An analytical study of the effect of different eccentricity and whirling speed on labyrinth seal forces and dynamics parameters

Modeling and calculation are performed for labyrinth seal-rotor system by using numerical methods and commercial CFD (Computational Fluid Dynamics) software. The time spent for computer calculation, pressure distribution in flow field and labyrinth seal forces under five different eccentricities and whirling speeds are researched, respectively. The effects on labyrinth seal leakage and dynamics parameters are also studied by numerical methods. The results show that the method can preferably simulate labyrinth seal leakage and dynamics parameters under different conditions. It gets that pressure and labyrinth seal force increase with eccentricity, and tangential labyrinth seal force increase with eccentricity and whirling speed, while its normal one does in negative direction. Leakage influencing change rate of seal length and gap, sealing pressure difference are 6.62%, 65.21% and 69.97%, respectively, indicating that seals gap and its pressure difference are important impact factors to leakage. Increasing labyrinth seal pressure difference and seal length is not beneficial to seal-rotor system stability, while increasing the seal gap would be good for it.