【作者】 郑爱勤；

【导师】 王晓明；

【作者基本信息】 西安科技大学 ， 地质工程， 2008， 硕士

【摘要】 有限差分法是一种重要的数值计算方法。该方法的应用使水文地质学计算得到了迅速发展。当前科学计算可视化是水文地质计算领域的一个重要研究方向。本文采用有限差分法,并结合可视化技术,解决水文地质计算领域的部分渗流问题,对实际工作有重要意义。实际的水文地质条件往往是比较复杂的,用解析法求解很困难,数值法为研究这类问题开辟了新的途径。它以地下水渗流理论为基础,从整个计算区域的水量平衡或质量守恒出发,建立反映整个计算区域地下水运动状况的数学模型。有限差分法是数值模拟最早采用的方法,该方法把控制方程中的导数用网格节点上的函数值的差商代替,边界条件、初始条件也相应地做类似代替,从而建立以网格节点上的值为未知数的代数方程组。其数学概念直观,表达简单,是发展比较成熟的数值方法。本文以有限差分法为基础,采用面向对象的思想,以Visual Basic6.0为开发平台,研发了关于地下水流计算的可视化系统。系统从功能上被划分为前处理、有限差分计算、后处理三大模块。前处理阶段主要完成了矩形网格剖分和不规则三角网格剖分。不规则三角网的生成采用逐点插入法。计算阶段结合实际水文地质条件,选择适当的数学模型,以有限差分法为基础,完成一维、二维承压稳定流及非稳定流计算的分析、设计和实现。后处理阶段,采用ActiveX Automation技术,在VB下与Surfer接口进行嵌入式编程,快速高效地绘制出等水头线图及立体表面图。采用OpenGL技术,绘制出非稳定流的水头变化曲线。本系统以承压含水层二维非稳定流为工程实例对系统主要功能进行测试,验证了系统在计算地下水流水头分布时具有一定的可行性。更多还原

【Abstract】 FDM(Finite Difference Method) is one of the important numeric calculation methods used in Groundwater Gynamics.The application of FDM has advanced rapidly Groundwater Gynamics. Visualization in Scientific Computing is a important studying direction in the fields of calculation in Groundwater Gynamics. The calculation of FDM need the support of Visualization in Scientific Computing, which makes for the development of Groundwater Gynamics.Actual hydrological and geological conditions are often more complex, using theanalytic method is very difficult,.numerical method to study these issues has opened up new ways. It based on groundwater percolation theory and water balance or quality conservation builds mathematical model which can reflect the whole regional groundwater movement. Being the earliest numerical simulation methods, derivatives of control equation are replaced with differece quatient of grid node function ,correspondingly, boundary and initial conditions dealed in similar, by which FDM set up equation set ,value of grid nodes unknown.With intuitive mathematical concepts, simple expression fdm is one of mature numerical methods.The paper system uses object-oriented thinking, based on the finite difference method, Visual Basic6.0 platform for the development, research and development on the basis of groundwater flow visualization system.From the functions of the system is divided into pre-processing, finite difference, post-processing module. The pre-processing stages can finish rectangular grid and the irregular triangular grid. TIN generated by the insertion point by point. In calculation stage,the system according to hydrological and geological conditions, selecting the appropriate mathematical model, based on the finite difference method, can finish one-dimensional, two-dimensional pressure steady flow and non-steady flow of the analysis, design and implementation.In post-processing phase, the system ,using ActiveX Automation technology, embedded Surfer in VB programming quickly ,efficiently plot coutour map. The system using OpenGL draw a non-steady flow curve.The system selects confined aquifer two-dimensional non-steady flow as engineering examples to test main functions,which is feasible for calculating the distribution of water head.更多还原