Opening characteristics of dry gas seal

The behavior of the start up process of dry gas seal(DGS),which has great significance in engineering was studied based on the steady state analysis.With the hypothesis of critical gas film thickness,a criterion for expressing the opening behavior of DGS,namely the critical opening rotational speed(CORS),was proposed.Changes of the sealing parameters in the opening process,such as gas film thickness,opening force,film stiffness,leakage rate,frictional torque and frictional power consumption were investigated.Influences of operating and structural parameters on the opening behavior of DGS were analyzed.The results indicated that the sealing parameters changed remarkably near the opening critical film thickness in the start up process.CORS was greatly affected by sealing operating pressure,but it could be changed through structural parameter adjustment.By providing a method for analyzing the opening behavior of DGS,this work is helpful for the structural design of seal end faces and the guidance of the opening or closing operation.