Free Vibration and Flexural Loss Factors of Viscoelastic Laminated Composite Truncated Conical Shells Using Harmonic Differential Quadrature Method

In this paper, the damping and dynamic behavior of laminated composite truncated conical shells with viscoelastic layers are investigated. The viscoelastic properties of the fiber-reinforced plastic composites are modeled using the Kelvin–Voigt viscoelastic model. The shell structure is formulated based on the first-order shear deformation theory. The governing equations and boundary conditions are derived using Hamilton’s variational principle. To compute the natural frequencies and loss factors of the laminated structure, the harmonic differential quadrature method is employed. Furthermore, the effects of various parameters, including the number of face sheet layers, boundary conditions, semi-vertex angle of the cone, circumferential dimensions, width, and thickness, on the vibration response and damping characteristics of the laminated composite truncated conical shells are examined. This study focuses on controlling vibrations in these shells to enhance their service life, with the layers designed to provide effective damping.