A NUMERICAL STUDY OF THE STABLE DYNAMIC BEHAVIOR OF RADIAL FACE SEALSWITH GROOVED FACES

This paper presents a simple numerical method for modeling the dynamic tracking modes of a grooved face seal. The stability is verified usin g a method derived from that developed for smooth face seals. The meth od, enabling the calculation of the kinematic parameters which describ e the steady-state response of the grooved seal, is of interest in des igning this type of seal. A parametric study is presented for the case of a rotor face with eight semicircular grooves. The principal effect of the grooves is to increase the hydrostatic component of the load. In turn, this makes the seal less sensitive to fluctuations of the hyd rodynamic phenomena. Sinusoidal waviness is used to simulate the perio dic distortions induced by the grooves and affects the dynamic behavio r only in the presence of cavitation. This occurs for very small value s of the film thickness and, consequently, for very small leakage flow . In this case, the dynamic response of the seal is then strongly depe ndent upon the hydrodynamic effects.