Research on precision measurement and control methods of rotor center of mass in aircraft engines

As a core thrust-producing component, the rotor of an aircraft engine plays an important role in the stability and reliability of the overall system. Most existing studies focus on the propagation and control of geometric errors during assembly, while center-of-mass shifts caused by nonuniform mass distribution, together with the resulting measurement errors, have received much less attention. In single-stage rotor measurement, nonuniform mass distribution and measurement posture can all introduce considerable errors. When these measurements are used for multi-stage stacking analysis, the errors can accumulate during interstage transmission, which reduces the accuracy of overall center-of-mass prediction and control. Dynamic balancing can partly compensate for these shifts, but it often requires structural modification and may weaken structural integrity and bending stiffness. To address this problem, we model each stage of a multi-stage rotor as an independent mass unit and develop a transmission and regulation model for center-of-mass shifts in multi-stage rotors. The model describes the coupling between centroid shift and geometric errors within each stage, and it characterizes interstage transmission by reconstructing relative assembly phases. Based on this model, we analyze how geometric errors, assembly phase, and measurement deviations at the single-stage level affect the accumulated shift of the multi-stage rotor. We further propose a phase-matching-based method for optimizing assembly angles. Simulation and experimental results show that the overall center-of-mass shift is reduced from 0.236 mm to 0.017 mm, which corresponds to a maximum reduction of 92.8%. These results show that the proposed method effectively limits error amplification during multi-stage stacking.