Experimental Research And Numerical Simulation Analysis On The Hydraulic Characteristics Of The First Drop-sill Stilling Basin After The Sluice

The essence of underflow energy dissipation is the hydraulic jump energy dissipation. Hydraulic jump is a local hydraulic phenomena that the water leaps from the state of rapids to the state of slow flow. When the hydraulic jump occurs, the flow of the hydraulic jump can be divided into two parts:surface vortex roll and mainstream under the surface vortex roll. Surface vortex roll happens when the rapids rush into the slow flow, while the mainstream can be recognized as the flow rate becomes slower and the depth turns deeper. With strong turbulent fluctuation, the velocity gradient on the border of surface vortex roll and the mainstream is large and energy exchanges constantly. Mutation process of the hydraulic jump, flow internally generated intense friction, mixing role,consume large amounts of kinetic energy.Down the ridge stilling basin was formed in the stilling basin at the entrance down a certain depth of excavation down. Into the pool water in the pool first was jet-state into the pool, water tongue below a certain range of the formation of the reverse rotation roller,, water tongue below a certain range, the formation of "water cushion" there is a certain thickness of the reverse rotation roller,between the mainstream and the backplane.Thereby reducing the index of the hydraulics.The contents of this paper studies the contents are as follows:Firstly,this paper to the energy dissipation and scour protection issues Shahe Reservoir sluice as the research object. Geometry for the overall hydraulic model1:20scale model test measured under different conditions in the laboratory, the down stilling basin flow velocity, bottom pressure.Secondly,through model test and adjustment, optimization of energy dissipation in the down Hom plunge pool energy dissipation layout. For the sluice of the energy dissipation and the red solution to the problem put forward an alternative ideal energy dissipation layout.Finally,According to experimental observation difficult to obtain detailed the hydraulic parameters,the RNG k-ε turbulence model combined with the free surface of the VOF method to track down the ridge stilling the internal flow field numerical simulation to obtain the shape of the flow velocity distribution and pressure field distribution. Comparison of three different programs plunge pool velocity, pressure distribution on the hydraulic parameters recommend the design of energy dissipation effect of the rational and scientific, but also by the numerical simulation of in-depth study of the hydraulic characteristics down the ridge stilling basin.