Entropy production analysis of energy loss of centrifugal pump impeller with multi-objective optimization

Efficiency is the core index for evaluating centrifugal pumps, which reduces the overall energy power loss of the pump and enhances the economics. The efficiency and energy-saving performance of the pump can be improved with an optimal designed impeller. In this paper, the efficiency improvement optimization design method for pumps is proposed via the pump impeller multi-parameter multi-objective optimization. Firstly, the high accuracy simulation model of the pump is modelled and verified. Comparison with the experimental results verifies the accuracy of the numerical method. Then, the design parameters of the impeller blades are hub inlet angle of impeller β 1h , shroud inlet angle of impeller β 1s , outlet angle of impeller β 2 , shroud leading edge LEs, hub leading edge LEh for as the optimal parameters for orthogonal design. As the result, the optimized pump efficiency is increased by 1.902% and head is increased by 0.931 m. The optimized impeller mitigates unstable vortex clusters at the trailing edges of the blades, resulting in a more uniform velocity distribution and reduced flow separation within the impeller. The vortex transport equation was employed to investigate changes in the vortex structure. Additionally, the energy loss associated with the optimized impeller was evaluated using entropy production. Results show that optimizing the impeller reduces entropy production in both the impeller and the pump, thereby minimizing overall energy loss. These findings highlight the primary sources of energy loss in the impeller as potential focal points for further optimization research.