Numerical Optimization of Silent Airfoil Sections
Th. Lutz, W. Würz, A. Herrig, K. Braun and S. Wagner
DEWEK 2004, 7th German wind energy conference, Wilhelmshaven, October 20/21, 2004
Within the work of the EU-funded SIROCCO project new airfoils for the tip region of two reference wind turbines are being designed with the objective to reduce the trailing-edge noise while maintaining the perfomance. The present paper focuses on the description of the optimization tools along with the aerodynamic and aeroacoustic prediction methods used. Comparisons with detailed boundary-layer experiments ans aeroacoustic measurements conducted in the Laminar Wind-Tunnel of the IAG have shown that the accurate prediction of boundary-layer history and anisotropy effects have a decisive impact in the consistency of the noise prediction. The aerodynamic analysis method was extended to better account for these aspects. Extensive validations demonstrated the enhancements.