Free vibration analysis of the coupled conical-cylindrical shells based on the dynamic stiffness method

摘要

In this paper, an analytic dynamic stiffness method (DSM) is extended to study the free vibration behaviors of a coupled conical-cylindrical shell. Fliigge shell theory is utilized to describe the motions of each shell component. Power series and wave functions are used to express the displacement functions of conical segment and cylindrical segment. By solving the motion equations, dynamic stiffness matrixes for each shell segment are established, respectively. Then, the global dynamic stiffness matrix for the whole coupled structure is obtained by assembling dynamic stiffness matrixes of each shell segment similarly as FEM did. Free vibration behaviors of the coupled shell are obtained based on the global dynamic stiffness matrix. Through comparing vibration results of present method with ones from open literature and FEM, the accuracy and effectiveness of the DSM are validated. In the numerical analysis, effects of the boundary conditions and semi-vertex angles are discussed.