The Research Of The Hydraulic Characteristic About Surface Flow Of The Open-channel Junction Controlled By Engineering

Open-channel junction flow often occurs in inartificial river, urban water supply and drainage, discharge waste and other hydraulic engineering. There are series of complicated hydraulic phenomenon occur in main canal when branch join in. Especially in some pumping station engineerings, because of asymmetry of pumping station drainage, the main canal flow is more complicate. On the other hand, some Open-channel junction engineering which need navigation requirement, the security may be affected by transverse momentum, water separating and reflux which is caused by water junction.This article is based on research of the surface flow of open-channel junction, and study the affect factor and change law of the surface flow of open-channel junction from dimensional analysis, hydraulic model test and numerical simulation. The main contents as follows:(1)This article make a summary of Open-channel junction, and unit the researches of open-channel junction in the past, and put forward we can solve the problem of navigation security by study the surface flow of open-channel junction.(2)By dimensional analysis, it is put forward that the change law of the surface flow of open-channel junction can be study by Froude number of main canal(Fr_u), Froude number of branch(Frb), equivalent depth of water(Y_u~* ),equivalent width of bottom of main canal (W_b~* )and equivalent radius of the junction(R ).(3)Hydraulic model test is built for study the surface flow and change law of open-channel junction in case of series of velocity distributing of water.(4)Compare engineering project with numerical simulation, the feasibility of rigid-lid assumption which is used for dispose free surface of water is validated. By compare with the numerical simulation with different turbulent model and dispersed format, the numerical simulation with standard k-εturbulent model and second order upwind dispersed format can treat the project of open-channel junction exactly.(5)This paper study surface flow and change law of open-channel junction by change the non-dimensional parameter with numerical simulation. The results indicated that transverse flow on the surface of main canal is deeply affected by the flow from main canal and branch, depth of water and radius of the junction, and the factor of width of bottom of main canal is quite the contrary.