Numerical Study of Outlet Blade Angle Effect on Impeller Characteristics of Double Entry Centrifugal Pump

The characteristics of pump performance are depended strongly on the impeller geometry. Changes in some impeller geometric parameter can improve pump performance. It is well known that outlet blade angle is one of those parameters, which has significant effect on the impeller work characteristics. This work is connected with the effect of blade outlet angle changes on the performance of double entry centrifugal pump impeller. This process is investigated via Ansys computational fluid dynamics (CFD) software. CFD method can predict well the complex internal flows in centrifugal impellers. The present paper describes the simulation of four impeller working process. The outlet blade angle was changed from 26° to 32° while all other geometrical impeller parameters were kept constant. The head-flow rate, hydraulic efficiency-flow rate and shaft power-flow rate curves are compared and discussed for each impeller. The obtained results show that even insignificant changes of the blade outlet angle effect on the impeller performance.