The Research Of Flow Structure And Bed Load Transport In ShenBeiZui Bend Of Upper Yangtze River

In recent years,there has been a rapid increase in the volume of water transportation in the upper reaches of the Yangtze river,and the size of the shipping model has been increasing.so that theal authorities are eager to raise the level of the channel.in the upper reaches of the Yangtze river,the Water flow and sedimentt transport features are complicated and the waterway is more difficult to fix.Based on shenbeizui in the upper Yangtze riveras the typical representative,sharp mouth a branching channel through the prototype observation data analysis and mathematical model of two-dimensional water flow to carry out the sharp branch channel flow and sediment transport characteristics of research,and analyze its relationship with bend channel conditions and channel regulation?The main work and results of this thesis are as follows:(1)For the sharp curve of the river upstream of the Yangtze river bend the transverse slope as a whole along with the increase of flow rate gradient.Bend channel top place inside horizontal gradient change is small,curved on the top of the upper slope near the convex bank change is bigger,a curved part on the top of the downstream slope near the concave bank changes greatly.0 ° to 30 ° slope slowly decreases,and with the increase of bend degree of 30 ° to 40 ° slope increases with the increase of the bend degree,to bend the top 40 °,40 ° to 70 ° slope decreases gradually with the increase of bend degree.(2)The curve of the river channel and longitudinal slope with the increase of flow rate changes with the increase of absolute value,the channel left border(near the concave bank)overall change is bigger,in 40 ° bend(top)slope to the maximum negative slope.Channel center line of the overall change in smaller,in 60 °(with gradient to 9.5 ‰ slope)changes obviously;Channel right boundary integral(near the convex bank)change in plateau,at 60 ° slope(slope to 9.5 ‰)change is obvious.(3)The position of the hydrodynamic axis of the curved river is not very different from the increase of the flow rate,and the more the hydrodynamic axis is closer to the center line of the channel.(4)During the dry water period,the Central Line of the river channel and the Central Line of the channel is less than 57 mm,which is about 20 to 57 mm.Under theaverage flow rate of the years,the curve is less than 20 mm.In the middle water period,the bend is less than 40 mm and the mass is easy to start.In the flood period,the curve is less than 60 mm and the mass is easy to start.(5)According to god's back mouth curved section of hydrodynamic and sediment transport distribution characteristics,and put forward the right slot management ideas,and through the comprehensive improvement of the combination of regulation and dredging scheme;The research and analysis of mathematical models shows that the improvement of the control scheme is favorable for the improvement of channel condition and the stability of the channel.