Conference Papers

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    Free vibration analysis of single and multilayered sandwich FGM plates-assessment of higher order refined theories
    (2014) Swaminathan, K.; Naveenkumar, D.T.
    Analytical formulations and solutions for natural frequency analysis of functionally graded material (FGM) plates based on two higher-order refined shear deformation theories with 9 and 12 degrees-of-freedom are presented. The displacement model with 12 degrees-of-freedom considers the effect of both transverse shear and normal strain/stress while the other considers only the effect of transverse shear deformation. In addition another higher-order model and the firstorder model developed by other investigators and available in the literature are also presented for the evaluation purpose. For mathematical modeling purposes, the Poisson's ratio of the material is considered as constant whereas Young's modulus is assumed to vary through the thickness according to the power law function. The equations of motion are derived using Hamilton's principle. Solutions are obtained in closed-form using Navier's technique and solving the eigenvalue equation. The accuracy of the theoretical formulations and the solution method using the present two higher-order refined models is first established by comparing the results generated in the present investigation with the 3D elasticity solutions already reported in the literature. After establishing the accuracy of predictions, benchmark results for the natural frequencies using all the four models are presented for single layer FGM plate and multi layered FGM sandwich plate with varying edge ratios and side-to-thickness ratios. © (2014) Trans Tech Publications, Switzerland.
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    Free Vibration Characteristics of Banana/Sisal Natural Fibers Reinforced Hybrid Polymer Composite Beam
    (Elsevier Ltd, 2016) RAJESH, M.; Jeyaraj, P.; Nagarajan, N.
    Natural fibers having more advantage compared to man-made fiber, such as glass, carbon, Kevlar fiber. But due to the hydrophilic nature of natural fiber gives poor adhesion between fiber-matrix. This will decrease the properties of polymer composite. In this study influence of surface pre-treatment with sodium hydroxide and hybridization effect of natural fiber are investigated on flexural test and free vibration behavior. In this work sisal and banana natural fibers are used in short and random orientations to prepare the polymer composites using compression moulding method. From the experimentation, it is found that chemical treatment improves the mechanical and free vibration properties of polymer composites due to the enhancement of interfacial bond between fiber and matrix as the result of chemical treatment. © 2016 The Authors.
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    Buckling and Free Vibration Characteristics of a Uniformly Heated Isotropic Cylindrical Panel
    (Elsevier Ltd, 2016) Bhagat, V.; Jeyaraj, P.; Murigendrappa, S.M.
    In this paper buckling and free vibration characteristics of an isotropic cylindrical panel subjected to uniform temperature rise has been investigated using finite element method. The procedure involves the determination of critical buckling temperature, which is followed by modal analysis considering pre-stress due to the thermal field in the cylindrical panel. Detailed studies are carried out to analyze the influence of curvature ratio, thickness ratio and aspect ratio on the critical buckling temperature and free vibration behavior of an isotropic cylindrical panel. It has been found that as the curvature ratio and the thickness ratio increases the thermal buckling strength of the cylindrical panel decreases. It has also been found that free vibration frequencies reduce with an increase in temperature and the reduction is more significant for the lowest frequency mode. It is observed that free vibration mode shapes at ambient temperature changes with an increase in temperature. © 2016 The Authors.
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    Buckling and Free Vibration Behavior of a Temperature Dependent FG-CNTRC Cylindrical Panel under Thermal Load
    (Elsevier Ltd, 2018) Bhagat, V.; Jeyaraj, P.; Murigendrappa, S.M.
    Present study deals with the buckling and free vibration behavior of functionally graded carbon-nanotubes reinforced composite (FG-CNTRC) cylindrical panel exposed to uniform thermal load. Stresses setup due to thermal load and temperature dependent properties influences the buckling and free vibration behavior of the heated structures. Approach employed in the present study consists of static analysis to compute thermal stresses, eigen-value buckling analysis to compute critical buckling temperature and finally modal analysis, taking thermal stresses into account. Influence of different CNTs grading pattern, CNTs volume fraction, geometric parameters, boundary constraints and temperature dependent properties on the buckling strength are investigated. It is observed that hybrid CNTs distribution pattern gives comparatively higher buckling strength and free vibration frequencies. Investigation on free vibration characteristics of the FG-CNTRC panel at elevated temperature signifies that the decline in free vibration frequencies is very drastic at a temperature close to buckling temperature along with temperature dependent properties. c 2017 Elsevier Ltd. All rights reserved. © 2018 Elsevier Ltd.