Wen L., Hongan X.

Cylindrical shells represent a basic structure component widely used in industrial applications. The modal and dynamic characteristics of simply supported cylindrical shells have been well studied and understood in terms of their impacts on sound and vibration. In many real-world problems, however, the boundary conditions cannot be satisfactorily treated as simply supported. Although it is well known that a boundary condition can significantly modify the modal properties and the corresponding dynamic and acoustic responses, the vibrations of shells with the other kinds of boundary conditions including elastic restraints are not frequently considered, probably because of the additional difficulties and/or a lack of general methods. In this paper, the free vibrations of cylindrical shells with general elastic end restraints are investigated through developing a general hybrid analytical-numerical technique. The various homogeneous boundary conditions can also be handled by simply choosing the stiffness constants for the restraining springs to be some special values such as zero or infinity. Since the displacements on a shell is expressed in terms of a set of closed-formed basis functions, this method is advantageous for the vibration analysis of shells at higher frequencies as compared with the traditional grid-based methods such as FEM and FDM.