基于不规则三角形网格和有限体积法的物理性流域水文模型  

Physically based hydrological model using finite volume methods based on a triangulated irregular network

作　　者：王蕾[1] 田富强[2] 胡和平[2] 

机构地区：[1]中国水利水电科学研究院,北京100048 [2]清华大学水利水电工程系水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水科学进展》2010年第6期733-741,共9页Advances in Water Science

基　　金：国家自然科学基金资助项目(50779022)~~

摘　　要：传统的栅格离散方式不能很好反映流域水文过程的边界特征,且难以实现流域水文过程的多尺度模拟。采用有限体积法构建了基于不规则三角形网格的物理性水文模型,将物理性描述的偏微分方程组在控制体积内积分得到空间半离散的常微分方程组,保证数值求解中的水量平衡,并可与概念性描述部分水文过程(如截留、填洼等)的常微分方程组更好地耦合;建立了数值求解方案,采用Triangle对计算区域进行离散,并在沁河上游流域进行了验证,结果表明模型具有较高的模拟精度和良好的应用前景。The physically based hydrological models are based on the physical descriptions of water movement within the overland, river channel and soil, which makes it promising that the hydrological modeling depends less on the calibration of watershed responses while depends more on the observations and measurements of climate and landscape themselves. The spatial discretization is the very first step in the development of physically based models, and at the same time, it is also the principle way to represent the spatial heterogeneity of landscape properties such as topography, soil, vegetation, etc. The grid based method for spatial discretization is one of most commonly used ways for its simplicity. However, the method cannot represent the heterogeneity in a realistic and efficient manner, and most importantly, the gird based models may not be suitable for the modeling of multiscale hydrological processes. In this study, a physically based hydrological model is developed on a triangulated irregular network (TIN). The model partial different equations (PDEs) derived at micro-scales include the Richards equation and Saint-Venant equations. The model is resolved numerically using the finite volume method (FVM) that can integrate the PDEs over the controlling space into ordinary differential equations (ODEs). The use of FVM can ensure the balancing of water mass in the numerical solution, as well as makes it easier when coupling to other ODEs of canopy interception and ground depression. The model is tested over the upper region of the Qin river basin. The results show the reasonable modeling accuracy and efficiency.

关 键 词：不规则 三角形网格 有限体积法 物理性 流域水文模型 triangulated irregular network based finite volume methods 流域水文过程 常微分方程组 数值求解 偏微分方程组 离散方式 多尺度模拟 应用前景 水量平衡 上游流域 模拟精度 描述 控制体积 

分 类 号：P641[天文地球—地质矿产勘探] TV[天文地球—地质学]