Research On Numerical Simulation And Model Test Of Hydraulic Characteristics For The Gate Station Project Of Shuangbaidu

The gate station project of Shuangbaidu is located in the estuary where the Biandan River goes into the Yangtze River in Maanshan city,Anhui Province.It has the functions of pumping and self-draining,and it adopts the layout of the asymmetrical gate station with the layered facade.The flow pattern of the engineering's forebay is complicated.The efficiency of the pump and the capacity of the self-draining can be reduced easily.Sedimentations can also be formed easily.In this paper,the numerical simulation and the model test are used to analyze and study the hydraulic characteristics of the gate station project,and the optimization scheme is put forward.The main research contents of this paper are as follows:(1)The numerical simulation of the original design scheme is carried out by using the computational fluid dynamics(CFD)software which is based on the N-S equation and the standard k-? turbulence model.The numerical results show that there are problems of oblique flows and sedimentations in the forebay under the multiple operating conditions,and the velocity distribution is non-uniform in the inlet conduit.Therefore,the original design scheme is inadequate,it's necessary to improve and optimize it.(2)For the existing problems of the original design scheme,the diversion pier is used to improve and optimize it.The numerical simulation on four lengths of the diversion pier is carried out.They are 20m,25m,30m and 35m.The length of the diversion pier is optimized by using the size of the vortex area which presses the main flow as the control condition,and the reasonable length range is obtained.The results show that the diversion pier which is within a reasonable length range can improve the flow pattern of the forebay and the velocity distribution of the inlet conduit,it can also enhance sediment-carrying capacity of the flow and meet the demand of adjusting the flow pattern.(3)According to the hydraulic model test procedure,the scale of the model is imitated with 1:25 by the gravity similarity principle.The model is maked with transparent organic glass plates and PVC gray boards by the roughness similarity criteria.The normal model is used to study the flow pattern of the forebay under the typical operating conditions in the original design scheme.Besides,the pictures of the flow pattern and velocity distribution are drawn.The results show that there are problems of oblique flows and sedimentations in the forebay under the multiple operating conditions.They are consistent with the results of numerical simulation.(4)Two lengths of the diversion pier are selected as typical representatives.They are 20m and 28m.And the reasonable length range of the diversion pier which is numerically simulated is verified by the model test.Compared with the original design scheme,the results show that the flow pattern of the forebay is obviously improved and the water-carrying capacity is obviously enhanced after adopting the diversion pier which is within the reasonable length range.It is reliable that the reasonable length range of the diversion pier is between 25m and 30m.(5)The method of the model test is used to study the capacity of energy dissipation and erosion-control in the downstream of the project,and the water surface profile of the downstream is drawn.According to the streamflow regime,it is concluded that the the arrangement of energy dissipation and erosion-control is basically reasonable in the downstream.The final results of numerical simulation and model test on hydraulic characteristics for the gate station project of Shuangbaidu are consistent in this paper.The results of numerical simulation effectively guided the research on the model test.They also saved the investment of the model test and increased the efficiency of the research.At the same time,the model test verified the accuracy of numerical simulation.The study methods and achievements of this paper can provide improved measures and suggestions for the design and operational management of the gate station project,which are of great significance to ensure the project operating safely,effectively and stably.Moreover,it can also provide some referent values for the design,the operating management and the research of the similar gate station project.