Deformation of an Open Sandwich Cylindrical Shell with CNT Reinforced Faces Using HDQ Method

In this work, the response of a sandwich cylindrical shell with carbon nanotubes (CNTs)-stiffened faces is investigated under a general distributed static loading. The shell boundaries can exhibit any combination of feasible boundary conditions. Specifically, the faces are made of an isotropic material reinforced with CNTs, while the core is composed of an isotropic material. The faces are modeled as thin cylindrical shells following the Kirchhoff–Love assumptions. Additionally, the in-plane stresses in the core material are assumed to be negligible. The governing equations are derived using the principle of the stationary potential energy. The harmonic differential quadrature method is employed to solve the equations for the deformed components. Subsequently, the obtained results are compared with those from finite element analysis. The maximum discrepancies between the two methods amount to approximately 2%. Next, the effects of various parameters including CNTs incorporation and volume percentage, core flexibility, and the core-to-face thickness ratio on the stress and displacement of sandwich cylindrical shells are explored. Considering all types of boundary conditions and examining the impact of relevant parameters, this study asserts that it represents a comprehensive contribution to the field. The main findings have practical implications for engineers and designers working with cylindrical sandwich shells. Incorporating CNTs into the face sheets, with a V-shaped distribution along the thickness, can significantly alter stress and displacement characteristics. Increasing core thickness, the thickness-to-curvature ratio, the CNT volume percentage, and the Young modulus ratio of face sheets to core reduces transverse displacement at the core mid-surface.