Research And Realization Of Non-uniform FDTD Mesh Generation System In Cartesian Coordinate

With the development of electromagnetic field and high-performance computers, computational electromagnetic has been improved greatly in recent years. Among all the methods, the Finite-Difference Time-Domain (FDTD) method attracts more and more attentions and applications because of its unique features. It is a hot research topic in the electromagnetic domain that how to carry out electromagnetic simulation through computer technology and display electromagnetic variation and distribution of different medium vividly so as to divide calculation areas reasonably and generate mesh automatically, which can provide data resource and visual service for FDTD analysis in later stage. Based on computer graphics theory and OpenGL technology, electromagnetic FDTD mesh generation system and graph visualization have been deeply researched in this thesis. The main contributions are as follows:(1) In view of symmetrical curve function theory, an algorithm is introduced in details, which can generate the non-uniform mesh effectively. By using an application sample, we have proved these grids which are produced by the algorithm are not only accurate but also reasonable, and the precision of mesh computation is also enhanced.(2) Based on computer graphics theory and OpenGL technology, we not only analyze the 1D, 2D, 3D and section grids of non-uniform FDTD mesh generation system in Cartesian coordinate, but also give the algorithm steps of mesh generation and improve hidden-image mechanism of OpenGL used to realize refined hidden-image of grids graph. The visual effect of mesh graphics for FDTD emulation and simulation is enhanced greatly.(3) Based on the Microsoft Visual Basic6.0 platform, a Non-uniform FDTD Mesh Generation System in Cartesian coordinate is developed in this thesis. All functions designed by the system have been achieved including 1D, 2D, 3D FDTD grids, section grids and object geometry patterns. These graphs can be checked, adjusted and modified dynamically and visually in multi-directions and multiple perspectives. Grids partition data and grids graphics can also be saved and derived in a certain document.At present, the system has been developed successfully and has great running performance, which can satisfy the customer of FDTD in application and provide the service of electromagnetic computation and visualization for electromagnetic theories research and related circuit design. It has important practical value for research, engineering and teaching.