Design and Analysis of Horizontal Axis Wind Turbine Blade with Winglet

Abstract

Kerala is blessed with abundance of wind energy sources offering wide possibilities for installing wind farms. But the literature survey shows that this renewable energy source is not effectively utilized due to the strenuous transportation and installation issues along with the public protest regarding the noise pollution, whereas reducing the blade length will inversely affect the output power generation. The present work focuses on reducing the blade length without compromising the output power generated. A horizontal axis wind turbine (HWAT) with winglets is proposed. The addition of winglet results in reducing the induced drag thereby increasing the efficiency and generates the same power output with a compact design incorporated with noise reduction due to elimination of tip vortices. The selection of different airfoil shapes from NACA series was done and blade aerodynamics was simulated to investigate the flow structures and general aerodynamic coefficients are extracted using ANSYS software. A comparison of aerodynamic performance of different airfoil geometries is done to find a suitable airfoil shape based on L/D characteristics. 3D model analysis of blade from selected airfoil cross section, with and without winglet is carried out using ANSYS Fluent and the aerodynamic performance is compared to study the effectiveness of the winglet. It is found that the blade with winglet gives higher performance compared to the one without winglet for a given wing span. The effect of winglet geometry and cant angle are also analyzed to arrive at an optimum winglet dimension for a reduced wingspan.