面向混合曲面模型的自动拓扑生成算法  

Automatic topology generation algorithm for hybrid surface models

作　　者：曹秉万[1,2] 陈建军[1,3] 郑耀[1,3] 黄争舸[1,3] 郑建靖[1,3] 

机构地区：[1]浙江大学工程与科学计算研究中心,浙江杭州310027 [2]浙江大学计算机科学与技术学院,浙江杭州310027 [3]浙江大学航空航天学院,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2014年第5期923-933,共11页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(11172267;10872182);国家"十一五"科技支撑计划资助项目(2009BAG12A01-C02);国家水体污染控制与治理科技重大专项(2009ZX07424-001);中央高校基本科研业务费专项资金(2012FZA4026);浙江省自然科学基金资助项目(Y1110038)

摘　　要：为兼顾连续曲面和离散曲面表征的长处,提出混合曲面模型的概念,将2类表征统一到曲面B-rep数据结构中.基于混合曲面模型实现新的连续曲面自动拓扑生成算法,可修复连续曲面模型中存在的边界曲线交缠和存在细缝等缺陷.新算法修复离散曲面,利用离散曲面和连续曲面之间的基本映射关系重建连续曲面丢失的B-rep拓扑.拓扑修复后,可复用基于有效B-Rep的曲面模型特征简化及网格生成算法.在整个算法流程中,几何计算主要定义在离散曲面上,连续模型的形状没有变化,且最终网格点都在连续模型上.结果表明,新算法能够针对包含交缠和细缝等缺陷的连续曲面模型生成拓扑正确且质量较高的曲面网格,可满足CFD等应用对高几何保真网格模型的要求.An enhanced boundary representation （B-rep） that combines the continuous and discrete surface representations was proposed to exploit the strengths of both representations, which enables a novel automatic topology repairing algorithm for continuous surfaces with small gaps and overlaps on surface bounda- ries. The proposed algorithm first repairs the discrete dual of the input continuous model, and then re- builds the lost B-rep topologies of the continuous model based on the dual relation of the discrete and continuous models. After topology repairing, the existing surface defeaturing and meshing algorithms that require a valid B-rep input are reused. In all of these steps, geometry computations mainly occur on the discrete model. More importantly, the geometry of the continuous model remains unchanged from the very beginning, and the output surface mesh is loyal to the continuous model. Therefore, this outcome is desired by the applications such as computational fluid dynamics （CFD） where a mesh model with high geometrical fidelity is preferred.

关 键 词：几何修复 特征简化 网格生成 虚拓扑 边界表征 

分 类 号：O242[理学—计算数学]