A vibration damping analysis method of turbine blade shroud dampers based on a given eigen-mode

High cycle fatigue damage caused by resonance and forced vibration can significantly affect the life and reliability of turbine rotor blades in aero-engines. The friction damper has been widely used to reduce the resonant stress of blades, on which the turbine blade shroud dampers are highly used. In order to solve the problems of vibration damping analysis and design of shrouded blades dampers, an analytical method without complex and time-consuming nonlinear vibration response has been proposed based on a given eigenmode in this paper. For the serrated shrouded damper, two typical friction models, namely macro-slip model, and microslip model, have been introduced. Additionally, a complete set of damping analysis method has been introduced by the energy method, based on the vibration dynamics principle and eigenmode analyzed by finite element method. Combined with the analysis of the natural vibration characteristics of the shrouded turbine blade, the law of the damping ratio with the relevant design parameters, such as the vibration stress, the pre-twist angle, the friction coefficient and the nodal diameter, was obtained through a calculation example. The method can also provide an important reference for the parameterized design of dampers.