Effect of oil film clearance on dynamic characteristics of <?A3B2 pi6?>variable speed rotor with non-concentric SFD

To study the influence of different oil film clearances on the dynamic characteristicsof a non-concentric squeeze film damper (NCSFD) variable speed rotor system, the variable speed rotor system of an aero-engine was taken as the research object, the consistent design principle of rotor dynamic characteristics was put forward, and a simulated rotor was designed. Analysis and experimental study on the dynamic characteristics of the rotor under different oil film clearances were carried out. The results show that the dynamic characteristics of the simulated rotor and the real rotor are in good agreement. Besides, it has been found that a 0.1 mm oil film clearance is more reasonable. In addition, based on the optimized oil film clearance, research on the wide-speed domain of the rotor system was carried out. In the range of 0.51<italic>n</italic> to 1.00<italic>n</italic>, the vibration displacement change does not exceed 4 μm, the vibration acceleration change does not exceed 0.04<italic>g</italic>, and the rotor runs stably within a wide working speed range. The study provides a reference for the engineering design and vibration reduction design of variable speed rotors in aircraft engines.