Impact of impeller type on performance of high-speed centrifugal pumps with ultra-low specific-speed

To analyze the performance of high-speed centrifugal pumps with ultra-low specific-speed,numerical simulation of inner flow in centrifugal pump with ordinary impeller and complex impeller was conducted.The calculation was based on the continuity equation and Reynolds-averaged Navier-Stokes equation.The control equation was solved by using standard k-e turbulence mode and SIMPLEC algorithm.The three-dimensional turbulent flow fields in high-speed centrifugal pumps with ultra-low specific-speed were analyzed in design condition by means of numerical simulation.When different types of complex impellers were used.The best combination of the radial and circumferential offset position of the short blade was given.The distribution of velocity and pressure in ordinary impeller and complex impeller in different operations were emphatically analyzed and compared.So that the main features of internal flow in two types of impellers were given.It was found that the performance of complex impeller with short and long blades was better than that of ordinary conventional impeller when other flow-passage components were identical.