Visualization and Image Analysis of Relative Velocity Field around a Blade for Darrieus Wind Turbine

Abstract

The velocity field relative to the rotating blade of a Darrieus wind turbine has been measured by particle imaging velocimetry and the dynamic stall phenomenon of the wind turbine is studied in detail. Three stall vortices are generated in a cycle of rotation and they grow in size with an increase in the blade angle. The measured velocity field around the blade are well reproduced in the flow visualizations by dye injection technique.