The stiffness characteristics of flange joint with a snap were studied by numerical simulation. The hysteresis characteristic of the flange joint with a snap was analyzed using ANSYS. Based on the analysis of the deformation and sliding of the snap contact surface

a Jenkins friction element was used in parallel with a spring element to simulate a section of the flange joint

and the simplified model of the bending stiffness of the whole flange structure was established according to different states of each section during the bending deformation of the flange. The simplified model can be utilized to simulate the stiffness characteristics of the flange joint with a snap accurately. The rotor model was built based on the stiffness simplified model and beam element

and the influence of the flange joint with a snap on the steady-state response of the rotor was analyzed. The results show that the hysteresis characteristic of the flange joint with a snap can affect the peak frequency and reduce the response peak significantly with the increase of snap interference

producing a good vibration suppression effect.