基于DEM的入库洪水预报模型研究及系统开发

基于数字高程模型,考虑流域空间的变异性,建立数字高程流域水系模型,在此基础上对流域空间进行离散化,划分出产汇流计算子单元并计算各子单元面积权重。将构建好的数字高程流域水系模型与集总式流域水文模型-新安江模型相耦合,建立了基于数字高程模型的数字水文模型。采用客户服务器方式将该理论模型实现为水文预报计算机软件系统,并将该系统应用于全球能量与水循环亚洲季风试验强化观测区-淮河史灌河流域,对流域内梅山水库与鲇鱼山水库进行入库洪水预报实例研究。结果表明:构建的数字水文模型可以很好地模拟水库入库洪水过程,满足实时洪水预报精度的要求。这对充分利用现有空间技术和空间数据进行降雨-径流模拟并改进水文预报方法提供了研究途径。

Forecast model of reservoir inflow based on DEM and its system development

The digital elevation drainage network model(DEDNM)was established based on the digital elevation model(DEM)considering the spatial watershed heterogeneity.The watershed was divided into a series of discrete sub-cells as the runoff generation and confluence calculation units,and the area weighting of each sub-cell was calculated.The digital hydrological model(DHM)was constituted by coupling the DEDNM with Xin’anjiang model,a lumped hydrological model.The integrated flood forecast system was based on a client/server(C/S)mode.The flood forecast system was applied in two reservoirs,Meishan Reservoir and Nianyushan Reservoir which belong to the Shiguan River watershed — the intensified observation field of GEWEX Asian Monsoon Experiment(GAME)project.The results show that the established forecast system not only performs well in simulating flood process of reservoir inflow,but also satisfies the precision requirements of the real-time flood forecast.It provides approaches to make full use of available spatial technologies and data for rainfall-runoff modeling and technical improvement of hydrological forecast.