Abstract
The vibration model of on a shaft-bladed system is built undergoing both global motion and elastic deformation by finite element method (FEM).The blade’s dynamic equation in rotating reference frame is established.The various effects are analysed such as Coriolis force,centrifugal force,spin softening,acceleration ect,which have influence to a blade vibtation frequencies in varying degrees.The shaft’s dynamic equation in stationary reference frame is deduced by setting gyroscopic matrix and inertia effects.The beam element model in the shaft-bladed system was set and the critical speeds were calculated.Calculation shows that the effects of the prestress and spin softening have great influence on shaft-bladed system vibration frequencies.The blade’s frequencies decreases slightly because the blade stiffness reduced in the system relatively.The work lays a basic foundation for improving the dynamic stability of the rotor system.
Publisher
Trans Tech Publications, Ltd.
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