Abstract: There is a contradiction between bearing capacity and stability of the aerostatic restrictors. The bearing capacity of commercial restrictors applies only to small-load instrumentation. In order to improve the bearing capacity and stable the flow field, an aerostatic restrictor with microchannels has been designed and produced. The said restrictor combines the orifice and torus throttling methods, so it has a secondary throttling effect. Also, it has two individual parts for an interference fit. Therefore, it is radically innovative in both the design concept and the mechanical structure. To test the bearing capacity performance of the self-designed aerostatic restrictor with microchannels, theoretical approximate calculations of bearing capacity due to compound throttling method are carried out, and theoretical bearing capacity curves under different gas pressure are obtained. The bearing capacity of the said restrictor is measured under different gas pressure through experiments, and compared with the theoretical curves, which are in accordance with the former. Two widely used aerostatic restrictors with similar throttling area are selected as controls and compared with the said restrictor in bearing capacity. Besides, the data and the error sources are analyzed. The experimental results demonstrate that the aerostatic restrictors with microchannels could greatly improve the bearing capacity. Under the same gas pressure, the bearing capacity of the said restrictor is significantly higher than the other two restrictors. Therefore, the aerostatic restrictors with microchannels have promising prospect of engineering application.

Key words: Aerostatic restrictor, Air film stiffness, Air film thickness, Static performance