Experiment and Simulation Analysis of the Vibration Response of the Rotor-bearing System

The unbalanced mass of the rotor-bearing system may cause abnormal vibration of the rotor-bearing system, which may affect the safe operation of the system in severe cases. In this paper, the rotor-bearing system fault simulation test bench and MADYN 2000 were used to test and simulate the single-disk shafting rotor mass unbalance fault. The research analyzes the influence of speed, unbalanced mass, support stiffness, and phase of unbalanced mass on the vibration response of the rotor-bearing system. The results show that when the speed is higher than the first-order critical speed, after the rotor starts, the amplitude gradually increases with the speed, reaches the peak at the first-order critical speed, and then gradually decreases to a stable value. Due to the anisotropy of the bearing support, the rotor has different amplitudes in each direction, but the change trend is the same, the support stiffness is small, and the stable value is reached faster. When the rotation speed and the unbalanced mass phase are the same, the rotor amplitude and the rotor unbalanced mass have a linear relationship. When the speed and unbalanced mass are the same, the rotor amplitude fluctuates with the change of the loading phase, and the fluctuation period is π. The research results have certain reference significance for the fault diagnosis and dynamic characteristics analysis of the unbalanced response of the rotor-bearing system.