Numercal Studies On Centrifugal Pump Installed Compound Impeller With Inducer

In recent years, the study of multistage internal flow has become the one focus of research areas in dynamics. Especially the flow of compound impeller in the centrifugal pump at low specific speed is more complex and has more problems need urgently to resolve. In this paper, the research work on centrifugal pump installed compound impeller with inducer and carry on number analysis by means of CFD and experimental.This article first the three-dimensional model of the pump are established. Based on the N-S equation and the turbulent flow model, numerical research of interior fluid of the wheel components. The pressure distribution and velocity distribution of inducer is increscent from hub to flange and axial direction. But radial direction gradient is greater than axial direction gradient. not only circumfluence exist around the inlet of the inducer and the first stage impeller, but also the flow at long blade pressure surface and the short blade suction surface of the first stage impeller is better than the flow at the short blade pressure surface and the middle long blade suction surface of the first stage impeller. The pressure range of the front diffuser becomes small to big incarnating the effect the diffuser which can change the kinetic energy to the pressure energy. The kinetic energy and pressure of the diffuser change a little incarnate the effect of the diffuser which can be seen as the pump chamber. Hydraulic performance of secondary impeller is obvious the first stage impeller.On the basis of the inducer and the first stage impeller, through altering the circumferential angle of an Inducer and the First Stage Impeller, it indicated that circular rotation of the Inducer mainly affected the inlet of vane, but the influence is very small in outlet. The most deviation values of the centrifugal-pump's rate are no more than 0. 6% and the most deviation of delivery lift don't exceed 0.09% after the cycle to angle increases or decreases 20 degree. It is indicate that influence of circumferential angle to centrifugal pump is relatively small.Finally, though the data that numerical simulation gives predicts performance curve of the pump, and contract with the performance curve that test received, analyze the error and the reason that error come into being, combine with the reference literature and revise the error, find that numerical simulation can fairly precise predict the pump performance near the place of design work conditions, prove that number analysis is reliable on the level. In accordance with the result of calculation about short-blade of different offset position on the basis of the ratio from the flow appearance in flow zone and the estimated performance curve, prove that short-blade. And contrast the whole efficiency and the head of pump which has inducer or has no inducer, it show that having inducer can obviously improve the efficiency and the head of the pump on small current capacity operating condition. But reverse at great current capacity operating mode.