An experimental study on feedback control of rotating disk flutter

An experimental study is presented in this paper to demonstrate the feedback control of rotating disk flutter. In the experiment, steel disks were rotated between two solid plates and the disk flutter was detected by a laser-Doppler vibrometer. The disk vibration signals were then processed to drive a speaker mounted on one of the supporting plates. The air pressure generated by the speaker was applied to the disks, through a hole in the plate, acting as the control force. The disk mode frequencies, critical speed and flutter speeds were measured for two disks with different sizes, and the results were compared with predicted values. It is shown that the feedback control can effectively suppress the flutter on a large disk (135 mm diameter) rotating up to 11 000 rpm and on a small disk (100 mm diameter) rotating up to 15 000 rpm. Further improvement of the control technique is also discussed.