Vibration analysis of a sandwich cylindrical shell in hygrothermal environment

Abstract

The sandwich structures are three- or multilayered structures such that their mechanical properties are better than each single layer. In the current research, a three-layered cylindrical shell including a functionally graded porous core and two reinforced nanocomposite face sheets resting on the Pasternak foundation is used as model to provide a comprehensive understanding of vibrational behavior of such structures. The core is made of limestone, while the epoxy is utilized as the top and bottom layers’ matrix phase and also it is reinforced by the graphene nanoplatelets (GNPs). The pattern of the GNPs dispersion and the pores distribution play a crucial role at the continuous change of the layers’ properties. The sinusoidal shear deformation shells theory and the Hamilton’s principle are employed to derive the equations of motion for the mentioned cylindrical sandwich shell. Ultimately, the impacts of the model’s geometry, foundation moduli, mode number, and deviatory radius on the vibrational behavior are investigated and discussed. It is revealed that the natural frequency and rotation angle of the sandwich shell are directly related. Moreover, mid-radius to thickness ratio enhancement results in the natural frequency reduction. The results of this study can be helpful for the future investigations in such a broad context. Furthermore, for the pipe factories current study can be effective at their designing procedure.

Green energy harvesting strategies on edge-based urban computing in sustainable internet of things

“…It is an arrangement of technology that efficiently handles existing as well as new transportation systems, improving operational effectiveness, gaining protection, and reducing the transport demands of people at a low and efficient charge. It additionally gives a unique strategy in implementing various forms of transport, improved support, and more qualified traffic control solutions (Zhang et al, 2021).…”

On the large amplitude vibration of shallow sandwich shells with FG-GNPRP core considering initial geometric imperfections

“…because they provide relatively high flexural stiffness with a very little gain in the weight of entire structure. [1][2][3][4][5] In order to lighten the sandwich structures and provide a better energy absorption capability, the porosity can be considered throughout the core. [6][7][8] However, such laminated sandwich structures may face delamination, matrix-fiber debonding, matrix cracking, etc.…”