Numerical Simulation of Relationship Between Flow Pattern and Hydraulic Performance of Tubular Pump

Abstract

The bulb tubular pump had advantages of large capacity and low head. This type of pump has been widely used for water transportation project or irrigation and drainage. Nowadays China East Routine of South-to-North Water Transfers Project partly uses bulb tubular pumping station. In order to study the relationship between the flow pattern and hydraulic performance of bulb tubular pump system, the SIMPLEC algorithm, based on the RNG k-ε model with Wall-Function Law, is applied for the solution of the discretization governing equation. Using multiple reference frames, the flow detail of whole pumping system was attained. The calculation results were agreement with the test ones. The flow patterns of different operating point were analyzed. There were large eddy areas in the inlet of blades when pump systems were operated in small flowrates. The flow patterns of BEP (Best Efficiency Point) and large flowrate were good. The static pressure of suction face of leading edge was low and the static pressure of pressure face of leading edge was highest during BEP and small flowrate point. There were part low static pressure areas of leading edge of pressure surface and part high static pressure area of leading edge of suction surface during large flowrate point. The relationship between hydraulic loss of bulb of tubular pump and flowrate depended on the operating points and did not follow the quadratic law of traditional pipe. The optimal design of turbular pump should be mainly focused on the flow pattern of blades and guided vanes.