考虑粗糙表面接触配合的航空发动机多级转子装配误差传递建模

Traditional assembly modeling methods for rotor system ignore the influence of the rough surface micro-morphology of rotors, which may lead to inaccurate assembly error propagation modeling and optimization. Hence, an error propagation analysis method of aero-engine multistage rotors assembly is proposed, which comprehensively considers location errors, orientation errors, and rough surface morphology. First, the conjugate gradient method is used to simulate the practical rough surface micro-morphology of the rotor end face. Then, a contact solution algorithm is proposed under the assumption of rigid contact to calculate the equation of the mating surface and the assembly tilt angle after the mating of two rough surfaces. Second, the traditional homogeneous transformation matrix model for assembly error is improved, and a coaxiality error propagation model considering the rough surface morphology of multistage rotors assembly is established. Finally, the front shaft and the first stage disc of the aero-engine are selected as the objects to verify the effectiveness of the precision prediction model, the accuracy of coaxiality prediction using the new model improved 11.55% compared to the traditional model. The research results indicate that the proposed method can improve the precision prediction accuracy of aero-engine multistage rotors assembly, and provide a theoretical basis for the precision assembly of aero-engine rotor system.