Optimization design on blade with bionic protuberances of horizontal axis wind turbine

Abstract

The operating conditions of wind turbines are changeable, and the flow separation limits the power generation capacity. In order to improve the output power of wind turbines, based on the principle of bionics, the leading-edge protuberance (LEP) of the humpback whale flipper is introduced to the blade. The optimization of LEP parameters and distribution on the blade performance is studied. The shape and distribution of nonlinear, non-uniform LEPs are controlled by three design variables: amplitude, attenuation, and number. The optimization system consists of modules such as model generation, computational fluid dynamics, and genetic algorithm. The results show that the optimized bionic wind turbine can increase the output power by 3.95% under the rated condition. The optimized LEP structure can improve the performance of the trough sections without sacrificing part of the performance of peak sections, with a maximum increase of 20%. The theory of entropy production is used to analyze the location of energy loss and its impact on the wake. The distribution of the local entropy production rate of the wind turbine wake after optimization is improved. The power spectral density analysis shows that the LEPs cause different variation laws in the wake from the original wind turbine.