Abstract：In order to improve the performance of an aerostatic dry gas seal, the flow field numerical simulationwas carried out based on the N-S equation, laminar flow model and SIMPLEC algorithm with different throttle diameters and face clearances. The gas film pressure distributes and force changes were analyzed especially. The results show that significant pressure drop formed after the gas flows through orifice, and the drop value increases with clearance increases, decreases with orifice diameter increases. The highestpressure appears at the center of shallow groove, and is gradually declining to around. Bigger pressure gradient appears in the shallow groove near the edge area. The opening force general decreases with clearance, minimum value is close to zero. When the face clearance is in the range of 5-12 μm, the opening force increases rapidly with clearance decreasing, therefore larger gas film stiffness is formed. According to calculations, smaller orifice diameter is helpful to get larger gas film stiffness under the conditionsof less face clearance. Both hydrostatic and hydrodynamic test were carried out, the diameter of the seal tested was 30 mm and the test speed is of 50-300 r/min. The leakage and wear were monitoredand the results show that the sealing achieved stable non-contacting operation.
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