Numerical Simulation Study On Improvement Project In The Lower Reaches Of The Yellow River

Based on the discuss of the rivered scouring and depositing general situation and the river technique phylogeny of Yellow River lower reaches,this paper emphasizely discussed the key problem of how to control the lower reaches rivered raising speed of the Yellow River,moreover,four relatively projects was voted in several relatively notability river management opinions of currently.The mostly work of this paper was using mathematics model to simulate and compare the four projects with the purpose of improving the Yellow River lower reaches in future,the contribution of this paper was adding the calculated function of bayou prolongation.This dissertation includes 6 chapters.Chapter 1 is general presentation,based on the analyzation of the importance and the complexity of the Yellow River lower reaches improvment,the research purpose and signification of this paper was expatiated,otherwise,the general sitiuation of Yellow River lower reaches riverbed was analyzed,in the end,the mostly work of the paper was introduced.Chapter 2 introduced and discussed the river technique phylogeny of Yellow River lower reaches,otherwise,the extruded problem of Yellow River lower reaches recently was analyzed,whereas the raising riverbed of Yellow River lower reaches and the badness change direction of water and sediment condition in future,considering the control of the riverbed celerity raising was one of the most important tasks of Yellow River lower reaches improvment.In this paper,three improvement projects with the most representation was selected in former many improvment projects,otherwise,the effect of the projects were compared with the tool of mathematics model. At the some time,considering that the long time forecast of Yellow River lower reaches riverbed is incrediable if the inflection of bayou extending was not reflected,but the scouring and depositing calculation of Yellow River was always localizated in a certain reach,the inflection of layou extending to Yellow River lower reaches was not reflected,so this model was added the calculated function of layou prolongation in the scouring and depositing change simulation of the Yellow River lower reaches.the infection of the layou prolongation can feedback the whole calculated area directly,and change the status that the lower reaches boundary condition must gave firstly. Choosing observed data of Diao Kou River to test the layou extending function of the model,the tested result accorded the observed data well,this indicated that the model can be used in layou prolongation calculation.Chapter 3 introduced the general situation of mathematics model in this projectcalculation firstly,this mathematics model adopted one-dimension unsteady unsaturation sediment model,considering the lower reaches riverbed of Yellow river was wide and fleet,the change of the water-sediment condition and the riverbed scouring-depositing is great in landscape orientation,because complex cross section method was adopted,the mathematics model is in close of two dimension. Then some related parameter management of the model was introduced,in the end,the observed data was used to test the mathematics model,the tested result accorded the observed data well,the result fill the precision request ,this incated that this model can be used in the riverbed scouring and depositing calculation of Yellow River lower reaches,and the calculated result is crediable.Chapter 4 chose four relatively projects,including originality project,narrow river projects,minus sediment project,water project,the three behind projects were father projects,moreover,the calculated boundary condition of each project was introduced,then mathmatics model was used to forecast calculate each project,base on comparing and analyzing the calculated result,the infection of each project on the lower reaches of Yellow River can be received.Chapter 5 introduced the delta general situation of Yellow River layou and observed water-sediment status and the infection of layou prolongation to the lower reaches of Yellow River, base on comparing and analyzing the calculated result,the infection of each project on the layou prolongation of Yellow River can be received.Chapter 6 is the conclusion and prospect.In this chapter it sums up the whole paper and prospects further study in the future.