Topology optimization of 3D structures using improved ESO method

Abstract

In this paper, an improved ESO (Evolutionary Structural Optimization) method for the topology optimization of 3D structures is proposed. In the proposed method, the idea of BESO method and the idea of extended ESO method are combined. In this method, the design domain is divided in same eight-node brick elements (voxels), and in the optimization process, for solid element, it will be removed if the strain energy is less than the threshold value. This threshold value is obtained from the equation proposed in extended ESO. This equation consists of the mean value of sensitivity number and the average deviation of sensitivity number with a control parameter. In the proposed method, the evolutionary volume ratio (reduction ratio) is given as input data, and this control parameter is determined automatically in the program so as to satisfy the given reduction ratio approximately. Several numerical examples are shown in order to demonstrate the effectiveness of the proposed method for 3D structures.