Optimization of thin-walled structures like an aircraft wing, aircraft fuselage or submarine hull often involves dividing the shell surface into numerous localized panels, each characterized by its own set of design variables. The process of extracting information about a localized panel (nodal coordinates, mesh connectivity) from a finite element model, input file is usually a problem-specific task. In this work, a generalized process to extract localized panels from the two-dimensional (2D) mesh is discussed. The process employs set operations on elemental connectivity information and is independent of nodal coordinates. Thus, it is capable of extracting panel of any shape given the boundary and thus can be used during optimization of a wide range of structures. A method to create stiffeners on the resulting local panels is also presented, and the effect of stiffener element size on buckling is studied. The local panel extraction process is demonstrated by integrating it into a distributed MDO framework for optimization of an aircraft wing having curvilinear spars and ribs (SpaRibs). A range of examples is included wherein the process is used to create panels on the wing-skin, bounded by adjacent SpaRibs.
翻译:机翼、飞机机身或海底船体等薄墙结构的最佳化往往涉及将空壳表面分成许多局部面板,每个面板都有自己的设计变量。从一个有限元素模型中提取关于一个局部面板(节点坐标、网格连接)的信息的过程,输入文件通常是一项针对具体问题的任务。在这项工作中,讨论了从二维(2D)网目中提取局部面板的普遍过程。这一过程在元素连接信息上采用固定操作,并且独立于节点坐标。因此,它可以提取任何形状的板块,从而可以在优化各种结构时使用。还介绍了在由此产生的本地面板上制造硬度板的方法,并研究了硬度元素大小对振动的影响。当地面板的提取过程通过将其整合成一个分布式的 MDO 框架来优化具有曲线式喷雾器和肋骨(SpaRibs)的飞机翼翼。一系列例子包括了在相邻SpaRibs的侧翼上创建面板板块的过程。