Stiffness and Deformation Characteristics of the Rabbet Joint Structure in the Central Tie-rod Fastening Rotor

The stiffness characteristics of rabbet joint structures in the central tie-rod fastening rotor have a direct influence on the vibration reliability and stability of the rotor system. In this paper, a stiffness model of the rabbet joint structure is established based on the Hertz theory and the fractal model, considering the cylindrical surface contact. The load distribution and the deformation characteristics of the rabbet joint structure are analyzed. A parametric investigation is conducted to estimate the effects of key parameters on the stiffness of the rabbet joint structure. The results reveal that the end face of the structure bears more than 90% bending moment and more than 60% shearing force. Moreover, a positive correlation between the connection stiffness and the real contact area can be observed, suggesting a potential improvement of vibration reliability of rabbet joint structures by optimizing the contact parameters of the end face.