Design and Optimum arrangement of a Blade Flap for Improving the Power Generation of a Horizontal Axis Wind Turbine

In this research, a new type of add-on flap is presented and the effect of adding it to the blade of a horizontal axis wind turbine and optimizing its location and length is investigated. The use of an add-on flap is more cost-effective than other conventional methods since it does not need major modifications to the existing blades. For increasing the accuracy of the blade element momentum algorithm, the aerodynamic coefficients of the blade section are obtained by numerical solution of the governing equations, while in most similar studies, methods based on airfoil linear theory were used. The results showed that the modification made in the blade momentum element algorithm increased the accuracy of the solver while maintaining its computational speed. The results show that using this type of flap arrangement, the value of the base turbine power coefficient was increased from 0.29 to 0.41, which shows a significant increase compared to other methods.