Rub-Impact Dynamics of Shrouded Blades under Bending-Torsion Coupling Vibration

Shroud devices which are typical cyclic symmetric structures widely used to reduce the vibration of turbine blades in aero engines. Asymmetric rub-impact adjacent shrouds or aerodynamic excitation forces can excite bending-torsion coupling shrouded blades, will lead complex contact motions. The aim this paper is study dynamic characteristics using a numerical method. contact-separation transition mechanism under motions studied, corresponding boundary conditions set up, and influence moments on motion blade considered. A three-degree-of-freedom mass-spring model including two mass blocks with same size shape established simulate vibration, equations different derived. An algorithm based fourth-order Runge–Kutta method presented for simulations. Variation laws forced response parameters basis evaluate reduction system when chaotic discussed. Then, law obtained.