Assembly accuracy prediction and optimization of aero-engine rotor under the separation condition of assembly and measurement

The measurement and assembly of the aero-engine rotor are separated from each other, which makes it difficult to keep the assembly datum consistent with the measurement datum; the existence of the datum error will cause the characteristic matrix to fail to truly reflect the geometric state of the rotor itself and cause the assembly model to be inaccurate, then ultimately affect the assembly accuracy prediction. Combined with the fact that the geometric characteristics of parts/components are not related to the measurement datum, the datum error elimination method has been proposed which makes the rotor characteristic matrix and assembly model more accurate, thereby improving the prediction effect of assembly accuracy. At the same time, the proposed direct optimization strategy is more efficient than the traditional genetic algorithm. The assembly experiment of the aero-engine rotor shows that the model and method proposed in this paper can better reflect the geometric characteristics of the rotor itself and are beneficial to reduce the coaxiality of the front and rear fulcrum. The related research also has reference significance for other large-scale and high-precision mechanical product assemblies.