Influence of Prewhirl Angle and Axial Distance on Energy Performance and Pressure Fluctuation for a Centrifugal Pump with Inlet Guide Vanes

The energy performance and pressure fluctuations in a centrifugal pump with inlet guide vanes (IGVs) are investigated experimentally and numerically in a prewhirl angle range of −24◦ to 24◦ and in an axial distance range of 280 mm, 380 mm, and 460 mm. The reliability and accuracy of the numerical method are validated by the satisfactory agreement between the experimental data and numerical results. Prewhirl regulation with IGVs can significantly increase the energy performance and broaden the efficient operation range for the centrifugal pump due to the improvement of flow pattern at the impeller inlet. The prewhirl angle has an obvious impact on pump energy performance, and the maximum amplitudes of pressure fluctuations on the blade leading edge of the pressure and suction sides decrease by 69% and 89%, respectively. The axial distance has a slight impact on pump energy performance, but the maximum amplitudes of pressure fluctuations drop by 35.4% on the blade leading edge of pressure side when the axial distance extends from 280 mm to 460 mm.