Vibration Analysis of Partially Fluid-filled Graphene-nanoplatelet-reinforced Sandwich Cylindrical Shells with Porous Core

The study investigates the vibration characteristics of partially fluid-filled sandwich cylindrical shells with a porous core. The refined shear deformation theory is adopted for theoretical analysis to account for the transverse shear deformation. The shells are reinforced with graphene nanoplatelets. The core comprises closed-cell foam, with pores being distributed in various patterns along the thickness direction. The fluid is described by the deformation potential for the coupled fluid-structure interaction. The governing eigenvalue equation is obtained using the Rayleigh-Ritz method. Comparison with previously reported methods highlights the reliability of the proposed approach. Parametric studies are conducted on dimensionless natural frequencies. The effects of the graphene nanoplatelets, pores, and especially fluids on the vibration characteristics are studied. Furthermore, the 3D vibration mode-shapes are presented for various fluid-filled levels.