TY - JFULL AU - M. Raciti Castelli and G. Grandi and E. Benini PY - 2012/4/ TI - Numerical Analysis of Laminar to Turbulent Transition on the DU91-W2-250 Airfoil T2 - International Journal of Aerospace and Mechanical Engineering SP - 716 EP - 724 VL - 6 SN - 1307-6892 UR - https://publications.waset.org/pdf/12816 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 63, 2012 N2 - This paper presents a study of laminar to turbulent transition on a profile specifically designed for wind turbine blades, the DU91-W2-250, which belongs to a class of wind turbine dedicated airfoils, developed by Delft University of Technology. A comparison between the experimental behavior of the airfoil studied at Delft wind tunnel and the numerical predictions of the commercial CFD solver ANSYS FLUENT® has been performed. The prediction capabilities of the Spalart-Allmaras turbulence model and of the γ-θ Transitional model have been tested. A sensitivity analysis of the numerical results to the spatial domain discretization has also been performed using four different computational grids, which have been created using the mesher GAMBIT®. The comparison between experimental measurements and CFD results have allowed to determine the importance of the numerical prediction of the laminar to turbulent transition, in order not to overestimate airfoil friction drag due to a fully turbulent-regime flow computation. ER -