Reservoir Sediment Transport Processes

Xinjiang Mengjin Reservoir is a medium-sized reservoir.As a result of years of sedimentation,the water storage capacity of the reservoir has been decreasing year by year.Different solutions are put forward for the deposition treatment of the reservoir.One solution is to use the sludge to build island in the reservoir.Compared with other solutions,the scheme can save economic costs and may cause other long-term economic benefits.But the program has not yet been studied in substance.This paper selects the Delft3D-FLOW model,establishing a two-dimensional mode of Mengjin Reservoir,and calculating the erosion and sedimentation.It simulates heaped island effect by using the mathematical model based on the two-dimensional shallow water equation,in order to analyze the water dynamic characteristics change of reservoir before and after the construction of heaped island,and to reveal the law of reservoir water dynamic environment influenced by parameters such as position of heaped island.Through the simulation of the corresponding change law of water and sediment after piling island,and the law of reservoir water dynamic environment influenced by parameters such as position of heaped island,we will gain the consequences of effect of scouring and silting in the reservoir area which is related with flood and parameters of position.By comparing the reservoir landform evolution between before and after the construction of island,analyzing the overall impact of island,it provide reference to engineering application of the reservoir sediment solutions.Using Delft to simulate the Mengjin reservoir,variation of water and sediment in the extreme flood period can be calculated reliably.During the flood period of 1996,the two days of the initial stage is the key period of the topographic evolution in the reservoir.Under the influence of island situation,the characteristics of water and sediment become more complex.The island has great influence in the local area.Different locations of island have different impact on the operation of the reservoir.The erosion and deposition of the water and sediment present a certain degree of difference.In the main alluvial channel,the island has great influence on the topography and erosion of the reservoir area.