Evaluation of different methods for determining the angle of attack on wind turbine blades with CFD results under axial inflow conditions

摘要

This work presents an investigation on different methods for the calculationof the angle of attack and the underlying induced velocity on wind turbineblades using data obtained from three dimensional computational fluid dynamics.Several methods were examined and their advantages as well as shortcomings werepresented. The investigations were performed for flows past two 10MW referencewind turbines under axial inflow conditions, namely the 10MW turbines designedin the EU AVATAR and INNWIND.EU projects. The results shown that the evaluatedmethods are in good agreement with each other at the mid-span, though somedeviations were observed at the root and tip regions of the blades. Using anyof the proposed methods, it is possible to obtain airfoil characteristics forlift and drag coefficients as a function of the angle of attack. Furthermore,by using the extracted data new correction models can be derived for bladeelement momentum calculations.