Abstract: It is posed that angular air-hammer self-excited vibration and half frequency wobble self-excited vibration are two reasons for resulting angular wobble self-excited vibration for gas film face seals. In the stability analysis of this vibration, the influence of different face configurations, stiffness of the springs supporting the floated ring and damping of the secondary seal are presented. On the basis of small perturbation linearized distributed parameter method, the perturbed Reynolds equations of gas film and perturbed motion equations are simultaneously solved and the limits of stability are obtained by a numerical iteration. The adaptable finite element method is used for calculating the dynamic coefficients of gas film for three degrees of freedom perturbed motions.

Key words: Angular wobble self-excited vibration, Finite element method, Gas film face seal