轮盘最小重量设计

文中提出用一种纵向搜索——横向移动的直接优化方法来进行盘的最小重量设计。首先得出由一系列的局部最优点组成的可行域的应力约束边界,再经总体选优后,得出一个在旋转离心力、叶片拉力和非均匀温度场作用下满足强度要求的重量最小的盘。 应力分析用有限元素法。由于采用一种过渡等参元,使网格划分变得很方便。 最后,给出由OPDISK程序设计出的优化盘的例子。结果令人满意。

MINIMUM WEIGHT DESIGN OF DISKS

Disk weight is assumed to be an objective function.Because a disk is configurated by straight lines and circular arcs,design variables constitute a point A（x1,x2）in two-dimensional space（see Fig.1）.Obviously,the longer the vertical boundary of a disk web is,the lighter its weight.According to this feature a direct search optimum method,longitudinal search-horizontal move method,is proposed for optimization of a disk with minimum weight and sufficient strength for centrifugal force,tensile stress from blades and non-uniform temperature field.While using this method,calculations need neither constraint gradient nor search direction,and the design variables are reduced to minimum.It is possible to obtain satisfactory results with less number of iteration.An example given for optimizing a disk with the computer program OPDISK has testified the advantages mentioned.The FEM for stress analysis is briefly discussed in this paper.By means of an 8-nodes transition isoparametric element,it is convenient to change meshes from coarse to fine one and divide into meshes automatically.