Utilization of Sedimentation in Magnetorheological Fluids for Online Rotor Balancing

Abstract:
This contribution presents a system for balancing rotating machines during operation. For this purpose, the usually undesirable tendency of magnetorheological fluid to separate due to the difference in density between carbonyl iron particles and the carrier fluid is utilized. Therefore, three chambers on the rotor are filled with magnetorheological fluid. The magnetorheological fluid is stabilized by permanent magnets integrated in the chambers. By selectively influencing the magnetic field of individual chambers with a fixed electromagnet, the separation can now be controlled and thus the mass distribution can be balanced. Following the explanation of the functional principle, the sedimentation behavior of different magnetorheological fluids will be discussed and the functionality of the system is demonstrated using an exemplary balancing process. Finally, an additional application of the system for the experimental investigation of the sedimentation behavior of magnetorheological fluid by measuring the unbalance is presented.