Improvements in performance estimation of wind turbine blade at low Reynolds number

In this paper we propose a comparison between two Reynolds–Averaged–Navier–Stokes (RANS) turbulence models as Spalart–Allmaras (S–A) and the more recent transitional k–w SST in descibing low Reynolds number laminar bubble bursting stall for three different airfoils: a NACA 0012 used as reference airfoil with a well known behaviour and a NACA 0018, widely used on many vertical–axis–wind–turbine (VAWT), of which TU Delft recent experimental data al low Reynolds number are available. Finally an extension to higher Reynold number is proposed with an analysis on S809 airfoil. Emphasys is posed on different turbulence models desciption of experimental physical condition such as turbulence intensity and flow field description of laminar separation inside bubble.