Experimental Study On Navigation-power Junction’s Layout And Navigable Flow Condition Of Bending Braided River

This paper relies on the navigation lock renovation project of Lishui Qingshanpivot. Researches about navigation-power junction layout, flow characteristics of bendentrance area and the way of improving navigational conditions in the entrance area areconducted by using of hydraulic physical model, test of ship models and numericalsimulation method.The structures of pivot in bending braided river should be arrangementdistributely by research of Lishui Qingshan pivot.In this thesis, experiments ofnavigation structures layout in the left or right branches has been carried out. Andanalysis of navigation flow condition at the entrance area on upstream and downstreamand connection areas were also made. In the complicated bend entrance area,navigation condition influence by terrain and flow much，With the flow and waterdepth increase the terrain influence the navigation condition little.The navigation flowcondition on upstream and downstream of the original design on those two projectscan’t meet the specification requirements. After a preliminary optimization, thenavigation flow condition at the entrance area and connection areas still can not meetthe specification requirements.After analyzing of navigation-power junction layout, theoriginal design experiment and preliminary optimization, we found out that the schemeship lock arrangement on left branch is better than that on the right. The scheme shiplock arrangement on right branch is difficult to optimize, while the scheme ship lockarrangement on left branch can be optimized a lot. Digging flat bed, sealing the gap ofdiversion pier, extending the dividing dike and widening the channel can be used tosolving the problems near the river area at the entrance of the bumpy, sand dunes, deepgroove are strewn at random, many string ditches of complex terrain. After furtheroptimization, the navigation flow condition at the entrance area and connection areasstill can meet the specification requirements. Therefore, the arrangement of ship lockin bending braided river should be compared by optimizing.Based on the average depth FEM method, a2-D mathematical plane flow modelis established. The mathematical model agrees with physical model through theverification. And the mathematical model can be used for numerical calculation.Through the analysis of counterpart mun flow condition, backflow zone length isnegatively related to the lateral velocity, that is, the longer the backflow region thelower the lateral velocity. numerical simulation are to verify the conclusions ofPhysical model test and ship model experiment...