为了解决非均质材料零件设计中几何特征和材料特征的耦合问题,提出了一种基于可行方向法和遗传算法的几何和材料的并行设计方法。通过设定关键点来表示不断变化的零件几何特征,引入虚拟节点以描述其材料特征,构建非均质材料零件几何和材料并行设计的优化模型。在优化设计过程中,关键点的坐标增量采用可行方向法求解,虚拟节点的材料体积分数增量通过遗传算法获得,两种优化算法交替迭代,便得到了零件几何形状和材料分布的组合最优解。采用该方法设计了一个非均质材料的等温器具,通过有限元技术对其温度场和应力场进行模拟和分析,并利用ANSYS软件对设计结果进行验证,从而说明了该方法的有效性和实用性。
For solving the coupling of geometry with material in the design of heterogeneous objects,a concurrent design method for geometry with material based on the method of feasible direction(MFD) and genetic algorithm(GA) was proposed. The geometrical features were expressed by the coordinates of a set of key points and fictitious nodes were introduced so that material features could be denoted for the changing of modeling. A concurrent optimization model of geometry and material for the heterogeneous objects was presented. During the process of optimal design, the coordinates' increments of key points can be calculated by MFD while volume fractions' increments of ficitious nodes are obtained through GA. Thus,the optimum solution of geometric shape and material distribution can be obtained by alternatively utilizing of the two algorithms. An isothermal heat utensil made of ZrO2 and Ni is designed using this method. Finite element method(FEM) was utilized to perform the simulation and analysis of the utesil's temperature field and stress field. The optimal results are verified by ANSYS software, which show the method proposed is of good efectiveness and engineering applicability.