Influence of Middle Division Pier on the Hydraulic Performance for Inlet Conduit of a Large-scale Pumping Station

The combination method of numerical calculation and model test was applied to investigate the effects of middle division pier on the hydraulic loss and flow uniformity and average flow entrance angle at the outlet conduit when the inflow direction was oblique at the elbow inlet conduit.The influence mechanism was analyzed preliminarily.The research results indicated that(1)the influence of the middle division pier on the flow pattern at the elbow inlet conduit is insignificant with an increasing of hydraulic loss of about 0.005munder the design discharge;(2)when transverse velocity exists in the forebay,the middle division pier is beneficial to improve the flow pattern at the inlet conduit;and(3)the increasing of hydraulic loss at the inlet conduit is mainly due to the increasing of flow velocity caused by the reduction of flow area.The results obtained from the numerical simulation method were consistent with those determined by the model test method.