Minimization of aero-engine assemblies’ dynamic unbalance based on inertial error measurement

Vibration level of aero-engine at high service speed has a direct and significant impact on its dynamic characteristics, while the vibration of aero-engine is mainly induced by dynamic unbalance of rotor systems such as compressors and turbines. For rotor parts, dynamic unbalance is generated by inertial errors during manufacturing and can be amplified immensely by geometrical errors in rotor assemblies, making it crucial to predict and minimize initial dynamic unbalance prior to actual assembling procedures. However, existing unbalance optimization methods lack consideration of couple unbalance, limiting prediction accuracy and optimization efficiency for practical implementations. Dedicating to overcoming the forementioned drawbacks with existing methods, this paper contributed to two major scientific aspects: one is precise measurement of inertial errors for single-stage parts, while another is accurate prediction and adjustment of multistage assemblies’ initial dynamic unbalance based on the measured inertial error. Numerical simulations and experimental verification for proposed methodology were carried out, and the results of assembly experiments with actual aero-engine rotor parts suggest that, by adjusting the second the third stage's assembly phase, dynamic unbalance of 3-stage high-pressure compressor assemblies on correction plane 1 and 2 was reduced by 74.6% and 68.4% compared to worst build strategy correspondingly, and was reduced by 72.6% and 66.1% compared to direct build strategy. Theories proposed in this paper has potency of engineering implementation and can be utilized to achieve precise quality control in measuring and assembling process of aero-engines and gas turbines.