Effect of Leading Edge Radius and Blending Distance from Leading Edge on the Aerodynamic Performance of Small Wind Turbine Blade Airfoils

Abstract

The aerodynamic performance of a wind turbine depends upon shape of blade profile blade airfoils. Today, small wind turbine industries are extensively focusing on blade performance, reliability, materials and cost. The wind turbine blade designers are required to give emphasis on accurate analysis of flows around the blade and loads on wind turbine blades. Low Reynolds number airfoils suited for small wind turbine applications must be designed to have a high degree of tolerance in avoiding high leading suction peaks and high adverse pressure gradients that lead to flow separation. This paper presents a study to investigate the effect of leading edge radius and leading edge blending on the aerodynamic performance of wind turbine airfoils. In the present work NACA 4412 airfoil is considered as base airfoils. In this work six modified airfoils having different new to the old ratio of leading edge radii are considered for performance analysis. The performance of these six profiles is compared with basic airfoil performance. In this paper, the effect of blending distance from leading edge of airfoil on aerodynamic performance is also determined. Different five blending distances from leading edge are analyzed and compared with basic profile. The performance analysis of airfoils is carried out using Blade Element Momentum. In the present analysis, chord length of airfoils and Reynolds number are kept constant.