Aerodynamic Analysis of Flow-Control Devices for Wind Turbine Applications Based on the Trailing-Edge Slotted-Flap Concept

AbstractThe development of upscaled wind turbines of tomorrow would benefit from a rationale change in load-control strategies. Active flow-control devices attached to existing blade designs constitute an interesting alternative. This study presents a numerical assessment of the aerodynamic characteristics of airfoil sections specifically intended for wind turbine applications, with modular flow-control devices attached. Based on the slotted trailing-edge flap concept, these modular devices could be appended to an existing blade design, providing a cost-effective method of active control with low energy of actuation. Their use also requires minimal design modifications to the original blade and retooling of its manufacturing process. Numerical results are presented for the study of the effects of slotted flaps applied to two airfoil sections, the NACA 643−618 and the DU 93-W-210, which are currently used on the NREL-5MW reference wind turbine. By adding new knowledge about the effects of flaps applied to ...

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