针对有限元法网格剖分和加密不方便、难以实现精确几何建模以及人工操作量大等问题,采用前期提出的独立覆盖流形法,利用其覆盖网格所具有的任意形状、任意连接和任意加密的特性,基于“凸剖分”的思路提出二维求解域的一种任意网格划分方法。在此基础上,结合前期研究的误差估计和h-p型混合自适应分析手段,尝试二维结构线弹性静力分析的自动计算,包括求解域的自动细分、多项式级数的自动升阶等过程。通过重力坝和带圆孔平板的2个算例验证了方法的可行性,其中第2个算例演示了从CAD的几何信息和计算参数输入到基于精确几何的CAE自动建模、自适应分析、成果自动输出的全过程,初步实现了CAE自动计算以及CAD与CAE的融合。
Abstract
Finite Element Method (FEM) is inconvenient in mesh division and subdivision, difficult in precise modeling of exact geometry, and costs large amount of labor operations. In view of this, we propose an approach of arbitrary mesh subdivision in the 2D solving domain based on convex decomposition idea using Manifold Method based on independent covers presented previously, in which cover meshes are of arbitrary shape, arbitrary connection and arbitrary subdivision. On this basis, with the help of error estimation and h-p version self-adaptive technology in previous studies, we attempt to implement the automatic static analysis of 2D linear-elastic structure, including the automatic subdivision of the solving domain, and the automatic elevation of polynomial orders. Two numerical examples, one of which is a gravity dam and the other is a plate with a small circular hole, are given to illustrate the validity of the present method. Especially in the latter, the whole procedure is exhibited, involving the input of geometry information and computational parameters in CAD, automatic CAE modeling with exact geometry, automatic self-adaptive analysis, as well as the automatic output of computational results. Hence, the automatic CAE computation and CAD/CAE integration are realized preliminarily.
关键词
任意形状网格 /
自动网格剖分 /
数值流形方法 /
CAD与CAE /
独立覆盖
Key words
meshes with arbitrary shape /
automatic mesh subdivision /
Numerical Manifold Method (NMM) /
CAD and CAE /
independent covers
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基金
国家自然科学基金项目(51509020);中央级公益性科研院所基本科研业务费资助项目(CKSF2016266/CL,CKSF2017052/CL)
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