A theoretical and experimental study has been conducted to investigate the dynamics of cantilevered flexible plates in axial flow. In this paper, a nonlinear equation of motion of plate based on the inextensibility assumption, coupled with an unsteady lumped vortex model for the aerodynamic part is used to analyze the dynamical behaviour of this fluid-structure system theoretically. Experiments have been conducted in a 3 ft × 2 ft wind tunnel, using polypropylene carbonate films, thin brass plates, polyester sheets, and type 304 stainless steel sheets, with maximum dimensions 22.4 cm × 16.8 cm. In the experiments, time traces, PSDs, phase-plane plots, Poincare´ maps, PDFs, and autocorrelations are used to characterize the motions of the system. Periodic, period-doubling and chaotic oscillations have been observed. In the experiments, flutter arises via a subcritical bifurcation accompanied by hysteresis for low aspect ratio plates; the hysteresis disappears for large aspect ratio plates. The hysteresis phenomenon is considered to be due to three-dimensional bending of the plates. Furthermore, for flow velocities in the hysteresis loop, the stable plate subjected to a small external disturbance will flutter with the same amplitude limit cycle oscillation as self-excited oscillation at the same flow velocity. The experimental critical velocities for flutter onset are in good qualitative and quantitative agreement with the theoretically predicted values.

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