Abstract: Centrifugal impellers C1, C2 and C3 are designed by using of three-order blade profile with the same basic geometry, such as radius, blade width and angle in the inlet and outlet, the number of the blades, and the designed rotating speed is also the same. The wrap angle of C1, C2 and C3 is 59°, 75° and 91° respec-tively. The profile of impeller C1 is very close to the ones of traditional single-arc. The test results indicate that the best efficiency of C2 is 1.28%, 1.43% higher than C1 and C3 respectively. By numerical simulation at the designed flow rate, the distribution of the relative velocity and load in the impeller is obtained. In the impeller C1 there is recirculation flow and load distribution in different passage is different. The study indicates that there is a best wrap angle and the single-arc is not the best blade profile.

Key words: Centrifugal pump, Experimental measurement, Numerical simulation