Flutter Analysis and Experiments of a Rectangular Sheet Supported by a Wire

Abstract

This paper deals with a flutter analysis of a rectangular sheet supported by a wire in axial flow. In the flutter analysis, Doublet-point method based on the unsteady lifting surface theory is used to calculate the unsteady fluid force acting on the sheet surface. The equation of motion of the sheet supported the wire with tension is derived by using the finite element method. The flutter velocity and mode of the sheet are examined through the root locus of the flutter determinant of the system with changing the flow velocity. In this study, experiments are conducted and compared with the analytical results. The flutter velocity, its mode, and the local work by the fluid force acting on the sheet surface with changing tension of wire are determined. Moreover, the effects of boundary condition on flutter characteristic are determined. As the tension of the wire becomes higher, the flutter velocity and its frequency increase. Traveling-wave mode flutter occurs to the sheet when the flow velocity becomes higher. In the case of lower tension of the wire, the amplitude of the flutter mode at the upstream end is large. The local work done by the fluid force around the center of the sheet is positive, and that near the downstream end of the sheet is negative. Moreover, local work on the sheet surface and flutter mode for different boundary condition depend on dominant mode contribute to flutter mode.