Comparative study of different porosity models for the nonlinear free vibration analysis of the functionally graded cylindrical panels

Abstract

This study presents a comparative analysis of the linear and nonlinear vibrations of the shear deformable functionally graded (FG) cylindrical panels for the proposed porosity distribution model with existing porosity models. The higher-order shear deformation nonlinear shell theory is applied to formulate the nonlinear finite element model considering von Karman type nonlinearity. The mechanical properties of the proposed porosity distribution model are continuously varying in the thickness direction according to a modified power-law relationship in terms of constituents’ volume fractions. A convergence and comparative studies are performed to validate the proposed nonlinear formulation for various porosity distributions. Parametric studies are carried out to investigate the effect of various influencing factors on the linear frequency parameters as well as nonlinear frequency ratios of the FG cylindrical panels i.e., porosity indices, volume fraction indices, porosity distributions, and other geometric parameters. When the proposed porosity distribution model is compared to existing porosity distribution models (even and uneven distributions), it is observed that the proposed model is more suited to FG porous structures with higher ceramic content.