Faculty Publications
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Item Influence of coupled fields on free vibration and static behavior of functionally graded magneto-electro-thermo-elastic plate(SAGE Publications Ltd info@sagepub.co.uk, 2018) Mahesh, M.; Sagar, P.J.; Kattimani, S.In this article, the influence of full coupling between thermal, elastic, magnetic, and electric fields on the natural frequency of functionally graded magneto-electro-thermo-elastic plates has been investigated using finite element methods. The contribution of overall coupling effect as well as individual elastic, piezoelectric, piezomagnetic, and thermal phases toward the stiffness of magneto-electro-thermo-elastic plates is evaluated. A finite element formulation is derived using Hamilton’s principle and coupled constitutive equations of magneto-electro-thermo-elastic material. Based on the first-order shear deformation theory, kinematics relations are established and the corresponding finite element model is developed. Furthermore, the static studies of magneto-electro-elastic plate have been carried out by reducing the fully coupled finite element formulation to partially coupled state. Particular attention has been paid to investigate the influence of thermal fields, electric fields, and magnetic fields on the behavior of magneto-electro-elastic plate. In addition, the effect of pyrocoupling on the magneto-electro-elastic plate has also been studied. Furthermore, the effect of geometrical parameters such as aspect ratio, length-to-thickness ratio, stacking sequence, and boundary conditions is studied in detail. The investigation may contribute significantly in enhancing the performance and applicability of functionally graded magneto-electro-thermo-elastic structures in the field of sensors and actuators. © 2017, © The Author(s) 2017.Item Porosity influence on structural behaviour of skew functionally graded magneto-electro-elastic plate(Elsevier Ltd, 2018) Kiran, M.C.; Kattimani, S.; Mahesh, M.This article presents a finite element (FE) formulation to assess the influence of porosity on the static responses and free vibration of functionally graded skew magneto-electro-elastic (FGSMEE) plate. The porosity is accounted for local density using modified power law. The skew edges of the plate are achieved by implementing transformation matrix. The coupled constitutive relations establish the different couplings associated with MEE materials. The displacements, potentials, and stresses for the porous skew plate are established through static analysis. The influence of porosity on the natural frequency of the skew plate is investigated via free vibration analysis. The influence of different porosity distributions on various skew angles of the FGSMEE plate has been studied. The effect of porosity volume, skew angle, and geometrical parameters such as aspect ratio, thickness ratio, and boundary conditions on the porous FGSMEE plate is investigated. © 2018 Elsevier LtdItem Nonlinear free vibration and transient responses of porous functionally graded magneto-electro-elastic plates(Springer Science and Business Media Deutschland GmbH, 2022) Sh, E.L.; Kattimani, S.; Mahesh, M.The geometrically nonlinear free vibration and transient response of porous functionally graded magneto-electro-elastic (PFG-MEE) plates are studied based on the first-order shear deformation (FSDT) theory, von Karman's nonlinear strain–displacement relations along with modified power law. With Hamilton's theory, the coupled equations of motion are obtained and analyzed by adapting finite element methods (FEM). Moreover, using Newmark's, Picard's, and Newton–Raphson methods, a porous FG-MEE plate's nonlinear and transient response is analyzed using MATLAB software. After validating the present study, the influence of porosity distribution, porosity index, boundary conditions, aspect ratios, and thickness to length ratios on the nonlinear frequency ratio and nonlinear transient response of porous FG-MEE plate is investigated. It is revealed that geometric parameters, porosity index, boundary conditions, and form of porosity distribution significantly influence the nonlinear frequency ratio and nonlinear transient deflections of porous FG-MEE plates. © 2021, Wroclaw University of Science and Technology.Item Nonlinear analysis of two-directional functionally graded doubly curved panels with porosities(Techno-Press, 2022) Naveen Kumar, H.S.; Kattimani, S.This article investigates the nonlinear behavior of two-directional functionally graded materials (TDFGM) doubly curved panels with porosities for the first time. An improved and effectual approach is established based on the improved first-order shear deformation shell theory (IFSDST) and von Karman’s type nonlinearity. The IFSDST considers the effects of shear deformation without the need for a shear correction factor. The composition of TDFGM constitutes four different materials, and the modified power-law function is employed to vary the material properties continuously in both thickness and longitudinal directions. A nonlinear finite element method in conjunction with Hamilton’s principle is used to obtain the governing equations. Then, the direct iterative method is incorporated to accomplish the numerical results using the frequency-amplitude, nonlinear central deflection