The development of a flatback wind turbine airfoil family

Abstract

AbstractFlatback airfoils show several potential benefits in the design of wind turbine blades. Structurally, the increased trailing‐edge thickness offers high resistance to flapwise bending, while aerodynamically, a higher maximum coefficient of lift, as well as better roughness insensitivity, may be achieved. In this work, the design of a flatback airfoil family is performed with a high degree of attention to the appropriate selection of design constraints and objectives. Through the analysis of other airfoils available in the literature, and through sensitivity analyses of several design parameters, the CU‐W1‐XX airfoil family is designed. The optimization tool used in this work consists of a genetic algorithm in which the airfoil shapes are altered using Bézier curve parameterization. The aerodynamic performance is evaluated using XFOIL while the structural performance is evaluated from the sectional moment of inertia about the chord. In several metrics such as sectional moment of inertia, roughness insensitivity, and lift‐to‐drag ratio, the CU‐W1‐XX family is shown to have equal or superior performance as compared with other airfoils, thus proving the capability of the airfoil optimization tool and, more importantly, the value of proper design constraints and objectives.