MATHEMATICAL MODELLING OF DEGRADATION AND FLUVIAL PROCESS DOWNSTREAM RESERVOIRS

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＡｆｔｅｒｔｈｅｃｏｎｓｔｒｕｃｔｉｏｎｏｆａｌａｒｇｅｈｙｄｒｏ ｐｒｏｊｅｃｔ ,ｔｈｅｌｏｎｇｄｉｓｔａｎｃｅｅｒｏｓｉｏｎａｎｄｉｔｓｅｆｆｅｃｔｏｎｔｈｅｆｌｕｖｉａｌｐｒｏｃｅｓｓｄｏｗｎｓｔｒｅａｍｔｈｅｄａｍｉｓｎｏｔａｌｗａｙｓａｄｖａｎｔａ ｇｅｏｕｓｔｏｆｌｏｏｄｃｏｎｔｒｏｌａｎｄｎａｖｉｇａｔｉｏｎ .Ｉｔｍａｙｃａｕｓｅａｓｅｒｉｅｓｏｆｐｒｏｂｌｅｍｓ ,ｓｏａｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｓｈｏｕｌｄｂｅｅｓｔａｂｌｉｓｈｅｄｔｏｆｏｒｅ…

MATHEMATICAL MODELLING OF DEGRADATION AND FLUVIAL PROCESS DOWNSTREAM RESERVOIRS

To research into the problem of degradation and fluvial process downstream reservoirs and its influence on flood control and navigation, a 1-D mathematical model of degradation and fluvial process downstream the reservoir was established in this paper. The non-equilibrium transport of non-uniform suspended load, the non-uniform bedload transport and bed material sorting were considered in the model. Some techniques were suggested for some problems in calculation, such as the effective suspended load carrying capacity of the different reaches of bed materials, the coefficient of suspended load carrying capacity, the recovering coefficient of carrying capacity, the mixed layer thickness, the bedload transport width, bifurcation and confluence of main and branch channel, and the distribution of deposition and erosion along the cross section, etc. The model was tested by the data of degradation downstream the Danjiangkou reservoir on the Hanjiang River and the data of degradation downstream the Gezhouba Project on the Yangtze River.