Showing papers by "Subrata Kumar Panda published in 2013"

Post-Buckling Analysis of Laminated Composite Doubly Curved Panel Embedded with SMA Fibers Subjected to Thermal Environment

Abstract: In this article, thermal post-buckling of laminated composite panel with SMA subjected to uniform temperature change is investigated. The panel model is derived taking the geometric nonlinearity in Green-Lagrange sense based on the HSDT and then it is extended to incorporate the material nonlinearity arises due to temperature in the SMA via marching technique. The panel is discretized using nonlinear finite element. The system equations are developed by minimizing the total potential energy of the system and solved by a direct iterative method. The effects of different parameters are examined in detail and the results are compared with the published results.

Thermal postbuckling behavior of laminated composite spherical shell panel using NFEM

Abstract: Postbuckling behavior of laminated shell panel in thermal environment is reported in this article. The geometric nonlinearity is introduced in Green–Lagrange sense and the model is developed for the geometrically large translations and/or rotations and the excess thermal deformation of the curved panel based on higher order shear deformation theory (HSDT) using nonlinear finite element. The governing equation of shell panel is derived by minimizing the energy expression. The postbuckling strength in terms of temperature ratio (postbuckling to buckling temperature) of the panel by obtained by a direct iterative method. The results are obtained using the developed model and compared with those of the available published literature. Some of the new results are computed for different parameters such as layup sequences, thickness ratios, amplitude ratios, boundary conditions, aspect ratios, and various curvature ratios and presented.

Large amplitude free vibration analysis of thermally post-buckled composite doubly curved panel embedded with SMA fibers

Abstract: Thermal post-buckled vibration of laminated composite doubly curved panel embedded with shape memory alloy (SMA) fiber is investigated and presented in this article. The geometry matrix and the nonlinear stiffness matrices are derived using Green–Lagrange type nonlinear kinematics in the framework of higher order shear deformation theory. In addition to that, material nonlinearity in shape memory alloy due to thermal load is incorporated by the marching technique. The developed mathematical model is discretized using a nonlinear finite element model and the sets of nonlinear governing equations are obtained using Hamilton’s principle. The equations are solved using the direct iterative method. The effect of nonlinearity both in geometric and material have been studied using the developed model and compared with those published literature. Effect of various geometric parameters such as thickness ratio, amplitude ratio, lamination scheme, support condition, prestrains of SMA, and volume fractions of SMA on the nonlinear free vibration behavior of thermally post-buckled composite flat/curved panel been studied in detail and reported.

Free Vibration Responses of Functionally Graded Spherical Shell Panels Using Finite Element Method

Abstract: Free vibration responses of functionally graded spherical shell panels are investigated in the present article. A general mathematical model is developed based on higher order shear deformation theory mid-plane kinematics. The effective material properties are graded in the thickness direction according to a power-law distribution and it varies continuously from metal (bottom surface) to ceramic (top surface). The model is discretized using a nine noded quadrilateral Lagrangian element. A convergence test has been done with different mesh refinement and compared with the available published results. In addition to that the present study includes an ANSYS model check with the developed mathematical model to show the efficacy. New results are computed for different parameters such as volume fraction, thickness ratio, curvature ratio and support conditions which indicates the effect of parametric study on non-dimensional frequency parameters.© 2013 ASME

Linear Static and Free Vibration Analyses of Laminated Composite Spherical Shells

Abstract: Linear static and free vibration behavior of laminated composite square base spherical shell panel has been investigated using finite element method. The present shell panel model is developed using ANSYS parametric design language code in ANSYS platform. The model is discretised using an eight nodded serendipity element (SHELL281) with six degrees of freedom per node from ANSYS element library. The responses are obtained using Gauss elimination and Block-Lanczos steps for the static and free vibration analysis, respectively. The results are computed using present developed model and the convergence test has also been done. Based on the convergence new results are obtained and compared with published results. The numerical simulations done for different parameters showing that the parameters such as thickness ratios, curvature ratios and lay up sequences have significant effect on transverse central deflections and fundamental free vibration frequencies of the shell structures.© 2013 ASME

Thermo-Mechanical Stability Analysis of Composite Cylindrical Panels

Abstract: In this article, stability behavior of laminated composite curved panels under thermo-mechanical loading is analyzed. A generalized panel model is developed based on higher order shear deformation theory by taking the nonlinearity in Green-Lagrange sense for thermal distortion. The critical buckling load (mechanical/thermal) parameters are obtained by using the developed finite element model validated for both ANSYS and homemade computer code. The model has been discretized in ANSYS using an eight-noded serendipity shell element (shell281) and a nine noded isoparametric element for the computer code. The convergence test has been carried out and the results are compared with those available published literature. In this analysis, a uniform temperature distribution through the thickness is taken and the material properties for the composites are assumed to be temperature invariant. We note substantial effect of different parameters (support conditions, number of layers, thickness ratio and modular ratio) on thermo-mechanical stability behavior of laminated structures.© 2013 ASME