Study On The Influence Of Combination Of Picking And Transition Steps On Integrated Energy Dissipator

In order to solve the problem that there is a contradiction between the high energy dissipation rate and the cavitation damage when the integrated energy dissipation facility is operated under large single-wide flow,this paper is based on the model of the 1:60 model based on the Ahai power station.In the hydraulic model test,a total of twelve combined aeration facilities were combined with three angles of aerated picks and four types of ladders,and the effects of the twelve combined aeration facilities on the hydraulic characteristics of the integrated energy dissipator were analyzed.To provide a theoretical basis for the integrated energy dissipator to be applied to higher heads and larger single-width flow projects.The main conclusions of the study are as follows:(1)When only the transitional step body type is added,it is found that the influence of the first-level large step on the aeration of the integrated energy dissipator is more prominent;when the combined facilities of the aerated picking and transition ladder are added,it is found that 11.3°,1m+with one The combination of the large step transition steps is the optimal combined aeration facility;(2)The law of time-averaged pressure and flow rate is basically similar.There are two peaks in the maximum pressure-average pressure,one is the maximum impact pressure of the anti-arc section,and the other is the maximum hydrostatic pressure of the stilling pool section;In the gas installation,when the angle of the picking is certain,the first step is the transitional step of the large step,and the maximum energy consumption is the highest,and the maximum value is about 90%;(3)The maximum negative pressure under the picking ridge+uniform step type appears at the first step facade lobe;and the position of the maximum negative pressure of the combination of the picking ridge+the new transition step is shifted down,both appearing in The second step of the elevation of the facade;the maximum negative pressure of all test schemes does not exceed the maximum negative pressure allowed by the specification;and the maximum negative pressure of the twelve test schemes appears at 11.3°+the first order is In the large step transition step body type scheme,the maximum negative pressure value is-5.46 kPa;(4)When the transition step is added,the maximum aeration concentration is only 61.6%,and the maximum length of the aeration cavity is 13.88m.After the combined aeration facility is added,the first and second steps are large steps or no steps.In the stepped type scheme,the maximum concentration of aeration is less than 50%,and the maximum concentration of aeration of the first step is a step ladder with a large step exceeding 60%,and the length of the cavity increases with the angle of the pick.When the angle of the picking is fixed,it is found that the first step is the step ladder of the large step.The cavity length value is the largest,and the aerated gas concentration and the cavity length value are the largest at 11.3°+the first step is the large step.In the transitional ladder body type,the maximum values are 88.46%and 17.50m,respectively;(5)When the transitional ladder is added,the maximum energy dissipation rate reaches 52.70%.After the combined aeration facility is added,the maximum energy dissipation rate reaches 59.95%.In summary:that adding a combined aeration facility at the junction of the integrated energy dissipator step and the WES surface can reduce the negative pressure existing at the junction,and improve the aeration amount and energy dissipation effects of the integrated energy dissipator.Among them,the optimal combination aeration facility has a shape of 11.3°+the first step is a large step transitional step body type.