Airfoil Blender for Blade Optimizations

An airfoil database was developed in the present work. The database includes a multivariate, unstructured grid, Radial Basis Function (RBF), optimization-compatible interpolator for airfoil aerodynamic coefficients. The database was designed to aid complex blade design optimizations carried out in a novel optimization framework, HAWTOpt2, being currently developed at DTU Wind Energy.

In the database, the lift, drag and moment coefficients are stored as functions of airfoil family, thickness, Reynolds number and angle of attack. Aerodynamic add-ons and airfoil modifications are included in the database as separate airfoil families. Additionally, the database includes two different 3D correction methods and two different 360 degree extrapolation methods.

Further, the database stores airfoil coordinates as functions of airfoil family and thickness. Those coordinates may also be interpolated using the RBF method. Present work included a demonstration of the coefficient interpolator in an optimization aimed at indicating the optimal layout of Vortex Generators on eroded blades of the DTU 10MW Reference Wind Turbine in order to maximize the Annual Energy Production.