Experimental Study And Numerical Simulation Of Spillway With Confluence

Open-channel junction flow is a common occurrence in natural stream channel and artificial stream channel,its motion modality which is very complicated is affected by numerous of factors,and greaterly impacts on the bank protection works, and is paied close attention in practical engineering. Confluence produces many particular hydraulic characteristics,such as the ascent of water surface on the junction's upper reaches,disengagement zone and shear plane on the lower reaches. Researching and grasping the hydraulic characteristic of these special flow phenomenons generates great engineering and academic interest for bed erosion govern,urban flood control,sediment transfer and pollutant transport.The spillway in the Suyahu reservoir which is in Zhumadian city Henan province has two flood discharge gates,and the distance between them is more than 400 meters, and the two branches flow meet on the lower reaches at the location of 350 meter, then continue discharging.In this thesis,the spillway flow field of Suyahu reservoir was researched by both model experiment and numerical simulation,and the two parts of result fitted well through analyzing and comparing. The main contents as follows:(1)Model experiment of flow capacity under the conditions provided by the design unit was carried through,and the result showed the design proposal meet the challenge.(2) Model experiment of energy dissipation under the conditions provided by the design unit was carried through,and the result showed the design proposal can't meet the challenge. Updated version was proposed in this thesis.(3)Velocity distribution and flow regime measurement under the conditions provided by the design unit were carried out.(4) By using the standard k-εturbulence model, selecting VOF method to trace the free surface, the three-dimensional flow field in the spillway was calculated, and the flow regimes were accordance with the experimental result.(5) The velocity of flow calculated in the six sections in convergent area was in accord with the experimental result,which proved the correctness of numerical simulation.(6) Numerical simulation under extreme conditions was carried out, and provided a more comprehensive flow pattern of spillway flow field.