Analytical–numerical hybrid model for torque transmission in interference fit and torque transmission capacity study

Abstract

The torque transmission capacity serves as a crucial performance indicator for interference fit, directly affecting the safety and reliability of aero-engine. The conventional method for calculating torque transmission capacity of interference fit is based on the thick-walled cylinder theory. Because it relies on idealized conditions of the mating surface, significant discrepancies arise between experimental results and theoretical calculations. To address this issue, this study first proposes an analytical–numerical hybrid (ANH) model for torque transmission in interference fit, which reveals the intrinsic relationships among external torque and other physical quantities on the mating surfaces, such as the distribution of friction coefficients and elastic deformations. Based on this ANH model, a calculation method for the torque transmission capacity of interference fit is then established. By comparing the finite element analysis results of torque transmission in an interference fit between two cylinders, the ANH model was validated in terms of both accuracy and computational efficiency. The distribution characteristics of the friction coefficient on the mating surfaces under different external torque loads were investigated. Finally, torque transmission capability tests were performed on interference fit in aero-engine with varying interference amounts. Compared with the experimental results, the average agreement of the theoretical values obtained using the conventional method and the method proposed in this paper was 40.11% and 101.35%, respectively. The results confirm the effectiveness of the torque transmission capability calculation method based on the ANH model. Compared with the accumulation method, the ANH model shows consistency in the prediction of global slip torque, while its main advantage lies in its ability to characterize the evolution of the friction coefficient distribution and local stick-slip state at the mating interface under partial slip conditions. The proposed method can provide a theoretical basis for torque transmission capacity design and analysis of partial slip states in interference fit.