The Nonlinear Research On Sma In Active Control To Rotor System

Shape Memory Alloy (SMA) is a new type of metal material. It has characteristics of shape memory, variable stiffness and super-elasticity. Because of variable stiffness characteristics, the variable stiffness SMA bearing used in rotor system can be designed, and then the stiffness of system can be varied by active control technology when the rotate speed of system is near the critical rotate speed to reduce the maximum vibration amplitude of rotor system. Moreover, we can realize the controllable nonlinear stiffness with SFD because of the soft nonlinearity of SMA in the super-elasticity state, then make the vibration amplitude of system always be in the small solution state when the rotate speed of system rise or fall to reduce the vibration amplitude of rotor system.The phase transformation of SMA cause by the electric heating can control the rotor system too. In the paper, active control to rotor vibration with SMA is studied:Resolving the coupling problem of thermal conduction and thermal elasticity with nonlinear method of perturbation to get more precise answers of U and Ψ. The influences of α,β,λ,G on results are discussed and we get four useful conclusions. So we can control the vibration of the rotor system with the phase transformationUse the controller made of to control the vibration of rotor system working in high temperature. The simulation results show that the controller made of reduce the vibration of rotor system effectively. This paper is supported by national nature science foundation (59975065) and doctor foundation (2000005624).