Experimental study on the hydraulic design of pool pumps and the effect of impeller balance holes on pump performance

To study the design method of pool centrifugal pumps and the feasibility of drilling balance holes, upon the summary of six excellent hydraulic models, this paper proposed an innovative VCM (velocity-coefficient method)-based hydraulic design method for optimizing cavitation performance of centrifugal pumps. This innovative method has been field-proven with high accuracy and practicability. Based on that, a pool centrifugal pump type was developed with a specific speed of up to 175 rps, and the hydraulic design process and outcomes were elaborated. Moreover, the effect of balance holes on pump performance was discussed, and based on the SST k-ω turbulence model, the performance-axial force curves were plotted under different flow rate conditions of the modeled pumps with and without balance holes upon computations in the numerical simulation models of pool pumps established through the finite volume method (FVM). The analysis shows that balance holes are conducive to a decrease in the axial force by up to 19.6% but greatly affect pump performance due to their hydraulic characteristics. This paper provides a constructive scientific basis for optimizing design and improving the reliability of centrifugal pumps.