Hydraulic model for flood forecast of river basin with flood diversion and flood retarding ar-eas of Huaihe River

Abstract

针对淮河流域河系特点, 建立淮河具有行蓄洪区河系洪水预报模型.干流河道洪水演进采用一维水动力学模型, 钐岗分流量利用分流曲线法推求, 利用虚拟线性水库法解决大洪水时支流洪水受干流顶托作用, 临淮岗闸作为水力学模型的内边界条件进行处理, 利用分流比法概化行洪过程, 行洪区内只有蓄满时, 才会有出流, 行洪区内的洪水利用Muskin-gum法进行洪水演进;由于蓄洪区进洪与出流均有闸门控制, 因而作为水库处理, 蓄洪区内不考虑洪水演进, 只进行水量平衡以判断进洪或者出流.以淮河干流王家坝至鲁台子河系为例, 建立淮河具有行蓄洪区河系水力学模型, 并与淮河具有行蓄洪区河系水文学模型在淮河2003-2008年洪水进行对比验证检验.结果表明, 所建立的淮河具有行蓄洪区河系洪水预报水力学模型在淮河洪检验取得较好的预报效果, 也证明了所建模型的合理性。;Hydraulic model of Huaihe River with flood diversion and flood retarding areas was developed for flood forecast.The in-put flood discharge hydrograph from the main channel to the flood diversion area is estimated with the fixed split ratio of the main channel discharge.The Muskingum discharge routing method is applied in the flood diversion area,and outflow can generate only after it reaches full storage.The flood flow inside the flood retarding area is calculated as a reservoir and inflow and outflow are cal-culated based on the water balance equation.Taking complex river basin between Wangjiaba and Lutaizi stations with flood diver-sion and flood retarding areas of Huaihe River as an example,with taking the Linhuaigang Project as inside boundary in flood rou-ting,Hydraulic model of Huaihe River based on one-dimension hydraulic model was developed.In order to testify the performance and rationality of the developed model,the representative flood events from 2003 to 2008 were forecasted with the developed hy-draulic model.Results show that the developed model performs well and is reasonable.