黄河下游典型滩区“92·8”洪水分区滞洪沉沙数值模拟研究

Study on Numerical Simulation of Flood Retarding and Sand Silting of "92·8" Flood District in Flood Plain of the Lower Yellow River

采用平面二维水沙数学模型,依据"92·8"典型洪水情况,对黄河下游夹河滩至高村河段进行了无生产堤条件下的自然漫滩、现状生产堤条件下漫滩及典型滩区分洪淤滩,3种工况条件下的河道冲淤、洪水演进及滩区淹没的数值模拟.模拟成果分析表明,对黄河下游蓄滞洪区进行滞洪沉沙,有效增大了分洪区的削峰滞洪作用,保证和扩大了滩槽泥沙横向交换,维持了河槽活力,一定程度上可以缓解黄河下游"二级悬河"的状况.

The 2-D water and sediment mathematical model which reflects flood retarding and sand silting of flood plain in the Lower Yellow River has been set up in this paper. Through carrying on 2-D water and sediment numerical simulation of the ＂92 · 8＂ typical flood, the authors studied influence of zoning flood retarding and sand silting on flood travel. The simulating results in different conditions show that, adopting the zoning flood retarding and sand silting in the Lower Yellow River effectively worked on retarding flood and sharpening peaks in the flood retarding basin, guaranteed and expanded transverse exchange of water and sediment in the floodplain and channel, and maintained the vigor of the river channel. This can relieve ＂secondary suspended river＂ states in the Lower Yellow River to a certain extent.