Experimental investigation and numerical analysis on horizontal axis wind turbine with winglet and pitch variations

HAWT with three blades often used because it has the highest coefficient of performance among other turbines. The airfoil used is Clark-Y type because it has a high glide ratio (coefficient lift/coefficient drag) in the application of subsonic flow. The main purpose of this study is to increase the power coefficient value obtained by the increase of lift force on each airfoil of blade compiler and to fix the wind turbine performance. One of the variations added is the addition of winglets on the tip of the blade. The method employed is a laboratory scaled experiment by using wind tunnel. Theoretically, this study also applied blade element momentum (BEM) as the calculation of each segment on the airfoil, and the simulation was carried out with computational fluid dynamics (CFD), in order to find out the characteristics of flow passing by the rotor. The advantage of using winglets is, fostering the condition of starting wind turbine rotor on low tip speed ratio (TSR) condition by varying the pitch angle on the blade. The addition of pitch variation gives an advantage that it can maximize the wind speed towards the angle of attack to the airfoil; hence, it increases the aerodynamic effect on the rotor.