Vibro-Acuostic Response Analysis of Laminated Composite Multi-Stepped Cylindrical Shells Immersed in Fluid Medium.

Purpose: In this paper, the vibro-acoustic characteristics of laminated composite multi-stepped cylindrical shells immersed in fluid medium are investigated. Method: The first order shear deformation theory (FSDT) and the variational principles are applied to formulate the vibration model and the Kirchhoff–Helmholtz integral equation is employed to analyze the acoustic characteristics of the laminated composite multi-stepped cylindrical shells. The displacement field of the structure are expanded by Jacobi polynomials for vibration analysis and the Chebyshev polynomials for acoustic analysis are used. A set of Chebyshev collocation points are used to formulate the algebraic system of the acoustic integral equations, and the CHIEF method is used to solve the non-uniqueness problem. Results: Numerical results are given for vibration analyses and acoustic characteristics analyses of the laminated composite multi-stepped cylindrical shells. The accuracy and reliability of the present method is verified by comparing with results obtained by references and the coupled finite element method/boundary element method (FEM/BEM). Then, the influence of the geometric, material properties, boundary condition, fluid medium and force types on vibro-acoustic behaviors of the laminated composite multi-stepped cylindrical shells is provided through several numerical examples. [ABSTRACT FROM AUTHOR]