Thermal Buckling Optimization of Composite Laminates by Evolution Strategies (original) (raw)

Optimization of laminated composite plates subjected to nonuniform thermal loads

Polymers and Polymer Composites, 2019

Fiber-reinforced laminated composite structures are extensively used in aircraft and aerospace industries for their high specific strength and stiffness. In such applications, they are generally subjected to nonuniform thermal loads due to change in thermal conditions. Therefore, the composite structures used in the applications in which they are subjected to nonuniform thermal loads must also be designed to withstand thermal loads. As mechanical and thermal properties of fiber-reinforced laminated composites are greatly influenced by the direction of fibers and stacking sequences, they are optimally varied in this article to maximize the critical buckling temperature of the composite plate. The ply angle and stacking sequence of the laminated composite plate are optimized using genetic algorithm to maximize the thermal buckling temperature. As the plate is subjected to different kinds of nonuniform thermal load cases, finite element technique is used to analyze the plate during the optimization process. As geometry and supporting conditions of the plate also have great influence on its thermal buckling strength, the investigation is further widened by carrying out the optimization process for the plate model constructed with various types of support conditions, aspect ratio, and nonuniform load cases. The numerical results clearly show the necessities that the optimum ply angle and stacking sequences are greatly varying based on the aspect ratio, support conditions, and nonuniform loading cases.

Multi-objective optimization of buckling load for a laminated composite plate by coupling genetic algorithm and FEM

2018

In this paper, a combination method has been developed by coupling Multi-Objective Genetic Algorithms (MOGA) and Finite Element Method (FEM). This method has been applied for determination of the optimal stacking sequence of laminated composite plate against buckling. The most important parameters in optimization of a laminated composite plate such as, angle, thickness, number, and material of each layer are considered in the proposed method. These optimization processes have done for 3 types of compressive loads and optimal stacking sequences and Pareto front for each kind of compressive loads are determined. Unlike estimation methods like response surface and simple analytic methods, in the proposed optimization algorithm, objective functions are calculated directly by FEM software which leads to precise results. The results of proposed algorithm are validated against existing data in literature. The effects of different boundary conditions and aspect ratio of plate on Pareto fron...

Thermal buckling load optimization of laminated composite plates

Thin-Walled Structures, 2008

New numerical results are generated for in-plane compressive biaxial buckling which serve to quantify the effects of lamination scheme on buckling loading. The results indicate that the symmetric laminate is stiffer than the anti-symmetric one. This phenomenon is caused by coupling between bending and stretching which lowers the buckling loads of symmetric laminate.

Optimum Design of Composite Plates under Thermal Buckling Loads using Imperialist Competitive Algorithm

Thermal buckling loads of laminated composite plates are maximized for a given total thickness. Fiber directions and relative thickness of layers are considered as design variables. Analysis of buckling temperature is carried out by using the finite element method, while the imperialist competitive algorithm (ICA) is employed to optimize as many as seven variables for the different layered plates. The imperialist competitive algorithm (ICA) is thus evaluated for its recognition.

Buckling optimization of composite laminates using a hybrid algorithm under Puck failure criterion constraint

Journal of Reinforced Plastics and Composites, 2016

In this study, an optimization procedure is proposed to find the optimum stacking sequence designs of laminated composite plates in different fiber angle domains for maximum buckling resistance. A hybrid algorithm combining genetic algorithm and trust region reflective algorithm is used in the optimization to obtain higher performance and improve the quality of solutions. As a novelty, Puck fiber and inter-fiber failure criteria are directly implemented to the optimization problems as nonlinear function constraints, which have allowed more consistent and feasible results. The performance of the hybrid algorithm is demonstrated by comparing with the individual performances of genetic and trust region reflective algorithms via test problems from the literature. Also, a study is performed to exhibit the effectiveness of the selected failure criterion as constraint among the other common criteria. The proposed procedure is used to solve many problems including various design considerati...

A comparative analysis of evolutionary algorithms in the design of laminated composite structures

Science and Engineering of Composite Materials, 2017

The increased use of composite materials and structures in many engineering applications led to the need for a more accurate analysis and design optimization. While methods of stress-strain analysis developed faster, optimization techniques have been lagging behind. As a result, many designed structures do not fulfill their full potential. The present study demonstrates the major achievements in recent years in an application of evolutionary algorithms to the design optimization of fiber-reinforced laminated composite structures. Such structures are of much interest due to high structural design sensitivity to fiber orientations as well as complex multidimensional discrete optimization problems. Using an anisotropic multilayered cylindrical pressure vessel and an exact elasticity solution as an example, we show how the optimum, or near–optimum, solution can be found in a more efficient way.

Multiconstrained optimization of laminated and sandwich plates using evolutionary algorithms and higher-order plate theories

Composite Structures, 2003

The optimization of laminated and sandwich plates with respect to buckling load and thickness has been performed, using different sets of constraints such as the fundamental frequency, the maximum deflection under transverse uniform distributed load, the mass and the buckling load. Two different evolutionary algorithms have been employed (genetic algorithm and simulated annealing (SA)) together with two plate models (classical plate theory and cubic zig-zag model). The performed analyses show that the two evolutionary algorithms provide almost the same results though the SA procedure is less time consuming; furthermore, results of the two displacement theories are the closer to each other the higher the side-to-thickness ratio is.

Buckling Load Maximization of Laminated Composite Plates

2017

In the present study, buckling load carrying capacity of laminated plates having midplane symmetry is maximized for a given total thickness. The ply angle in discrete form is considered as design variables with constant ply thickness. Buckling analysis is carried out using the finite element method for uniaxial as well as biaxial loadings. It is observed that for any given ply thickness, buckling load carrying capacity can be improved by optimizing ply angle stacking sequence. The optimum results obtained using finite elements analysis for uniaxial load cases are verified by experimental results and the FEA model is validated. The validated FEA model is then utilized for Bi-axial load conditions and maximum buckling load carrying capacities obtained for various load conditions are compared with already published results. In the current study, unconstrained optimization is carried out using genetic algorithm available in Hyperstudy. It is observed that the removal of constraint like ...

Multi-objective optimization of composite plates using lamination parameters

Materials & Design, 2019

• Multi-objective optimization of composite plates is performed using lamination parameters. • Fundamental frequency, buckling load and effective stiffness metrics are maximized. • Pareto-optimal solutions are determined considering various problem cases. • A valuable insight has been provided on conformity/conflict of multiple objectives. • Presented methodology can be utilized for the optimal design of laminated plates.

A methodology for the global optimization of laminated composite structures

A methodology aimed at the global optimization of real-world laminated composite structures is introduced. It mainly consists of a parameterization scheme on the basis of the physical composition of laminated structures and a flexible and robust optimization engine using Evolutionary Algorithms. The parameterization scheme ensures, that the optimization leads to designs that can be produced easily. The methodology is validated by optimizing the stiffness of a sailing boat within given weight and cost limits.