickness, and fluid volume force and inertial force are ignored. Finite difference method（FDM）is adopted to numerically solve the Reynolds equation to obtain the pressure distribution under isothermal condition. By sufficiently considering deformation of the hemispherical convex dots under pressure, the model of fluid-structure coupling is used to analyze the interaction between the deformation of the top foil and pressure, and the deformation of top foil and clearance distribution of the gas film are sought out by combining with the thin plate bending model to discuss the effects of bearing number and structure parameter of foil on bearing performance. It indicates that the inappropriate position of supporting structure affects the pressure distribution of gas film directly and weakens the bearing performance; the bearing performance is improved by increasing bearing number, ratio of inlet and outlet gas film clearance and ratio of inner and outer bearing diameter. The optimum performance can be reached at pitch ratio of 0.5.

关 键 词：动压 止推气体轴承 箔片轴承 有限差分法 流固耦合 

分 类 号：TH117.21[机械工程—机械设计及理论]