Vibration behaviors of orthogonally stiffened cylindrical shell coupled with internal circular plates in wavenumber-frequency domain

Abstract

In this paper, vibration characteristics of orthogonally stiffened cylindrical shell coupled with multiple internal circular plates are discussed using wavenumber analysis. The theoretical model and formulation for the orthogonally stiffened cylindrical shell coupled with internal circular plates are developed by employing a modified variational method. A unified variational modeling procedure is employed to ensure the continuity conditions between each substructure, including cylindrical shell, circular plate, longitudinal stringer, and circumferential ring. The displacement components of the cylindrical shell are described by Fourier series along the circumferential direction and orthogonal polynomials along meridional direction. Thus, the responses of the shell in wavenumber domain can be naturally obtained. Convergence studies for the theoretical model are conducted by finite element method to verify the reliability of the present method. The vibration behaviors of the coupled model under three typical external loads, including single point force, multiple uniformly spaced point forces, and line force, are studied based on the vibration fields in wavenumber domain. The results indicate that the circumferential modal coupling effect and modal contribution to the total vibrations are sensitive to the types of external excitations, which induces the different vibration behaviors.