Bioinspired curved blade for darrieus vertical axis wind turbine: A novel conceptual design and experimental investigation

The present study proposes a novel bio-inspired blade design to improve the efficiency of a VAWT model. The design model features a curved blade that sweeps backward, same characteristics as the Bottlenose Dolphin’s flippers. The proposed model would enhances aerodynamic flow over the system and improves torque. The modified shape can cause the fluid flow to converge towards the middle of the blade due to the pressure difference caused by the modified blade profile. Three modified shapes have been studied experimentally to observe the effect of swept curved design with a forward sweep of 0.2 c, 0.6 c, and 1.0 c for these augmented models. A wind-driven performance analysis mode is performed in a subsonic wind tunnel. A maximum of 15.7% increment in torque is observed for the model having a sweep of 1.0 c, and a maximum of 15% Coefficient of performance ( C P ) is observed by Model D at tip speed ratio ( TSR, λ) = 1.8. An increment of 12% is observed in C P between the conventional and the modified model.