Experimental Study And Numerical Simulation Of Auxiliary Energy Dissipater In Stilling Pool

Stilling basin is one of the common energy dissipation forms in underflow energy dissipation. Becauseof froude number of underflow energy dissipation is low, the ratio of dissipation generally is low, stillingbasin project quantities are large, therefore, all kinds of auxiliary energy dissipater are set up in the stillingbasin. In recent years, the hydraulic characteristics of auxiliary energy dissipater are studied by Chinesescholars, and it has obtained some research results. suspension girder is a new type auxiliary energydissipater, which has high dissipation rate, but the energy is dissipated by the hydraulic jump andsuspension girder in stilling basin, it is different from seting suspension girder in sluicing chute, suspensiongirder energy dissipater and the other auxiliary energy dissipater joint application situation are not reportedby consulting relevant literature. The article is taking Wuyi reservoir by Dina river in Xinjiang hydraulicsmodel as an example, the physical model test and numerical simulation method are applied to research onhydraulic characteristics and energy dissipation mechanism of suspension girder energy dissipater andtrapezoidal pier auxiliary energy dissipater.Through the hydraulic model test and numerical simulation of diversion tunnel and spillway tunnelstilling basin for Wuyi reservoir project, suspension girder energy dissipater parameters are ultimatelydetermined such as the optimal type, reasonable height and spacing. Taking the diversion tunnel stillingbasin for final solution with17suspension girder check flood flux (Q=773.18m3/s) as an example, a threedimensional mathematical model of suspension girder stilling basin is constructed by Computational FluidDynamics Software FLUENT. The results show that the calculation value of water surface elevation, thecalculation value of bottom pressure, mean velocity calculation value of cross section are consistent withthe model measured values, the accuracy of numerical simulation result is verified. Nine mathematicalmodel solutions are established by changing suspension girder parameters such as type, height and spacingin diversion tunnel stilling basin, the optimal shape of suspension girder energy dissipater is rectangular, thebest height of suspension girder is as high as tail-weir, the optimal spacing of suspension girder should beno less than the length of a vortex. The optimal parameters of suspension girder are successfully applied tothe stilling basin for spillway tunnel, the comprehensive type stilling basin of the joint use of suspensiongirder and trapezoidal pier is put forward for the first time, water overflow outside, and not formsubmerged hydraulic jump problem are solved under the condition of separate seting trapezoidal piers. Thedetailed flow field of the suspension girder and trapezoidal pier stilling pool is obtained, such as velocitydistribution, pressure distribution, the change of water surface line and the water depth of the typical crosssection etc. The location of the maximum pressure and negative pressure zone are determined in suspensiongirder and trapezoidal pier stilling pool, it provides a reference to auxiliary energy dissipater structuralcalculation and set the reasonable structure of aeration corrosion reduction measures, the accuracy andrationality of optimum parameters of suspension girder energy dissipater successfully are verified byspillway tunnel suspension girder and trapezoidal pier stilling basin.