Free vibration analysis of fluid-conveying functionally graded metamaterial subsea cylindrical shells

作者：Zeyu Jiao, Shaoyu Zhao, Yuxin Zhang, Rongqiao Xu, Dong Ruan · 发表于：Thin-Walled Structures · 年份：2025 · DOI：10.1016/j.tws.2025.113793 · 被引用次数：9 · 研究领域：Vibration and Dynamic Analysis、Composite Structure Analysis and Optimization、Structural Analysis and Optimization

This paper proposes a novel functionally graded (FG) graphene origami (GOri)-enabled auxetic metamaterial (GOEAM) cylindrical shell for subsea fluid-conveying applications. The shell structure comprises multiple layers of GOEAM, in which the GOri content varies hierarchically and the GOri folding degree changes continuously along the thickness. The effective material properties of the GOEAM are evaluated using genetic programming (GP)-assisted micromechanical models. Based on the first-order shear deformation shell theory and Hamilton's principle, the governing equations are derived by accounting for the effects of internal fluid flow, external hydrostatic pressure, and elastic foundation. The fluid inside the shell is assumed to be incompressible, inviscid, and irrotational. The Galerkin method is employed to obtain approximate analytical solutions to the governing equations. A comprehensive parametric study is performed to examine the effects of GOri content, GOri folding degree, fluid velocity, length-to-thickness ratio, foundation stiffness, and external hydrostatic pressure on the natural frequencies of FG-GOEAM cylindrical shells. Numerical results demonstrate that the proposed structure exhibits excellent mechanical performance and negative Poisson’s ratio (NPR) behavior, thereby significantly enhancing its vibration characteristics in fluid-transport applications.