Study On 3-D Turbulent Numerical Simulation And Model Experiment For Bell-like Suction Box In Large-Sized Pumping Station

Intake conduit is an important part of large pumping station, and the hydraulic characteristic of the pumping station inlet has a direct influence on the efficiency of a pump. The efficiency of the pump station can be uprated in the condition of well flow condition. Large axial-flow pumping stations because which have short conduit easily cause bad flow and lead to the efficiency of the pump unit drop and causes vibration, noise, and cavitation erosion. So, the research on the inlet flow pattern of the intake conduit, which contributes to find the flow regulations, have important mearing to optimize the design of the intake conduit with complex geometry and raise the efficiency, safety and reliability of pumping stations.In this paper, the research is divided into two major parts. One is that numerical simulation. The other is the hydraulic model test of the bell-like suction box. The research selects bell-like suction box height (or clearance from floor) as object, because it is influence to the project cost highly and has more disputes. Through the research try to discover the law of relevant factors influence the suction box performance.This paper summarize the different kinds of suction boxes and set up the 3D flow mathematic model of the bell-like suction box. A method based on 3D numerical simulation of the turbulence flow to solve Reynolds-averaged equations and the standard k-εturbulent mode is applied to analyse the flow field in the bell-like suction box. Through the numerical simulation, the factors which affects bell-like suction box flow pattern is analysed and researched, in the light of which the geometrical parameters(bell-like suction box height) of the suction box are hydraulically optimized and the reasonable criteria of the hydraulic design for the suction box are given in this paper. Besides the observation of the flow field in the bell-like suction box, two objective function is applied to analyse the results of numerical simulation. The results show that the main effect of the flow pattern is the bell-like suction box height.The result of measurement is true and reliable. It is basis and verification means of theoretical analysis and numerical simulation. But limited by some conditions, it is very difficult to launch the necessary experiment sometimes. On the foundation of the numerical simulation , this paper make an experimental research on hydraulic model of the bell-like suction box. The experiment is based upon the observation of the flow pattern and the testing of the velocity of flow. The experimental results validate the authenticity of numerical simulation. In this paper, experimental measurements and numerical simulation are combined in order to verified their results and find the flow regulations.In this paper, 4 hydraulic model test schemes and 6 numerical simulation schemes are done about the bell-like suction box. The hydraulic friction (loss of head) and some fluid state data are collected in the hydraulic experiment. In the numerical modeling, based on the Reynolds-averaged equations using the standard k-εdouble model the three dimensional turbulent flow in intake conduit is simulated. Application finite volume method discrete control equations and the SIMPLEC algorithm solve system of equations. Finally computation simulation results about the plans are obtained.The experiment and the computed results indicate that the bell-like suction box height (or clearance from floor) has a reasonable range. Results mean much to improvement of design theories and methods on suction passage and increasement of operation performance.