Atenuação de vibrações laterais em um rotor flexível utilizando ligas de memória de forma

Abstract

This research presents the numerical modeling and investigates the dynamic behavior of a flexible horizontal rotary machine with wires shape memory alloys (SMA) applied in different positions of the rotor (bearing and discs), aiming at attenuating the lateral vibrations. Compared to other classes of smart materials, the SMA provides higher work capacity per unit of volume, so it is considered as an efficient actuator to reduce vibration amplitudes. The rotary machine is modeled using the Finite Element Method, and the thermomechanical behavior of the SMA is represented mathematically by the modified Brinson’s constitutive model, contemplating only the pseudoelastic effect. In this case, the first analysis consists of applying the SMA wires in the flexible bearing along with the horizontal and vertical directions. In the second application, the SMA wires are attached to the disc and the shaft. The numerical results with the wires applied to the bearing were satisfactory, as there was a reducing the amplitude of the lateral vibrations in the rotating axis at acceptable levels, as shown in the steady-state and run-up responses of the rotor. For SMA wires applied to the discs, there was no significant reduction, but the application methodology is promising. The numerical results of this work demonstrate the effectiveness of the semi-active control approach in the memory shape alloys applied to rotate machines.