Faculty Publications
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Item Vibro-acoustics of functionally graded porous beams subjected to thermo-mechanical loads(Techno-Press, 2022) Mailan Chinnapandi, M.C.L.; Jeyaraj, J.; Eltaher, M.A.This manuscript work presents a comprehensive continuum model capable to investigate the effect of porosity on vibro-acoustic behaviour of functionally graded (FG) beams resting on an elastic foundation subjected to thermal and mechanical loadings. Effects of uniform temperature rise and edge compressive load on the sound radiation characteristics are studied in a comparative manner. The numerical analysis is carried out by combining finite element method with Rayleigh’s integral. Detailed parametric studies are accomplished, and influences of power law index, porosity volume, porosity distribution and boundary conditions on the vibro-acoustic response characteristics are analyzed. It is found that the vibroacoustic response under mechanical edge compression is entirely different compared to from that under the thermal load. Furthermore, nature of grading of porosity affects the sound radiation behaviour for both the loads. The proposed model can be used to obtain the suppression performance of vibration and noise FG porous beams under thermal and mechanical loads. © © 2022 Techno-Press, Ltd.Item Buckling and vibration of beams using Ritz method: Effects of axial grading of GPL and axially varying load(Taylor and Francis Ltd., 2024) Patil, H.H.; Jeyaraj, J.; Eltaher, M.A.The present work discusses buckling and vibration characteristics of axially functionally graded (AFG) graphene platelet (GPL) composite beams exposed to axially varying loads (AVLs). Timoshenko beam composition with five different types of axial grading GPLs subjected to six different types of AVLs are studied. The effective elastic properties are obtained using Halpin-Tsai model and the equations of motion are obtained following the Hamilton’s principle. Then the equations are solved for buckling and vibration analysis using the Ritz method. Influences of nature of axial grading of GPLs and load, content of GPL, and structural boundary conditions are investigated through detailed parametric studies. It is found that the grading pattern of GPLs not only influences the buckling load, but also changes buckling mode shapes of the beam at specific type of AVL. Furthermore, results reveal that buckling and vibration characteristics of beam enhanced in case of AFGM-A type for most of the load cases studied. The proposed study will be helpful for the structural engineers to select the nature of graded distribution of GPLs for the given type of AVL and design the structural member. © 2023 Taylor & Francis Group, LLC.Item Applicability Two-Dimensional Differential Integral Quadrature Method in Vibration Analysis of Multi-Directional Functionally Graded Porous Viscoelastic Plates(John Wiley and Sons Ltd, 2025) Mohamed, S.A.; Mohamed, N.; Assie, A.E.; Eltaher, M.A.; Pitchaimani, J.; Abo-Bakr, R.This study formulates a differential integral quadrature method (DIQM) to analyze the free vibration characteristics of multi-directional functionally graded material (MFGM) viscoelastic porous plates. The kinematic relations are derived using a unified shear deformation plate theory, while material behavior is governed by the integer-order Kelvin-Voigt viscoelastic constitutive model. Power-law functions define the spatial gradation of material constituents along the length, width, and thickness directions. Two distinct porosity distributions are incorporated to characterize void and cavity variations through the plate's thickness. Hamilton's variational principle yields five coupled governing equations expressed as partial differential equations with variable coefficients. The differential quadrature method (DQM) discretizes these governing equations, with integral quadrature method (IQM) efficiently resolving the variable coefficients. This discretization results in an algebraic system constituting a quadratic eigenvalue problem. The eigenvalues' real and imaginary components provide the damping coefficients and natural frequencies, respectively. The proposed model and solution methodology are validated against established unified shear formulations, MFGM porous plates, and viscoelastic plate solutions available in literature. Comprehensive parametric studies systematically investigate the influence of material gradation indices, porosity parameters, boundary conditions, and viscoelastic coefficients on the natural vibration response of thick MFGM viscoelastic porous plates. The results demonstrate that an increase in either of the material gradation indices leads to a decrease in both of the real and imaginary parts of the fundamental frequencies. © 2025 John Wiley & Sons Ltd.