Based On The Step Neutral File Finite Element Modeling Techniques

In this paper, the technique of automatic finite element mesh generation is studied based on STEP neutral files. The boundary information of a 3-D solid is extracted from the STEP neutral file according to the semantic model of STEP/AP203 schema. The data are thus transfered from a CAD system to a CAE system. The finite element meshes are generated automatically using the Delaunay method. In chapter 1, the present development on the CAE technology is reviewed. Then, the purpose and the main line of the technique of the research is discussed. In chapter 2, the author introduces the current status and the development of the STEP standard. The main content of the standard is also listed .The EXPRESS language is detailed in this chapter with EXPRESS-G figures. The data types in STEP are also stated. At the end of chapter 2, the structure and the format of the STEP neutral file are studied. In chapter 3, the research work on the technique of automatic modeling of FEM is brought forward based on STEP neutral files. The data exchange realization between different systems is expatiated. Three modules were designed for the mesh generation system based on STEP neutral files. In chapter 4, the technique of the realization process is explained, which includes core data of the program( the data structure storing the geometry information) and the four modules of the program: the STEP neutral file access module, module of converting EXPRESS into C++, the mesh generation of FEM module, and the graphics display module. In chapter 5, the OpenGL graphics library used for the display module,which is independent of operating system. The programming method under MFC of VC++6.O is explained. In chapter 6, two examples were given. In chapter 7, conclusions and some research directions of the future are summarized.