摘要
有限元网格生成技术是工程科学与计算机科学的一个重要研究领域,随着计算机技术和信息技术的广泛应用和飞速发展,网格生成技术已成功应用于计算力学、有限元分析等工程领域,成为解决数值解析与模拟等复杂问题的强有力手段。
整体叶盘是现代航空发动机的一种新型结构部件。整体叶盘已经被列为新型航空发动机、火箭发动机的重大改进部件,为达到对其进行优化设计的目的,针对性地对其进行建模及网格自动生成的系统开发,具有十分重要的工程应用价值。
本文对基于OpenCASCADE的整体叶盘建模方法和四面体网格自动生成的相关技术进行了研究和探讨,主要内容包括:
研究了OpenCASCADE的建模模块,包括拓扑数据结构、数据类型、拓扑关系、模型显示、文件存储等。以整体叶盘为例,并结合发动机整体叶盘的结构特点,将OpenCASCADE开发平台引入到航空发动机整体叶盘的建模过程中,实现了基于OpenCASCADE发动机整体叶盘建模。
研究了限定Delaunay四面体生成的BFS方法,包括限定条件的表示方法及其规范化要求、规范化算法。介绍了BFS方法的思路、算法介绍和BFS方法的效率分析,给出了薄元问题解决方法。
在上述研究的基础上,讨论了四面体网格的质量标准,对各种四面体网格生成方法做了比较,采用C/C++结合OpenCASCADE,利用TCL/TK脚本语言开发界面,实现了基于OpenCASCADE的整体叶盘建模和限定的Delaunay四面体网格生成,并给出了实例。
Finite element method is an effective means in solving complex engineering problem.Finite element mesh generation method is a crucial step of finite element numerical simulation and it has a direct impact on the accuracy of follow-up analysis results.
Blisk has been classified as a new aviation engine and rocket engine components significant improvements to achieve optimum design of its purpose, the targeted development of blisk’s modeling and automatic mesh generation system,it would have a very important project value.
In this thesis, based on the OpenCASCADE blisk modeling methods and automatic generation of tetrahedral mesh related technologies were studied and discussed, the main contents include:
Research on OpenCASCADE modeling module,including data type,topology,model,data storage,and so on.According to the structural characteristics of blisk,completed blisk modeling based on the OpenCASCADE.
BFS(Boundary Facet Subdivide) methods in Constraint-based Delaunay tetrahedral mesh generation,including restrictive conditions and standardized requirements, standardized algorithm. Introduced the idea of BFS method, the algorithm and the efficiency analysis method.Using C++ and OpenCASCADE realized constraint delaunay tetrahedral mesh generation algorithm.
Discussed the tetrahedral mesh quality standards,using C++ binding OpenCASCAD and TCL/TK achivethe blisk modeling and constraint delaunay tetrahedral mesh generation, and gives examples.
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