Water Resources and Power

A new type of MBC impellerr with a guide vane slot structure was proposed to improve the energy capture and wave reduction efficiency of Savonius-type(S-type) impeller. A multi-objective optimization algorithm combined BP neural network, NSGA-Ⅱ, numerical simulation and experimental test was used to optimize five parameters of the MBC impeller including overlap ratio, gap ratio, internal and external arc angle, internal arc radius, and guide vane size. The performance of the optimal MBC impeller was compared with that of the S-type and MB-type impellers. The results show that the prediction error of the relevant performance values is less than 10% compared to the actual values, verifying the good performance of the established prediction model. The obtained optimal parameters are: overlap ratio of 0.136, gap ratio of 0.003, internal and external arc angle of 5.23°, internal arc radius of 41.42 mm, and guide vane size of 2.83 mm. Compared with the traditional S-type impeller, the optimal MBC impeller has increased energy capture efficiency by 35.8% and wave reduction efficiency by 11%.