FREE-VIBRATION OF A CIRCULAR CYLINDRICAL-SHELL FILLED WITH BOUNDED COMPRESSIBLE FLUID

This paper presents an analytical method for evaluating the linear fre e vibration of a circular cylindrical shell filled with bounded compre ssible fluid. The analytical method was developed by means of the fini te Fourier series expansion method. The motion of compressible fluid c oupled with the shell was determined by means of the linearized veloci ty potential flow theory. To clarify the validity of the analytical me thod, the coupled natural frequencies of a water-filled circular cylin drical shell with a clamped-clamped boundary condition were obtained b y the analytical method and finite element analysis. Excellent agreeme nt on the natural frequencies of the liquid-coupled shell structure wa s found. The results show that the natural frequencies decrease with a n increase in fluid compressibility. However, the compressibility effe ct on the lower circumferential mode frequencies was found to be relat ively significant. Additionally, it was found that the rigid bounding of fluid at the ends of the shell decreases the natural frequencies fo r the lower circumferential modes when compared with the sloshing flui d case. (C) 1998 Academic Press.