实时洪水预报中河道洪水演进关键问题研究

洪水预报是防洪减灾中重要的技术措施，1998年长江大水之后国家完善了大江大河的水雨情自动测报站网系统，从2013年开始进行全国中小河流与山洪监测及预警预报。河道洪水演进是实时洪水预报中一个关键的环节。欧美经过近一个世纪研究已经建立了守恒型非线性系列化的河道洪水演进模型，我国仍采用上个世纪七十年代发展的线性模型。根据我国不同区域河道情况，借鉴国外最新河道洪水演算预报模型的理论和方法，针对模型中线性与非线性、水量守恒与动量守恒及北方流域每年初次洪水河道水流非渐变流科学问题进行研究，建立和改进我国用于实时洪水预报中河道洪水演算系列化的模型，模型可用于大江大河干流、中小河流与山洪河道，参数既可以采用河道实测断面与水位流量资料计算，可以通过概化进行计算；研究模型与实测水文资料同化及实时校正和不确定性估计。采用河道汇流模型进行一次实时洪水预报算时间要小于10分钟，以便于用于实时洪水预警预报。

Flood forecasting is an important technical method in flood control and disaster reduction. After the flood of the Yangtze River in 1998, the station network system for automatic observing and forecasting of big rivers has been established and improved in China. The nationwide monitoring and early warning for torrential flood of small and medium rivers started at 2013. Channel flood routing is a key link in real-time flood forecasting. After nearly a century of research, a series of conservative nonlinear channel flood routing models have been established in Europe and the United States. However, the linear models developed in the 1970s are still used in China. According to the river conditions of different regions in China and the theory and method of the latest channel flood routing model in foreign countries, the scientific problems of linear and nonlinear, water conservation and momentum conservation for the model, as well as the non-gradual flow for the first flood of a year in the northern river were studied. The serialized model of channel flood routing for real-time flood forecasting was established and improved, which can be used in the main stream of big rivers, small and medium rivers and flash flood. The parameters of the model can be calculated not only by the measured section data and water level-discharge data of the river, but also by generalizations. The assimilation of model and measured hydrological data and real-time correction were studied, and the uncertainty of model was estimated. The calculation time of a real-time flood forecast using the channel routing model is less than 10 minutes in order to apply to real-time flood warning and forecasting.