Three dimensional flutter analysis of a rectangular sheet based on the unsteady lifting surface theory and wind-tunnel experiments

Abstract

This paper presents a three-dimensional flutter analysis of a rectangular sheet in an axial fluid flow. The unsteady fluid force acting on the sheet surface is calculated using Doublet-point method based on the unsteady lifting surface theory. The equation of motion of the sheet coupled with the fluid flow is derived employing the finite element method. The characteristic roots are obtained from the flutter determinant, and the stability of the system is examined with changing flow velocity. The flutter characteristics are clarified comparing the analytical results with wind-tunnel experiments. Lastly, the local work done by the unsteady fluid force on the sheet surface is shown, and the flutter mechanism is discussed.