Hydraulic Model Test And Numerical Simulation Study Of Baiyang River Reservoir Spillway

The spillway is a familiar flood discharge construction in hydraulic project,but the spillway are arranged with different forms.In the practice engineering,because of the restrict of various conditions,or in order to make the best use of the terrain,or reduce the amount of work,it had to set the contraction section in the plane,This type of spillway would often produce supercritical shock wave if the flow was rapid stream,when discharge flood.Shock waves can have a serious impact on the discharge.So dissolving the effect of supercritical shock wave has an important significance for safe running of engineering.This paper studies the spillway discharge capacity,discharge flow state,velocity and pressure distribution characteristics of Baiyang river reservoir through a combination of model experiment and numerical simulation.Especially,this paper optimized the size of the contraction section after the spillway.The experimental results of the original design show that the width of the WES weir in the spillway is obviously insufficient and can not meet the requirements for the design and check of the discharge flow;the deflected flow occurs in the contraction and the maximum water depth reaches 4.5m,exceeding the height of the side wall.the water-wings of the first stage energy-dissipating section is serious,and the absolute value of the negative pressure on the surface of the vertical ladder is very high,and the step size needs to be optimized.Aiming at the problem of insufficient flow capacity and rapid shock wave in the original design scheme,a modified scheme was proposed to increase the width,reduce the shrinkage angle and set up the inverted deflector.The modified scheme was verified through experiments,and the experimental data were used to verify mathematical model and its empirical coefficient.The verified mathematical model was used to numerically simulate the flow state when the deflector body was set in the contraction section.Based on the experimental and numerical simulation results,the effect of body shape change on the shock wave was analyzed,and the optimal deflector body shape was obtained.The results showed that the width of the spillway of the Baiyang river Reservoir increased from 27 m to 32 m,the contraction segment begins with 0+017.00 and extends from 0+057.00 to the 0+065.40,and the width of chute is contracted from 33 m to 10 m.the contraction angle changed from 12.68° to 13.36°.Arranging the optimized deflector upstream of the contraction greatly improves the flow pattern of the contraction and the step section,deflected shock wave peak reduces,cross-section water depth is well-distribution,which can meet the requirement of flood discharge and run.The program provides reference and guidance for designers as a recommended solution for the spillway,and the deflector type optimization process can provide reference for similar projects.