relations. Finally, the influence of volume fraction grading indices, porosity distributions, porosity volume, curvature ratio, thickness ratio, and aspect ratio provides a thorough insight into the linear and nonlinear responses of the porous curved panels. Meanwhile, this study emphasizes the influence of the volume fraction gradation profiles in conjunction with the various material and geometrical parameters on the linear frequency, nonlinear frequency, and deflection of the TDFGM porous shells. The numerical analysis reveals that the frequencies and nonlinear deformations can be significantly regulated by changing the volume fraction gradation profiles in a specified direction with an appropriate combination of materials. Hence, TDFGM panels can overcome the drawbacks of the functionally graded materials with a gradation of properties in a single direction. © © 2022 Techno-Press, Ltd.Item Geometrically nonlinear behavior of two-directional functionally graded porous plates with four different materials(SAGE Publications Ltd, 2022) Hosur Shivaramaiah, N.K.; Kattimani, S.; Shariati, M.; Nguyen, T.This article investigates the influence of porosity distributions on the nonlinear behavior of two-directional functionally graded porous plates (TDFGPP) made from four distinct materials for the first time. A simple and effectual approach is established based on the improved generalized shear deformation plate theory (GSDPT) and von Karman’s assumptions. The GSDPT incorporates transverse shear strains with a higher order polynomial to avoid shear locking. The TDFGPP constitutes four different materials, and the modified power-law function is employed to vary the material properties continuously in both transverse and longitudinal directions. The governing equations are obtained using a nonlinear finite element approach in conjunction with Hamilton’s principle. Then, the direct iterative and Newmark’s methods are incorporated to accomplish the numerical results. Finally, the influence of volume fraction grading indices, porosity distributions, porosity volume, thickness ratio, and aspect ratio for different support conditions provides a thorough insight into the linear and nonlinear responses of the porous plate. In addition, this study emphasizes the influence of the volume fraction gradation profiles with four different materials on the linear frequency, nonlinear frequency, and deflections of the TDFGPP. The numerical analysis reveals that the frequencies and nonlinear deformations can be significantly regulated by changing the volume fraction gradation profiles in specified directions with appropriate materials. Hence, two-directional functionally graded materials panels can overcome the drawbacks of the functionally graded materials with a gradation of properties in a single direction. © IMechE 2022.Item Static, buckling, and free vibration characteristics of porous skew partially functionally graded magneto-electro-elastic plate(Taylor and Francis Ltd., 2023) Kiran, K.; Wang, W.; Fang, C.; Kattimani, S.In this article, a new mathematical model to develop porous skew partially functionally graded (SPFG) magneto-electro-elastic (MEE) plate from a stepped functionally grade (SFG) plate is proposed. The combination of Barium Titanate (BaTiO3) and Cobalt Ferrite (CoFe2O4) is graded stepwise to achieve SFG plates. Such, SFG plate is approximated using modified power law for functional variation through its thickness. Modified first-order shear deformation theory (FSDT) is deployed in the current study to develop mathematical models. The geometrical modification from rectangular to skew plate is achieved using transformation matrix. Porosity in the partial functionally graded MEE plate is taken as local density. Free vibration study is carried out to reflect the influence of partial gradation, porosity distribution, porosity volume, and skew angle on the natural frequency of porous SPFG MEE plate. The influence of various types of porosity distribution, partial gradation, and skew angle on the primary quantities such as displacements, potentials, and secondary quantities such as stresses, electric displacement, and magnetic induction on SPFG MEE plate is studied. The stability characteristics of the SPFG MEE plate are also investigated to study the buckling behavior under various porosity distributions, partial gradation, and skew angles. The effect of change in aspect ratio, and thickness ratio on the free vibration and static behavior is also investigated. © 2021 Taylor & Francis Group, LLC.Item Geometrically Nonlinear Study of Functionally Graded Saturated Porous Plates Based on Re¯ned Shear Deformation Plate Theory and Biot's Theory(World Scientific, 2023) Kumar, H.S.N.; Kattimani, S.; Marques, F.D.; Nguyen, T.; Shariati, M.This research presents the geometrically nonlinear investigation of functionally graded saturated porous material (FGSPM) plate under undrained conditions. In conjunction with von Karman's nonlinearity, the re¯ned shear deformation plate theory (RSDPT) is implemented to model the FGSPM plate. The e®ective material characteristics of the saturated porous plate change constantly in the thickness direction. The pores of the saturated porous plate are examined in °uid-¯lled conditions. Thus, the constitutive equations are established using Biot's linear