Construction of a Multi-System of Structural Design of Configuration and Material Composition for Functionally Inhomogeneous Materials : Optimization Problem of Structural Element Making Use of Genetic Algorithm and Cellular Automata

本研究计画主要探讨功能非均匀材料之材料组成与结构元件配置之最佳化问题。作为分析模型，考虑了受任意非均匀供热的空心球和空心圆柱。假设非均匀材料的导热系数、弹性常数和热膨胀系数在厚度（径向）和圆周方向上任意变化。此外，空心球被视为轴对称的二维问题。另一方面，将空心圆柱体视为非对称平面应变状态。对于这些分析模型，材料组成的优化问题被认为是第一步。假设这些功能非均匀材料在超高温环境中使用，热应力松弛和耐热性都将受到影响， ...更多信息 考虑将NCE作为优化问题的目标函数。温度和相关的热弹性场的解析解的发展几乎是不可能的，因为材料的属性是任意变化的域中考虑。因此，本文采用有限元法对温度场和热弹性场进行了分析。在此基础上，利用遗传算法对材料成分进行了多目标优化，得到了空心球和空心柱等功能非均匀固体材料成分的Pareto最优解。其次，考虑了结构单元的构形优化问题。对于这样的优化问题，选择在保持强度的约束下减少重量作为目标函数。利用有限元法和软计算系统，如遗传算法和元胞自动机进行了分析。由于系统还在建设中，所以目前还不能得到数值结果，但在不久的将来会发表。少

In this research project, the optimization problems of the material composition and the configuration of structural elements for functionally inhomogeneous materials are treated. As analytical models, a hollow sphere and a hollow circular cylinder subjected to an arbitrary nonuniform heat supply are considered. It is assumed that the inhomogeneous material properties such as the thermal conductivity, elastic constants and the coefficient of thermal expansion are varied arbitrarily in both the thickness (radial) and circumferential directions. Furthermore, the hollow sphere is treated as axisymmetric two-dimensional problem. On the other side, the hollow cylinder is treated as nonsymmetrical plane strain state. For these analytical models, the optimization problems of the material composition are considered as a first step. Supposing that these functionally inhomogeneous materials are used in the super-high temperature environment, both the thermal stress relaxation and the heat resista … More nce are taken into account as objective functions for the optimization problem. The development of the analytical solution for the temperature and the associated thermoelastic fields are almost impossible because the material properties are changed arbitrarily in the domain under consideration. So that, the analyses for the temperature and the thermoelastic fields are carried out making use of the Finite Element Method. Thereafter, the multi-objective optimizations for the material composition are treated with aid of the Genetic Algorithm.The Pareto-optimal solutions of the material composition for functionally inhomogeneous solids such as a hollow sphere and a hollow cylinder are obtained. Secondary, the optimization problems for the configuration of the structural element are taken into consideration. For such optimization problems, the reduction of the weight under the restriction of the maintenance of the strength is selected as an objective function. The analyses are also developed making use of Finite Element Method and the soft-computing systems such as Genetic Algorithm and Cellular Automata. The systems are now under constructing, so that, the numerical results could not be obtained yet, but it will be published in the near future. Less