Thermomechanical buckling and post-buckling of cylindrical shell with functionally graded coatings and reinforced by stringers

The cylindrical shells reinforced by stringers have been widely used in modern engineering structures such as storage tanks, missile, submarine hull, oil-transmitting pipeline, etc. In this present article, the thermomechanical buckling and post-buckling behaviors of a cylindrical shell with functionally graded (FG) coatings are investigated by an analytical approach. The cylindrical shell is reinforced by outside stringers under torsional load in the thermal environment. The layers of FG coatings are assumed to be made by functionally graded materials (FGMS) combining of ceramic and metal phases and the core of the shell is made from homogeneous material. The classical shell theory based on the von-Karman assumptions is used to model the thin cylindrical shell. Using Galerkin's procedure and Airy stress function, the governing equations can be solved to obtain the closed-form solution for the critical buckling load and postbuckling load-deflection curves of simply supported shells. Moreover, many important parametric studies of stringers, temperature field, material volume fraction index, the thickness of metal layer, etc. are taken into investigation. According to numerical examples, it is revealed that the outside strings have considerably impact on thermomechanical buckling and postbuckling behaviors of the shells.