poroelasticity theory. The governing equations are developed by combining a nonlinear ¯nite element technique with Hamilton's principle. Then, the direct iterative approach is utilized to extract the geometrically nonlinear numerical results. The emphasis is placed on exploring the e®ects of numerous parameters such as Skempton coe±cient, volume fraction grading index, porosity volume index, porosity distributions, and boundary conditions during the extensive numerical analyses on the linear frequency, large amplitude frequencies, and nonlinear central de°ections of the FGSPM plate. It is evident from the investigation that saturated °uid in the pores substantially impacts the nonlinear de°ection and vibration behavior of the FGSPM plate. © World Scientic Publishing Company.Item Active layer damping of bi-directionally tapered functionally graded sandwich plates with 1-3 piezoelectric composites(Taylor and Francis Ltd., 2024) Shada, S.K.; Kattimani, S.; M.r, R.This article investigates the effect of smart damping on bi-directionally tapered functionally graded sandwich plates. The substrate comprises FG material on both sides of the core of either soft herex or ceramic material. The viscoelastic layer of ALD is restrained, while the compelling layer consists of 1-3PZC. The finite element formulation developed incorporates layer-wise and first-order-shear-deformation theory. The plate’s damping is actively controlled using velocity feedback control incorporating piezoelectric patches. The effects of various parameters of taper ratio and patch positions on vibration control are investigated. The efficacy of the ALD in improving the structural performance of plates is investigated. © 2024 Taylor & Francis Group, LLC.Item An electromechanical coupling isogeometric approach using zig-zag function for modeling and smart damping control of multilayer PFG-GPRC plates(Springer, 2024) Nguyen, T.; Ly, D.-K.; Kattimani, S.; Thongchom, C.In this article, a novel numerical approach based on electromechanical coupling isogeometric analysis employing a piecewise linear zig-zag function is proposed for modeling and analysis of smart constrained layer damping (SCLD) treatment in multilayer porous functionally graded graphene platelets-reinforced composite (PFG-GPRC) plates. The approach efficiently approximates the geometric, mechanical, and electric displacement fields by utilizing non-uniform rational B-splines (NURBS) basis functions. These basis functions are subsequently integrated with the zig-zag formulation to characterize the system dynamic and help handle both continuous/discontinuous material properties at all interfaces, as well as improve the effectiveness of global–local numerical solutions for the analysis of current structures. The multilayer PFG-GPRC plate model is designed to incorporate porous, uniformly, or non-uniformly distributed layers based on three different graphene platelet patterns. The analysis of the SCLD treatment encompasses an examination of the frequency response function of the damped structure under passive/hybrid mechanisms, taking into account viscoelastic behavior and the converse piezoelectric effect. Reliability in the current analysis is demonstrated through a validation study, and a comprehensive parametric investigation is undertaken to analyze the impact of various parameters related to graphene platelets (GPLs) and distribution types of porosity on the damping behavior of multilayer PFG-GPRC plates. © The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2023.Item Influence of saturated porosity distributions on the geometrically nonlinear behavior of functionally graded porous plates in a thermal environment(Springer Science and Business Media Deutschland GmbH, 2025) Kumar, H.S.N.; Kattimani, S.; Lingaraju, S.V.; Dhuttargaon, M.S.; Gidaveer, S.M.The nonlinear vibration behavior of functionally graded saturated porous (FGSP) plates in thermal environments is a complex problem influenced by material gradients, pore saturation, and temperature effects. Accurately capturing the impact of saturated porosity distributions and geometric nonlinearity on the dynamic behavior of these plates presents a key challenge. This study investigates the linear and nonlinear vibration characteristics of FGSP plates under thermal gradients, focusing on the role of saturated porosities. A modified power-law defines the temperature-dependent effective material properties through the plate’s thickness, while Biot’s theory models the effects of saturated pores. The governing equations are developed using the refined shear deformation plate theory combined with von Karman’s nonlinear relations and Hamilton’s principle. Numerical simulations via the direct iterative model provide insights into the linear and large-amplitude frequencies and the nonlinear central deflection of FGSP plates. Results indicate that saturated fluids within the pores significantly affect both vibrational frequencies and deflections, emphasizing the importance of considering porosity and thermal effects in modeling. This study highlights the necessity of incorporating saturated porosities and temperature-dependent properties for precise performance prediction, offering valuable guidance for designing porous materials in thermomechanical applications. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.