Sealing performance is significantly affected by the change of seal face topography produced by thermal and force deformation or machining. A mathematical model of spiral groove liquid film seal considering radial taper and circumferential waviness was established. The dynamic Reynolds equation was solved by partial derivative method and the opening force

stiffness

dynamic stiffness and dynamic damping coefficients of liquid film seal were obtained by means of finite element method

and then the influence of radial taper and circumferential waviness on steady and dynamic characteristics of liquid film seal were analyzed. The results indicated that the opening force of liquid film seal decreased with the increase of taper and increased with the increase of waviness amplitude. Under the same waviness amplitude

the opening force was reduced with the increase of waviness number. Stiffness of liquid film gradually reduced with the increase of taper and the variation trend with waviness amplitude was different with the change of waviness number. The absolute values of dynamic stiffness coefficients of liquid film decreased with the increase of taper and the effects of waviness on axial stiffness coefficient and angular stiffness coefficients were more obvious. Dynamic damping coefficients of liquid film gradually decreased with increasing taper and increased with increasing of waviness amplitude.