An Application of the Novel Linear Magnetic Actuator to Controllable Squeeze Film Damper

An enhancement of the dynamic behavior of the rotating shaft work at high operating speed by using Squeeze film dampers (SFDs) has been becoming an important part in changing the dynamic characteristics of machinery. In this paper, a new type Controllable Squeeze Film Damper (CSFD) is proposed, designed and fabricated by changing the clearance of the thin-film fluid. Both of the critical speed and critical amplitude are reduced with the suitable damping coefficient. A novel Linear Magnetic Actuator (LMA) is investigated and used to move the outer damper of the CSFD. The experiment results illustrate basically the concept of electromagnetic effect as well as the interaction force between electromagnet and permanent magnet. Furthermore, the PID and advanced (a self-tuning fuzzy PID) controllers are subsequently applied to controlling exactly the position of a novel LMA. The experimental results reveal that the vibration behavior of rotor dynamic response is affected effectively by changes of the clearance.