Numerical Optimization of Silent Airfoil Sections

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 performance. 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 and aeroacoustic measurements conducted in the Laminar Wind-Tunnel of the IAG have shown that the accurate prediction of boundarylayer history and anisotropy effects have a decisive impact on the consistency of the noise prediction. The aerodynamic analysis method was extended to better account for these aspects. Extensive validations demonstrated the enhancements.