Free Vibration Analysis of Laminated Sandwich Spherical Shell With Viscoelastic Core by using Ultraspherical Polynomial

In this paper, the free vibration behavior of laminated sandwich spherical shell with viscoelastic core are presented. Based on the first order shear deformation theory (FSDT), the theoretical formulations for analyzing the free vibration of the laminated sandwich spherical shell are established. The displacement components of the viscoelastic core are expressed as those of base and constraining layers by using continuity condition. The displacement fields of the laminated sandwich spherical shell are expanded by the Ultraspherical polynomials in meridional direction and Fourier series in circumferential directions. The accuracy and reliability of the presented method on the free vibration of laminated sandwich spherical shell with viscoelastic core are verified by comparing to the vibrational analysis results of published literatures and finite element software ABAQUS. Finally, the effects of some parameters on the frequency parameters and modal loss factors of the laminated sandwich spherical shell are presented, which contributes to the preliminary design of the laminated sandwich spherical shell with viscoelastic core.