Three dimensional flutter analysis and wind-tunnel experiments of slender webs in cross flow

Abstract

This paper presents a three dimensional flutter analysis of slender webs under tension in cross flow. In the flutter analysis, Doublet-point method based on the unsteady lifting surface theory is used to calculate unsteady fluid force acting on the web surface. The equation of motion of the web under tension is derived by using the finite element method. Flutter velocity, frequency and mode are predicted through the root locus of the flutter determinant of the system with changing flow velocity. The theoretical results are compared to experimental results to confirm validity. Moreover, the local work done by the fluid force acting on the web surface is calculated, and instability mechanism is discussed. Lastly, unified empirical equation of flutter velocities for several parameters of webs is proposed.