Theory Research And Experimental Verification On Gas-impedance Model Of Aerostatic Restrictor System

The research showed that the gas flow rate was the key factor affecting thestability of aerostatic restrictor. In this paper, the author explores the relationshipbetween the gas flow rate and pressure, seeks a way to bring flow, pressure andimpedance together. Main research contents are as follows:Firstly, using FLUENT software, simulation was carried out on the circleaerostatic restrictor to find out the relationship between total impedance orimpedance ratio and its structure parameters and the bearing capacity. So it couldprovide the basis and guide for the establishment of impedance model.Secondly, referring to the relevant contents of fluid in the hydraulic resistance,establishing the impedance model of multi-micro channel restrictor, double U-shapedgroove restrictor and dual circular restrictor. And the effective area of the aerostaticrestrictor was analyzed, the relationship between impedance and bearing capacitywas established.Thirdly, with the finite difference method, three restrictor impedance modelswere validated, the parameters was corrected according to the results, and thecorrection factor was a linear function with the gas pressure. For multi-microchannelrestrictor, the correction factor was2.7742Pa0.5078; For double U-shapedgroove restrictor, the correction factor was4.94Pa0.768; For dual circularrestrictor, the correction factor was4.0Pa0.75. After the correction of restrictors,the maximum error of impedance ratio was respectively4.5%,6.667%,21.5%.Finally, using characteristics test platform of aerostatic restrictor, the capacity wasmeasured with different gas pressure and different gas film thickness of restrictor.The comparison of the measurement results, the impedances and numerical solutionsshowed that the impedance method was similar with the other two methods incalculating bearing capacity, which proved that the credibility of builded model. Atthe same time, three different restrictor models were established using the samemethod, which illustrated the versatility of this method. It could provide a new way for designing aerostatic restrictor in engineering.