An experimental study into dynamic behavior of a magnetorheological fluid squeeze film damper-overhung flexible rotor

摘要

The dynamic behavior of a flexible rotor supported on a magnetorheological(MR)fluid squeeze film damper(SFD)was experimentally studied.The rotor unbalance responses were measured at different rotor imbalances,applied currents,and ER fluids.Some issues,such as modeling,unbalanced magnetic pull force,and sediment,were discussed.It is shown that by application of an external magnetic field on the MR fluid,not only can the MR fluid SFD change the equivalent damping of the rotor system,but also its equivalent stiffness.The break-loose phenomenon observed in the MR fluid SFD rotor system suggests that the MR fluid is most like a non-Newtonian fluid with an initial yield stress.The unbalanced magnetic pull force and the eddy current damping force have a great effect on the dynamic behavior of the rotor system with the lower weight percentage MR fluids,and must be considered in modeling the MR fluid SFD.