Abstract: The impact of gap drainage blades’ position on the hydraulic performance of a low specific speed centrifugal pump is studied. A fully automatic integrated optimization platform is used, which includes blades parametric design, meshing, computational fluid dynamics (CFD) calculations and post-processing. The hydraulic efficiency maximization of a centrifugal pump impeller is taken as the objective function. Design of experiments (DOE) and sequential quadratic programming (SQP) are used for optimal design. The comparison between the optimal impeller and the original impeller shows that the jam effect has been reduced, and the head improved. Specifically, efficiency of the optimal impeller is higher than the original after the condition 0.6Q, and the maximum efficiency point is improved by 2%. The results indicate feasibility of the design method.

Key words: gap drainage blade, low specific speed, optimal design;combined strategy, parameterization