Comparative Study of Flood Simulation Methods at Small Watershed

小流域洪水陡涨陡落，又因缺乏长系列的实测水文资料，其洪水预报方案编制困难。针对该问题，以北方半湿润半干旱地区的冰峪沟小流域为例，在分析该流域气候、洪水特点以及资料获取情况的基础上，结合国内常用洪水预报模型的适用情况，选取大伙房模型和HEC-HMS模型开展冰峪沟小流域的洪水模拟研究。模拟结果表明：当前期土壤较干旱、降雨强度较大时，易于发生超渗产流，大伙房模型和HEC-HMS模型模拟产汇流的效果都较好，均可用于指导小流域进行洪水预报预警。但相比而言，大伙房模型模拟产汇流的平均误差较小，对于具有长系列实测水文数据的半干旱半湿润地区小流域，可优先选择大伙房模型进行洪水预报。而HEC-HMS模型在实测水文资料较缺乏的小流域更具有推广价值。 Due to the fact that the floods in small basins often rise and drop steeply and there is lack of long series of hydrological data, it’s difficult to establish the flood forecasting scheme. In terms of the issue, Bingyugou watershed in semi-arid or semi-humid areas is chosen as the study case. On the basis of analyzing its climate, flood characteristics and data acquisition situation, DHF and HEC-HMS models are selected to simulate flood hydrograph. The simulation results suggest that two models perform well and can be ap-plied to guide flood forecast and early warning in small basins in the case of dry antecedent soil and large rainfall intensity, infiltration-excess runoff occurred easily. The mean error of DHF model is smaller than that of HEC-HMS model. For the small watershed in semi-arid or semi-humid regions with long series of data, the DHF model is the first choice for flood forecasting. The HEC-HMS model is of great promotive value in the basins with missing data.