Abstract: In order to study on hydraulic performance of slanted 15° axial pumping system, the three dimensional steady turbulent flow in pumping system is simulated based on computational fluid dynamics software ANSYS CFX, applying the RNG k-ε turbulent flow model, scalable wall functions and the multiple reference frames. The flow detail of the whole slanted axial pumping system is attained. The relation between hydraulic performance of outlet cross sections with rotating impeller and the relative height of outlet cross sections and the stress distribution of impeller are analyzed, as well as the relative velocity distribution near the airfoil cross sections under the designed condition. The hydraulic moments are calculated based on the numerical results under different conditions，and the changing features of hydraulic moment on blades with flow rates are analyzed. The reference nominal height of pumping system can be marked from (0.7-0.9) D. The comparison of simulation results and experiment data show that the biggest absolute error is 5.01% between predictive and experimental pumping system efficiency, especially the relative error of head and the absolute error of efficiency are less than 3.5% at the best efficiency and designed operating conditions, which validate the validity of the numerical simulation.

Key words: Hydraulic machinery, Hydraulic moment, Hydraulic performance, Performance test, Pumping system