The dry friction damping model and vibration characteristics of a cylindrical shell structure with damping-ring

To effectively solve the design problem of the damping ring used in the rotating thin cylindrical shell structure of aeroengine, a dynamic analysis model of the combined structure is established, based on its natural modal analysis. The analytical expression of the friction force and the critical slipping angle is derived with reference to the basic theory of mechanics of materials, and also the predicting method of damping work and damping ratio is demonstrated based on the macro sliding model. For the given structure model, the dry friction damping characteristics of the damping ring are studied. The results show that there exist a critical speed and if exceeding it, the damping ring cannot work functionally. Under an identical nodal diameter and vibration stress, the damping ratio increases first and then decreases with the increasing speed with the increase of rotating speed. When the speed is constant, the lower the nodal diameter, the higher the damping ratio it provided. For a given nodal diameter and speed, as the allowable vibration stress increases, the damping ratio rises first and then decreases. In addition, the damping ratio has a linear relationship with the cross-section width of the damping ring.