Parametric Design Of Axial Flow Pump And Numerical Simulation

The axial flow pump is suitable for use in low lift and large flux. With simplestructure and easy to use, the axial flow pump is widely used in the industrial andagricultural departments. Especially, the South to North Water Transfer Project and otherlarge water conservancy projects require a lot of axial flow pumps with high performance.It is because of this wide range of axial-flow pump that improving the design level hassignificant social and economic benefit. This paper aims at the optimization design ofaxial-flow pump and discussing several structure parameters on the performance ofaxial-flow pump.Based on parametric concept, the axial flow pump was designed by theoreticalcalculation combined with numerical simulation in this paper. First of all, the parametersof the axial flow pump were calculated and the numerical relationship among them wasestablished with the lifting design method in the EXCEL software. Then, Script files byMATLAB programming were generated to automatically read the structure parameters inthe EXCEL table and to rapidly generate the geometry of axial-flow pump. Based onk-epsilon/RNG turbulence model and the SIMPLE algorithm, using structural grid, theinternal3-D flow was simulated by CFD software STAR-CD. The direction of structureoptimization for axial flow pump was on the basis of CFD analysis results includingprediction for lift and efficiency as well as analysis of velocity distribution and pressuredistribution. The MATLAB program was launched again after the related parameters inthe EXCEL table were modified, then the new structure was generated and so was thesimulation.The value of blade tip clearance, hub-tip ratio and cascade density of the designedpump was verified with CFD analysis. Tip clearance increase reduced the head andefficiency of the axial-flow pump. The axial flow pump with hub-tip ratio0.47has higherefficiency. As the blades overlap coefficient grew, the axial-flow pump lift slightlyincreased. The blade with backward bending angle12°has better vibration characterthan the straight one.