理想气体条件下平行圆盘止推气体轴承承载力特性研究  

Load characteristics of parallel circular aerostatic thrust bearing in adiabatic perfect gas

作　　者：郭良斌[1] 彭宝林[1] 

机构地区：[1]武汉科技大学机械自动化学院,湖北武汉430081

出　　处：《武汉科技大学学报》2011年第1期62-68,共7页Journal of Wuhan University of Science and Technology

基　　金：国家自然科学基金资助项目(50335010);湖北省自然科学基金资助项目(2006ABA289);武汉科技大学科学研究发展基金资助项目(2005XZ2)

摘　　要：在高供气压力和大间隙下,平行圆盘止推气体轴承间隙中呈现出超音速主流区与边界层的复杂作用而导致高度复杂的流场。为探讨超音速主流区的特性,采用绝热理想气体和简化轴承模型分析环境背压不变时气膜间隙中流动状态与供气总压的依赖关系,推导出以供气总压和马赫数为主要变量的不同流态下轴承承载力的计算公式。结果表明,随着供气总压的变化,间隙内可能出现4种不同的流动状态,具体由供气总压与3个特征滞止压强的比值来决定;3个特征滞止压强与出口背压的比值仅取决于圆盘的内外半径比。当供气总压在环境背压和第2特征滞止压强之间时,随着供气总压的增大,轴承承载力从0降至最低负值;当供气总压大于第2特征滞止压强时,轴承承载力随着供气总压的提高而线性增大。Under high air supply pressure and large bearing clearance an extremely complex fluid flow in the clearance of parallel circular aerostatic thrust bearings is formed due to radially thickening boundary layers interacting with the supersonic main flow.In order to study the characteristics of supersonic main flow,the interdependence between flowage and supply stagnation pressure is analyzed by adopting adiabatic perfect gas model.Formula of bearing load under different flowages is deduced with supply stagnation pressure and Mach number as the main variables.The calculation results of example indicate that four different kind of flowage in air gap may be formed under different supply stagnation pressures,determined by the ratio of supply stagnation pressure to the three character stagnation pressure.The ratio of three character stagnation pressure to backing pressure of exit is determined by radius ratio of the circular alone.When supply stagnation pressure is between ambient backing pressure and the second character stagnation pressure,bearing load decreases from zero to minimal negative value with the increase of supply stagnation pressure.When supply stagnation pressure is greater than the second character stagnation pressure,bearing load increases linearly with the increase of supply stagnation pressure.

关 键 词：平行圆盘止推气体轴承 绝热理想气体 特征滞止压强 承载力 

分 类 号：TH133.36[机械工程—机械制造及自动化] TH117.2