Experimental and theoretical studies of the dynamic behavior of a spiral-groove dry gas seal at high-speeds

Because of great axial vibration of the rotor system, dry gas seal has a big film thickness disturbance, which may cause contact rubbing of seal faces or excessive leakage. Focusing on this problem, experimental studies on transient-state film thickness and leakage rate of a spiral groove dry gas seal at high-speeds are carried out under different spring pressures and different spiral groove depths. And the experimental results of film thickness disturbance and average leakage rate are predicted by perturbation method and gas lubrication theory. Results show that the theoretical results of variation trends of film thickness disturbance amplitudes coincide well with the experimental data, and it also represents that the perturbation method is an effective forecasting method in dynamic analysis.