Characteristics of supersonic flow in new type externally pressurized spherical air bearings  

作　　者：WANG Fu-sheng BAO Gang 王福生;包钢(School of Mechanical and Electrical Engineering,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]School of Mechanical and Electrical Engineering,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Journal of Central South University》2012年第1期128-134,共7页中南大学学报（英文版）

基　　金：Project(2002AA742049) supported by the National High Technology Research and Development Program of China

摘　　要：In order to predict accurately the characteristics of supersonic flow in new type externally pressurized spherical air bearings under large bearing clearance and high air supply pressure, which could decrease their load carrying capacity and stability, a CFD-based analysis was introduced to solve the three-dimensional turbulent complete compressible air flow governing equations. The realizable κ-ε model was used as a turbulent closure illustrate that the interaction exists between shock waves The supersonic flow field near air inlets was analyzed. The flow structures and boundary layer, and the flow separation is formed at the lower comer and the lower wall around the point of a maximum velocity. The numerical results show that the conversion from supersonic flow to subsonic flow in spherical air bearing occurs through a shock region （pseudo-shock）, and the viscous boundary layer results in the flow separation and reverse flow near the shock. The calculation results basically agree with the corresponding experimental data.In order to predict accurately the characteristics of supersonic flow in new type externally pressurized spherical air bearings under large bearing clearance and high air supply pressure,which could decrease their load carrying capacity and stability,a CFD-based analysis was introduced to solve the three-dimensional turbulent complete compressible air flow governing equations.The realizable κ-ε model was used as a turbulent closure.The supersonic flow field near air inlets was analyzed.The flow structures illustrate that the interaction exists between shock waves and boundary layer,and the flow separation is formed at the lower corner and the lower wall around the point of a maximum velocity.The numerical results show that the conversion from supersonic flow to subsonic flow in spherical air bearing occurs through a shock region(pseudo-shock),and the viscous boundary layer results in the flow separation and reverse flow near the shock.The calculation results basically agree with the corresponding experimental data.

关 键 词：supersonic flow spherical air bearings Mach number shock wave 

分 类 号：TH133.35[机械工程—机械制造及自动化]