Nonlinear frequency and dynamic response of PLA polymeric imperfect FG sandwich plates under hygrothermal conditions
Zuhair Farhan Abo Alhous,Muhsin J. Jweeg,Emad Kadum Njim,Ahmed Mouthanna,Mujtaba A. Flayyih,Royal Madan,Pallavi Khobragade,Praveen Kumar Rai
Abstract
This paper investigates the nonlinear free vibration behavior of porous functionally graded (PFG) sandwich plates under hygrothermal conditions. The material properties of the PFG plates are assumed to change continuously across the thickness governed by the volume fraction of composition. An enhanced rule of mixtures including the distribution of porosity throughout the cross-section was utilized for material modeling. The foundation medium is modeled as nonlinear, homogeneous, and isotropic, which is then solved by using Galerkin's model. The study employs first-order shear deformation theory (FSDT) in the kinematic relations, and the equations of motion are derived using Hamilton's principle. An analytical solution is developed for the PFG sandwich plates, assuming supported boundary conditions. The study thoroughly examines the fundamental natural frequency of PFG plates, considering the impacts of the hygrothermal environment, porosity volume percentage, and span-to-depth ratio. To validate the analytical results, a numerical analysis using finite element method (FEM) is performed using ANSYS software. A maximum discrepancy of 11% was found between the two approaches.
