【作者】 赵鹏；

【导师】 武强；

【作者基本信息】 中国矿业大学（北京） ， 地质工程， 2008， 硕士

【摘要】 流线的计算与显示是流场可视化中的一项基本技术,它综合了科学计算可视化技术与有限元方法,是目前流体力学领域研究的热点之一。本文归纳了地下水流动的特点和数据特点,分析了流线可视化的研究现状,运用有限元方法,通过将CFD(Computational Fluid Dynamics)的计算网格剖分为三角形单元,并在此基础上采用基函数插值,写出二维流线的详细算法,并编程实现相关算法,取得了比较满意的结果。同时在地下水三维可视化算法中,运用基于四面体剖分拓扑结构进行快速点定位,采用自适应步长的龙格-库塔法解数值积分,直接在物理空间中进行流线的追踪,避免了物理空间和计算空间之间的转换以及由此所带来的误差,提高了流线追踪的精度和效率。重点从流线的基本定义出发,研究了二维模型算法后改进了“质点跟踪”算法。采用了三维算法中的四面体基函数插值法,将类似二维的算法引入到三维中,提出了新的三维地下水速度插值公式及相应的流线算法。更多还原

【Abstract】 Streamline construction is a technique for flow visualization, which is a hotspot of Fluid Dynamics. It is formed by the Scientific Visualization and Finite EIement Method, This paper sumed up the character of grounderwater flow and data, and summarized the current status of Visualization of streamline.By the way of Finite EIement Method, through Interpolation of basis function, a successful program was finished. In the Algorithm of 3D grounderwater Visualization, a mathd of tetrahedral basis fuction was used to find the positon quickly, which include the numerical integration of Runge-Kutta Method and adaptive step. To avoid the conversion from physicalspace to computational space, a fast point location algorithmfor constructing streamline based on the normal of tetrahedron was proposed by dividing the curvilinear grids of CFD computation into tetrahedrons and the data structure was adopted to set the topological relationship among the tetrahedrons. An adaptive step was also used for fasten the numerical integration process. The presented method was demonstrated to be able to construct streamlines in a physical space directly, with improved efficiency and precision of streamline constructing.The 2D model of streamline and the definiens of streamline is the keystone to understand the paper. At last the paper presented a new mathed of velocity interpolation by the enlightenment of streamline of 3D grounderwater Visualization.更多还原