Faculty Publications

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    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.
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    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 Ltd
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    Vibration control of multiferroic fibrous composite plates using active constrained layer damping
    (Academic Press, 2018) Kattimani, S.; Ray, M.C.
    Geometrically nonlinear vibration control of fiber reinforced magneto-electro-elastic or multiferroic fibrous composite plates using active constrained layer damping treatment has been investigated. The piezoelectric (BaTiO3) fibers are embedded in the magnetostrictive (CoFe2O4) matrix forming magneto-electro-elastic or multiferroic smart composite. A three-dimensional finite element model of such fiber reinforced magneto-electro-elastic plates integrated with the active constrained layer damping patches is developed. Influence of electro-elastic, magneto-elastic and electromagnetic coupled fields on the vibration has been studied. The Golla–Hughes–McTavish method in time domain is employed for modeling a constrained viscoelastic layer of the active constrained layer damping treatment. The von Kármán type nonlinear strain-displacement relations are incorporated for developing a three-dimensional finite element model. Effect of fiber volume fraction, fiber orientation and boundary conditions on the control of geometrically nonlinear vibration of the fiber reinforced magneto-electro-elastic plates is investigated. The performance of the active constrained layer damping treatment due to the variation of piezoelectric fiber orientation angle in the 1–3 Piezoelectric constraining layer of the active constrained layer damping treatment has also been emphasized. © 2018 Elsevier Ltd
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    Neural network-based prediction model to investigate the influence of temperature and moisture on vibration characteristics of skew laminated composite sandwich plates
    (MDPI AG, 2021) Kallannavar, V.; Kattimani, S.; Soudagar, M.E.M.; Abbas, M.A.; Alshahrani, S.; Imran, M.
    The present study deals with the development of a prediction model to investigate the impact of temperature and moisture on the vibration response of a skew laminated composite sandwich (LCS) plate using the artificial neural network (ANN) technique. Firstly, a finite element model is generated to incorporate the hygro-elastic and thermo-elastic characteristics of the LCS plate using first-order shear deformation theory (FSDT). Graphite-epoxy composite laminates are used as the face sheets, and DYAD606 viscoelastic material is used as the core material. Non-linear strain-displacement relations are used to generate the initial stiffness matrix in order to represent the stiffness generated from the uniformly varying temperature and moisture concentrations. The mechanical stiffness matrix is derived using linear strain-displacement associations. Then the results obtained from the numerical model are used to train the ANN. About 11,520 data points were collected from the numerical analysis and were used to train the network using the Levenberg– Marquardt algorithm. The developed ANN model is used to study the influence of various process parameters on the frequency response of the system, and the outcomes are compared with the results obtained from the numerical model. Several numerical examples are presented and conferred to comprehend the influence of temperature and moisture on the LCS plates. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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    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.
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    Effect of porosity on active damping of geometrically nonlinear vibrations of a functionally graded magneto-electro-elastic plate
    (China Ordnance Industry Corporation, 2022) Esayas, L.S.; Kattimani, S.
    This paper investigates the effect of porosity on active damping of geometrically nonlinear vibrations (GNLV) of the magneto-electro-elastic (MEE) functionally graded (FG) plates incorporated with active treatment constricted layer damping (ATCLD) patches. The perpendicularly/slanted reinforced 1–3 piezoelectric composite (1–3 PZC) constricting layer. The constricted viscoelastic layer of the ATCLD is modeled in the time-domain using Golla-Hughes-McTavish (GHM) technique. Different types of porosity distribution in the porous magneto-electro-elastic functionally graded PMEE-FG plate graded in the thickness direction. Considering the coupling effects among elasticity, electrical, and magnetic fields, a three-dimensional finite element (FE) model for the smart PMEE-FG plate is obtained by incorporating the theory of layer-wise shear deformation. The geometric nonlinearity adopts the von Kármán principle. The study presents the effects of a variant of a power-law index, porosity index, the material gradation, three types of porosity distribution, boundary conditions, and the piezoelectric fiber's orientation angle on the control of GNLV of the PMEE-FG plates. The results reveal that the FG substrate layers' porosity significantly impacts the nonlinear behavior and damping performance of the PMEE-FG plates. © 2021 China Ordnance Society
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    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.
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    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.
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    Influence of hybrid smart damping system on bi-directionally tapered functionally graded plate using 1-3 PZC resting on winkler-pasternak flexible support
    (SAGE Publications Inc., 2025) Shada, S.K.; Kattimani, S.; Ramesh, M.R.
    This article presents a numerical investigation of free vibrational features of bi-directionally tapered functionally graded (BTFG) plate unified with active constrained layer damping (ACLD) on a two-parameter Winkler-Pasternak flexible support. In conjunction with the virtual work principle, the first-order shear theory for deformation is employed. The plate’s damping is actively controlled using a velocity feedback control system with 1-3 piezoelectric patches consisting of piezoelectric and viscoelastic layers. Effects of foundation/support parameters (Kw and Ks), taper ratios, ACLD patch placement, and boundary conditions are systematically analysed through frequency response studies. Results demonstrate that incorporating ACLD patches significantly enhances damping features. Revealing with edge patch placement yields superior vibration suppression on the substrate plate. The study highlights the synergistic impact of ACLD patches, flexible supports, and active control, presenting a robust solution for precision vibration control in advanced structural applications. © The Author(s) 2025