The effect of friction to dry gas seal performance can’t be ignored under the condition of high parameter. Based on the structure characteristics of the sealing system and end⁃face, it was established the calculative model of lubricating gas film, used IC⁃EM to divide the grid. Then, conducted numerical simulation to get gas film pressure distribution and velocity distribution by using Fluent software. Finally, it calculated the friction coefficient of lubricating film by the law of Newton internal friction. The result of research shows that the friction coefficient of the lubricating film increases with the increase of the rotational speed, and it decreases with the increase of the medium pressure and the average film thickness in the groove parameters remain unchanged case. When the operating parameters are unchanged, the film friction coefficient increases with the increase of the root diameter, decreases with the increase of the number of grooves and the depth of the groove, and in 75° to 76° spiral angle range is relatively stable.

According to the characteristics of aerostatic dry gas seals and the gas Reynolds equation, Galerkin method was used to derive the variational equations of pressure distribution of the gas film. Based on the gas film boundary conditions, the derivation process using the finite element method of the steadystate Reynolds equations was given. The pressure fitting curves of different thicknesses of the gas films were obtained by using polynomial fitting. In addition, the opening force was carried out. The fitting formula of the opening force and the film thinckness was obtained according to the opening force of the different film thicknesses.The relationship of the film stiffness and the film thickness was obtained by the derivation of the film thickness.The pressure distribution of the stationary seal ring end face was obtained. A parabolic decreasing trend is showed from the orifice to the inner and outer diameters in the radial direction of the stationary ring seal face. Pressure peak occurs at the orifice. With the increase of the gas film thickness, opening force and gas film stiffness decrease.