The Study Of Flow Characteristics Of Intermittent Air Source Of Gas Bearing

Gas bearing is widely used as it has many advantages such as high precision, fastspeed, no pollution radiation resistant. Gas bearings rely on a gap of several micronsthat contains a gas to support the moving parts of a machine.The supply pressureof gasbearings with traditionalstructure is usually small,simultaneously consuming only smallamounts of gas andhaving a low bearing capacity. With the development of gas bearingtechnology and the needs of actual production,heavygas bearings with high supplypressure and highgas consumption need to be developed. In order toanalyze thecharacteristics of circular gas bearings using an experiment with an interaction betweenthe rarefaction wave and supersonic boundary layer, a test-bed isneeded to determinewhich methods will meet therequirements of the experiments.This study adopted anintermittent air source for use withthetest-bed for use in the gasbearingexperimentswitha large flux, because large quantitiesof gas were consumed.The paper mainly research the following contents:1. The pipeline mathematical model of one-dimensional unsteady flow wasestablished and the method of characteristics were used to solve the non-homogeneouspartial differential equations.2. The container of intermittent air source mathematical model was established andthe state of container were solved.3. The ball valve opened gradually and the flow area was different which hasimpact on the pipeline flow. The valve used in this experiment was simplified as avariable orifice. The valve of orifice changes during the process of opening the ballvalve.4. Aprogram was written in the FORTRAN95computer language and was used tocalculate the model.The model is able to calculate the state change of container of intermittent airsource and the deflation time. We could get the time of gas within the pipeline beginning a quasi-steady flow and the change of gas velocity and pressure in thepipeline.