Experimental Research of Bending and Torsional Vibrations of a Double Disc Rotor Due to Rotor-to-Stator Contacts

In this paper,a new rotor to stator contact test rig,which consists of a rotor with two discs mounted on a shaft and a stator,is well built and used to investigate the bending/torsion coupled vibrations of a rotor and an elastic stator due to contacts.The test rig is able to demonstrate partial rub and also the heavily destructive dry friction whip when the rotor rolls on the stator’s inner surface in the real rotating machinery.Both the bending and torsional vibration of rotor and stator vibration are monitored and analysed during the test.Many different kinds of rotor to stator contacts are experimentally simulated with this test rig,such as different rotor imbalance attributing to sudden blade loss,stator support and clearance between rotor and stator,etc.The results show that the torsional vibration of the system reveals very important characteristic of the vibration of rubbing rotor.Rotor to stator contact provokes mainly torsional natural frequency vibration and many phenomena predicted by theoretical studies are found in those experiments.The rotor to stator contact problem can be detected by monitoring the torsional vibration signals.