PIV investigations of the flow field over a NACA 0012 airfoil pitching under deep dynamic stall conditions

Abstract

The unsteady flowfield above a NACA 0012 airfoil pitching under deep dynamic stall conditions has been investigated in a low-speed wind tunnel by means of Particle Image Velocimetry measurements. The results show the characteristic features of the dynamic stall process: formation and development of an organized vortex structure for increasing incidences, subsequent separation and complex flow behaviour during the downstroke regime. Furthermore, small-scale structures could be obtained in the separated flowfield and even within the dynamic stall vortex. These results can be considered to be a good data basis for the validation of numerical codes.