Bi-directional evolutionary algorithm for volume constrained topology optimization of axisymmetric solids

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2015
Tikenoğulları, Oğuz Ziya
In this thesis, topology optimization of axisymmetric solids is studied. Analysis of the axisymmetric problem is performed by coding an axisymmetric finite element formulation in association with the optimization code which is based on Bi-Directional Evolutionary Optimization (BESO) method. The optimization method used in this study includes recent improvements to the evolutionary optimization algorithms. These are bi-directional evolution, sensitivity number filtering and sensitivity-time averaging. In the optimization process, mean compliance of the overall structure is minimized while gradually removing material in order to reach volume constraint. Removal of the material is decided according to the strain energy stored within the volume of the finite element. In this study, hard-kill method is used for the element removal. Therefore removed material has no contribution to the stiffness of the structure. In the analysis of the structure, iso-parametric axisymmetric finite element formulation is used.Both the analysis and optimization codes are run in a successive manner. Sample problems are chosen from the literature and solved with the present optimization method. Results are compared and performance of the method is discussed.

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Citation Formats
O. Z. Tikenoğulları, “Bi-directional evolutionary algorithm for volume constrained topology optimization of axisymmetric solids,” M.S. - Master of Science, Middle East Technical University, 2015.