Method And Implementation Of Finite Element Visualization Based On Object-Oriented Programming

The finite-element method is an effective tools in analysis many structural problems. In the course of the analysis, a mass of data is generated. How to analysis and understand the data so that it can extract the key information for engineering design, such as the stress distribution and the high stressed zone situation, is the main question in the FEM calculation. The visualization is a widely accepted post-processing. And the FEM program is a bridge between the FEM theory and the FEM computation. As the codes become more and more, the defects of traditional program languages that they have low reusability and maintainability are exposed. The OOP that appears in later 1980s can solve the problem well and have been applied widely in the field of structural analysis. To plot the colored patterns on arbitrary cut plane, the FEM visualize method and the tool of VC++6.0 is used in a subsistent frame. The study in this thesis is focused on the following aspects: 1. The OpenGL function library in VC++6.0 and the classification and function of function are introduced. In order to introduce the method of calling OpenGL in an OOP program, a simple program is presented. 2. By scanned the element pixels in some order with a series of level line whose space is given, computed the data of points in the scan line with interpolation method, established the corresponding relationship between function values and color values, set the point color in response to the point data and plotted the point according to the point coordinate with the OpenGL in the VC++6.0, the colored patterns are appeared. According to the scanning line method, the colored stress and strain patterns on arbitrary cut plain are achieved, including the tetrahedron element, the hexahedron element and the heptahedron element. Especially, the scanning line algorithm code and the flowchart program for eight nodes hexahedron element are specified. 3. The colored patterns of data on arbitrary cut body of 3D solid mesh is achieved. Especially, in the course of programming, the boundary area judgement program is developed,which accelerates the drawing procedure. 4. The validity of the colored patterns algorithm which presented in this paper is tested by two examples that are presented in this thesis with elementary discussion and evaluation. The software given in this thesis is compatible. The basis, which adapt to adding element and extending system function later, is established.