Pumping Unit Model Experimental And Flow Channel Numerical Simulation Of Pogang Lake Eastern Pumping Station

Pogang lake eastern pumping station has two functions of flood discharge and storm drainage. The design flow of flood drainage is 68m3/s, This part is installed four sets of pumps for 2200ZLB 18-5.7 vertical half regulating axial-flow pump. The design flow of storm drainage is 30m3/s, This part is installed two sets of pumps for 2200ZLB 16.8-6.6 vertical half regulating axial-flow pump. The diameters of impeller are all 2000mm and matching electric motors for the pump are all TL1600-28/2600 vertical synchronous motors with 1600kW capacity of single machine. The pumping station uses elbow inlet passage and straight pipe outlet passage. Tianjin TJ19 hydraulic model test is selected by the design of Pogang lake eastern pumping sation. According to the hydraulic model and control the size of Pogang lake eastern pumping station selection and model test of pumping unit, hydraulic performance is researched and the safe, efficient and stable operation of the pump in the operating range of the pump station is verified. At the same time, CFD simulation is used for inlet and outlet flow passage numerical simulation of pumping station in order to verify the flow characteristics of inlet and outlet channels. The inlet flow channel is optimized in order to further improve the fow condition of inlet flow channel.In the light of TJ19 model, five blade angles are tested.They are -4 degrees,-2 degrees,0 degrees,+2 degrees and +4 degrees. The dynamic characteristics of different blade angles can be obtained by testing different blade angles. According to the experimental characteristic results, comprehensive characteristic energy curves of the model and prototype can be drew. Because cavitation allowances of different blade angle are tested,different cavitation performance results and critical changes of NHSH curves are got. The runaway speed is measured by opening the auxiliary pump at different blade angles and the runaway curve can be drew. The fluctuating pressure is measured by capacitive differential pressure transmitter. According to the experimental results, pump device efficiency indicators can reach a higher level without cavitation hazard.The runaway characteristics meet the specifications and the fluctuating pressure also in a safe range.Meanwhile, the paper uses the three-dimensional numerical simulation software FLUENT. It is used to conduct simulation analysis and calculation for the flow area ratioin of Pogang lake eastern eastern pumping station inlet and outlet conduit. The numerical calculation is mainly related to the governing equations:Instantaneous control equation of turbulence, Turbulent time average control, k equation, ε equation. The inlet and outlet channels mainly use three performance indicators:Outlet flow drift angles θ, Axial velocity distribution η, Resistance coefficient of flow passage S. The results of numerical simulation show that the flow of the elbow inlet channel is orderly and uniform without undesirable flow regimes. The straight pipe outlet flow channel meets the requirements of the hydraulic design of flow with orderly and uniform flow regimes. The inlet flow channel uses 4 optimization schemes in order to further improve the efficiency of the pump device. Further improvement of the hydraulic performance of the optimized inlet flow channel is obtained.The paper provides an important basis for the engineering construction of Pogang lake eastern pumping station by the methods of the model tests and numerical calculation combined.At the same time, this article provides a good reference for future renovation of large-sized pumping station construction.