Generation Of Unstructured Grid And Its Use In The Calculation Of Electrical Field

The Finite Element Method (FEM) has been widely used in many research fields as a strong tool of analyzing projects. For the field of electrical engineering, FEM is also a very important numerical method, which is used in the quantitative analysis of the engineering problems, such as electro-magnetic fields and electromagnetic waves. And it is the basis of many useful and advanced software packages. Presently, the finite element analysis has been an important part of the Computer-Aided Design (CAD).The key techniques are the creation of models and the datum input, which restrict the development of FEM. And the kernel of them is the meshing of the solved regions. The progress of dividing regions is the process of creating meshes. Automatic mesh generation can save time, reduce error, enhance efficiency, and improve the computation reliability. So it is very importance to search for high speed, efficient and automatic mesh generation methods. Unstructured grids means the random of the cells and nodes, they are very random grids. Unstructured grids are greatly suitable for electric field calculation for they are suitable for carving up of grids in complex area especially and can be encrupted and sparsitied conveniently.The thesis carried through study on triangle grid mesh in two-dimensional region .On the basis of modern grid procreant technology, Delaunay triangle method and the Advancing front method are analysed separately which are in prevail in modern grid mesh technology and particular investigation and explaination are given to their concretely realizing course. They have been programmed in Fortran. The programme implement of optimization methods of grid, encrypt methods of grid, automatism giving points strategies and adding authority function method are studied in details. The analysis and comparison between Delaunay triangle method and the Advancing front method are also given in the paper.The programme of unstructured grid generation, which has been developed in Fortran, was developed on the basis of the theories mentioned as above. Two-dimensional finite elementmesh generation is performed automatically from the objects entered using above programme workouted in the thesis, and regarded as the process of finite element analysis and computation.Based on above two kinds of unstructured grids as preceding disposal data of FEM, the electrical field of high voltage breakers has been calculated using FEM. The mesh and potential curves have been illustrated in AutoCAD by using AutoLISP.