Circular cylindrical shell flutter analysis based on the unsteady lifting surface theory and experimental verification

Abstract

This paper deals with flutter analysis of a circular cylindrical shell based on the non-planar unsteady lifting surface theory. In this study, experiments are conducted with a cantilevered circular cylindrical shell subjected to inner fluid flow, and vibration characteristics are examined. The unsteady fluid force acting on the shell surface is calculated by using Doublet-point method, which is based on the unsteady lifting surface theory. The equation of motion of the shell coupled with the fluid flow is derived by employing the finite element method. The stability of the system is clarified by using the root locus based on the complex eigenvalue obtained from the flutter determinant. Flutter characteristic is clarified by comparing the analysis results with experimental results. Moreover, the local work by the fluid force on the shell surface, and instability mechanism are clarified.