水库流域雨洪耦合预报方法研究

针对许多面积小于1000 km²的小流域洪水预见期只有3 h左右,有的暴雨中心在库区的洪水甚至不足1 h,严重影响水库防洪效益发挥,迫切需要通过降雨定量预报延长预见期。为此,研究建立了定量降水预报模型,较好解决了降水信息场与水文模型时间和空间尺度上的匹配问题,缩小两者的尺度差异,使得雨洪模型更匹配;然后利用系统微分响应技术提取实测流量的信息逆向反馈降雨预报模型,修正降水预报结果,通过正向和逆向信息流构建了较为完善的耦合结构。模型在汤浦水库流域首次进行了应用检验,获得了较好的结果。

Study on the Coupling Forecasting Method of Rain and Flood in Reservoir Basin

For many small river basins with an area of less than 1000 km²,the flood foreseeing period is only about 3 hours,and if the torrential rain center is close to the dam,the foreseeing period would even be shortened to less than an hour,which seriously affects the flood control benefits of reservoirs,so it is urgent to extend the flood foreseeing period through quantitative precipitation forecasting.To this end,a quantitative precipitation forecasting model is established that can better solve the matching problem of precipitation information matrix and hydrological model on time and space scales,reduce their scale differences and make the precipitation and flood forecasting models better cooperated.Then,a system differential response technology is proposed to extract measured flow rate,which reversely feedbacks the precipitation forecast model and update the precipitation forecast results.Thus,a coupling forecasting structure of rain and flood that is capable of dealing both forward and reverse information flows is finally established.The model is applied in Tanpu Reservoir Basin for the first time and the forecasting results are satisfactory.