Research on flow characteristics of aerostatic circular thrust bearing

Abstract

In order to improve the pressure distribution, the aerostatic circular thrust bearing with single supply hole was studied. In the computational fluid dynamics (CFD) simulation, the laminar model, the turbulent model, the mixture model of laminar and turbulent were used simultaneously. The micro-characteristics of the gas flows were analysed based on the simulation results. One test rig was built for measuring the pressure distribution with the single test hole, and the calculated and experimental results were compared. The results showed that when the gas film clearance is small and the gas flow is subsonic completely, the whole gas flow is laminar flow, which should be calculated based on the laminar model and when the gas film thickness is large and there is supersonic flow in some region, which should be calculated according to the mixture model; at the same time, there is no surface of discontinuity for Mach number and pressure distribution, and no shock, and the pressure is recovered due to the boundary layer separation, the change of the flow state and the change of viscosity. The method for testing the pressure distributions with a single test hole is effective.

Keywords

• flow simulation
• computational fluid dynamics
• viscosity
• machine bearings
• laminar flow
• Mach number
• supersonic flow
• boundary layer turbulence
• subsonic flow
• flow separation
• pressure distribution
• aerostatic circular thrust bearing
• single supply hole
• CFD simulation
• laminar model
• turbulent model
• mixture model
• microcharacteristics
• single test hole
• gas film clearance
• laminar flow
• gas film thickness
• supersonic flow
• flow state
• flow characteristics
• subsonic gas flow
• Mach number
• boundary layer separation
• viscosity