ESTIMATION OF NONCONSERVATIVE AERODYNAMIC PRESSURE LEADING TO FLUTTER OF SPINNING DISKS

An experimental method for predicting the onset of flutter of a disk spinning in a fluid medium is proposed. The method is based on a description of the aerodynamic loading on the disk as a distributed viscous damping force rotating relative to the disk. This model can arise from two aeroelastic theories described herein. It is shown analytically and experimentally that the few parameters of this model may be extracted from frequency response functions of the spinning disk. Parameters for a steel disk in air (with a near vacuum experiment as reference) are estimated at increasing rotation speeds below the onset of flutter. The flutter speed and mode of the disk are predicted.

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