面向错位装配体的自动曲面嵌入算法  

Automatic surface imprinting for misaligned assembly CAD models

作　　者：刘智伟[1] 杨洋[2] 陈建军[1] 郑澎[2] 夏一帆[1] LIU Zhiwei;YANG Yang;CHEN Jianjun;ZHENG Peng;XIA Yifan(School of Aeronautics and Astronautics,Zhejiang University,Hangzhou 310027,China;CAEP Software Center for High Performance Numerical Simulation,Beijing 100088,China)

机构地区：[1]浙江大学航空航天学院,杭州310027 [2]中国工程物理研究院高性能数值模拟软件中心,北京100088

出　　处：《空气动力学学报》2022年第5期166-174,共9页Acta Aerodynamica Sinica

基　　金：国家数值风洞工程(NNW);国防基础科研核科学挑战专题(TZZT2016002)。

摘　　要：分部件建模获得的装配体其部件和部件之间的共享区域在不同部件中存在多份表征,直接在该模型的原始边界表征上生成网格,重叠区域的网格在几何和拓扑上都不兼容,不能用作数值模拟分析。针对错位装配体中的重复表征问题,应用连续-离散混合曲面造型方法,提出了适用于装配体模型的自动曲面嵌入算法,该算法在离散层面上通过线段-三角形相交计算边界相交图,并通过拓扑操作移除三角形相交问题,完成离散曲面的嵌入;而后根据边界相交图及离散嵌入结果,设计相应的曲线曲面分裂合并等操作,完成连续曲面B-rep上的自动曲面嵌入。并在典型算例下用嵌入后的B-rep为输入,以其网格生成结果来验证了该自动曲面嵌入算法的有效性。In a geometry model assembled part by part, multiple surface representations exist between the common regions of neighboring parts. Generation of meshes for such a model directly would produce a nonconsistent mesh in these common regions, which is not a qualified input of conventional simulation solvers. In this paper, a novel automatic surface imprinting algorithm based on the hybrid representation of surfaces is proposed to remove these multiple representations. Here, the hybrid representation of a surface refers to a new data structure that stores both discrete and continuous representations of this surface and always maintains their mappings. The imprinting algorithm firstly solves the segment-triangle intersection in misaligned boundary regions to get the boundary intersected graph, then we apply topology operations to uniform the triangle-triangle intersections in intersected regions. Based on the boundary intersected graph and intersection-free discrete representation and the mapping between discrete and continuous representation, the curve splitting, curve merge,surface splitting, and surface merge are specifically designed to automatically accomplish the imprinting in Brep. Finally, we take the imprinted B-rep as input, a mesh generation pipeline is conducted on several numerical experiments to demonstrate the effectiveness of the new algorithm.

关 键 词：网格生成 装配体 曲面嵌入 自动化 混合曲面表征 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]