A magnetorheological fluid damper for robust vibration control of flexible rotor-bearing systems: A comparison between sliding mode and fuzzy approaches

Squeeze Film Dampers (SFD) are commonly used for passive vibration control of rotor-bearing systems. The Magnetorheological (MR) and Electrorheological (ER) fluids in SFDs give a varying damping characteristic to the bearing that can provide active control schemes for the rotor-bearing system. A common way to model an MR bearing is implementing the Bingham plastic model. Adding this model to the finite element (F.E.) model of the rotor enables analyzing the rotor bearing behavior. In this work, considering uncertainties, three types of controllers are designed for a rotorbearing system and the efficiency of using these controllers in attenuating the vibration amplitude of the system is studied. As a result, employing these controllers reveals a remarkable improvement in reducing the vibration amplitude of the shaft midpoint near the critical velocity.