Scale-Adaptive Simulation (SAS) of Dynamic Stall on a Wind Turbine

Scale-adaptive simulation (SAS) approach is employed to investigate the complex dynamic stall phenomena occurring on a wind turbine blade. The results are com-pared with the more popular less computationally-expensive unsteady Reynolds-averaged Navier-Stokes (URANS) approach where the latter is validated using three sets of experimental data. The comparison reveals that the two approaches have similar predictions of the instant of the formation/bursting/shedding of the laminar separation bubble (LSB) and dynamic stall vortex (DSV), the size of the LSB and aerodynamic loads during the upstroke. This is while the two approach-es exhibit dissimilar predictions of the trailing-edge vortex characteristics, its in-teraction with the DSV, number of secondary vortices and aerodynamic loads during the downstroke.