基于混合产流与二维运动波汇流分布式水文模型

Grid-based Distributed Hydrological Model with Mixed Runoff Model and Two-Dimensional Kinematic Wave Flow Model

为了提高半湿润半干旱流域的洪水模拟与预报精度,基于GIS、RS和DEM技术,以DEM栅格为流域计算单元,构建了基于混合产流和二维栅格汇流的栅格型分布式水文模型(Grid-MK-2D模型),即混合产流模型是在蓄满产流基础上增加基于Green-Ampt下渗方法的超渗产流模型,坡面二维汇流计算采用基于栅格单元的分布式运动波模型水流演算,河道汇流应用一维运动波模型演算,运动波方程组由隐式有限差分求解。将Grid-MK-2D模型、Grid-MK-1D模型与新安江模型应用于半干旱的沁河孔家坡流域并对比分析。结果表明,两个基于DEM栅格的分布式水文模型(Grid-MK-2D、Grid-MK-1D)的模拟效果优于新安江模型,但GridMK-2D模型洪峰模拟效果更好。

In order to improve the accuracy of flood simulation and prediction in the semi-humid and semi-arid basin,based on GIS,RS and DEM technology,agrid-based distributed hydrologic model（Grid-MK-2Dmodel）coupling a mixed runoff model and two-dimensional overland flow routing model was established by taking DEM grid as basin＇s compute element.The mixed runoff model is that the infiltration-excess runoff generation based Green-Ampt infiltration method was added in the saturation-excess runoff model.Two-dimensional implicit finite difference kinematic wave flow model is introduced for overland flow routing and one-dimensional implicit finite difference kinematic wave flow model is applied for channel routing.The Grid-MK-2Dmodel,the Grid-MK-1Dmodel and the Xin＇anjiang model were employed to the semiarid Kongjiapo Basin of Qinhe River for flood simulation and results comparison.Results show that the Grid-MK-2Dmodel and the Grid-MK-1D model perform better than the Xin＇anjiang model,and the flood peak simulation accuracy of the Grid-MK-2D model is higher.