Thermo-elastic buckling and post-buckling analysis of functionally graded thin plate and shell structures

Mehar²,

Engineering with Computers

et al. 2021

In the present research, finite element solutions of thermal post-buckling load-bearing strength of functionally graded (FG) sandwich shell structures are reported by adopting a higher-order shear deformation type kinematics. For the numerical calculation, nine nodes are considered for each element. A specialized MATLAB code is developed incorporating the present mathematical model to evaluate the numerical buckling temperature. The Green-Lagrange nonlinear strain is adopted for the formulation of the sandwich structure. The eigenvalue equation of the FG sandwich structure is solved to predict the postbuckling temperature values of the structure. Moreover, three kinds of temperature distributions across the panel thickness are assumed, viz., uniform, linear and nonlinear. In addition, the properties are described using the power law distributions. The numerical solutions are first validated and, subsequently, the impact of alterations of structural parameters, viz., the curvature ratios, core-face thickness ratios, support conditions and power law index (n Z ) including the amplitude ratio on the thermal post-buckling response of FG sandwich curved panels have been studied in details. The investigation reveals different interesting outcomes, which may help for future references for the analysis and design of the graded sandwich structure.

“…The validity of buckling temperature obtained via the current HSDT-based approach is examined by comparing the present values with the analytical values reported in [58].…”

Section: Validationmentioning

confidence: 90%

Thermal post-buckling analysis of graded sandwich curved structures under variable thermal loadings

Mehar²,

Engineering with Computers

et al. 2021

Numerical Meth Engineering

“…A numerical integration is required for evaluating the integral in Equation (20). To this purpose, it is convenient to adopt patch-wise integration schemes 44,45 taking into account the high degree of continuity of shape functions.…”

Section: Patch-wise Numerical Integration Over the Mid-surfacementioning

confidence: 99%

A Koiter reduction technique for the nonlinear thermoelastic analysis of shell structures prone to buckling

Liguori

Magisano

Madeo

et al. 2021

The multi-modal Koiter method is a reduction technique for estimating quickly the nonlinear buckling response of structures under mechanical loads requiring a fine discretization. The reduced model is based on a quadratic approximation of the full model using a few linear buckling modes and their second order corrections, followed by the projection of the equilibrium equations onto the modal subspace. In this article, the method is reformulated for geometrically nonlinear thermoelastic analyses of shell structures. The starting point is an isogeometric solid-shell discretization with an accurate modeling of thermal strains, temperature-dependent materials and general temperature distributions. The equilibrium path is defined as a displacement versus temperature amplifier curve, while mechanical loads are kept constant. The strain energy nonlinearity with respect to the temperature amplifier is the main obstacle in the definition of an accurate reduced model. This task is achieved by coherent asymptotic expansions in mixed form using independent stress variables at the integration points and accurate linear buckling modes obtained by a two-point mixed eigenvalue problem. Structures made of isotropic and multi-layered composite materials, including variable angle tow laminates, are considered to show the accuracy of the proposed method.

“…To know the thermal buckling behavior, a numerical investigation was conducted using the proposed formulation. Trabelsi et al [23] studied thermal buckling and post-buckling analysis of functionally graded structures using the Kirchhoff-Love model. The behavior of structure was examined through different numerical examples to know the effectiveness and usefulness of the proposed model.…”

Section: Introductionmentioning

confidence: 99%

Linear Transient Dynamic Analysis of Plates With and Without Cutout

Nayak

Khante

2021

Arab J Sci Eng

The present work exhibits the analysis of a plate with and without cutout considering the dynamic analysis in a transient zone with its application in the civil, structural, and aerospace industry. For this, first-order shear deformable C 0 continuous Finite Element (FE) is implemented to examine transient response of plate. The governing ODE of motion's is integrated using central difference explicit time integration scheme. A lumped mass matrix is obtained by a special diagonlization scheme and the total mass of the element is conserved by inducing effective rotary inertia terms. A FE program is developed based on derived FE formulation to investigate the effect of dynamic loading on such plates. The analysis exhibits the results in terms of displacement, forces, and bending moment of the plate for various aspect ratios and different parameters. The results are shown in terms of tables and graphs for smaller to larger cutout in plates with its different aspect ratio considering transient analysis. The results reveal that transient dynamics analysis shows a considerable difference in the behavior of plates with and without cutout in terms of time period, amplitude, and bending moment than that obtained from static analysis.