The Numerical Simulation Of Flow Fields In Inverted-Arch Plunge Pool And The Static Analysis Of Inverted-Arch Structure

Based on joint spillway with the surface deep hole of high arch dam in Laxiwa project and arch invert water plunge pool, the scheme of high arch dam plunge pool's flood discharge and energy dissipation and the carrying capacity of invert arch structure under different levels uplift pressure when the plunge pool are emptying have been calculated numerically and compared.(1) In the flood discharge and energy dissipation program of numerical calculation, three-dimensional integrated model of reservoir with sluice spillway and deep hole with plunge pool are established by RNGκ-εturbulent mathematical model and the free surface is handled by VOF method. Then the pressure spatial distribution in the whole process of water jets from mass ejection in the air, collision, rushing to the plunge pool and develop into the pond and the wall of plunge pool are calculated when the joint flood working condition are two deep hole, three surface hole and both of them.The features of water flow pattern, velocity field and pressure field are received. By a detailed comparing with the corresponding measured values, it is proved that both are in good agreement and the calculated results are reliable.(2) The anti-arch floor structure model are established by finite element theory. Besides, the carrying capacity of invert arch structure under different levels uplift pressure when the plunge pool are emptying are analyzed.The numerical simulation shows that:any bottom structure are not instable when arch-terminal structure are not destroyed under the similar level of uplift pressure in the engineering practice or the arch abutment without vertical displacement under the overload level of uplift pressure arch-terminal structure are not destroyed.But the concrete may be destroyed especially near the keyway contacted with the two floor plate in the later condition.With the increasing of the uplift force, the displacement of floor plate increase. The gap of floor plate are open in maximal displacement and the other sometimes are open and sometimes are close. It doesn't work to set a keyway to decrease the displacement in the floor plate and it is similar with the straight seam condition. So there is no obvious regularity between the differences in both. The stress in floor plate with keyway are more than it with straight seam under the same level of uplift pressure. The more and concentrate stress in the keyway are produced, however, this condition does not occur in the straight seam way. Both of them meet the stress requirements.Research results are available to provide references for the design and research of anti-arch plunge pool, flat-bottomed plunge pool and the stilling basin, being important theoretical and applied significance.