A Comparative Study of Flow Control Methods for Enhancing Wind Turbine Blade Performance

Over the last 20 years, multiple flow control methods have emerged, presenting significant improvements over conventional blades. Despite this progress, comparisons of different flow control methods are still limited. Therefore, the current study aims to investigate the lift and drag performances of the flow controls, namely, a Gurney flap, guided vane, microplate, slat, and spoiler at fixed parameters. The study initially developed a numerical model, which was subsequently validated against previous experimental and numerical studies. After obtaining an accurate numerical model, the model was modified and tested with the flow control methods. The finding mainly highlighted that the slat has higher performance than the baseline airfoil, followed distantly by the microplate, Gurney flap, guided vane, and spoiler. The slat achieved the highest performance, showcasing a 27.35% improvement. The detailed simulation results also revealed the presence of the Coanda and orifice effects in the airflow, which significantly affect the performance. An extensive investigation was conducted to explore dual combinations of selected flow control methods to identify the optimum combination that could offer higher improvement. Among nine combinations tested, the combination of the Gurney flap and microplate exhibited higher performance than the other combinations, achieving a 29.88% enhancement.