Water channel experiments of dynamic stall on Darrieus wind turbine blades

Abstract

An experimental study of periodic vortex phenomena was performed on a model of a two straight-bladed Darrieus wind turbine under controlled-rotation conditions in the Institute de Mechanique et Statistique de la Turbulence (IMST) water channel. The study focused on the tip-speed ratios at which dynamic stall appears. Observations of this phenomenon were made using dye emission and the hydrogen bubbles and photographs, movies, and video recordings were made. Velocity measurements were obtained using the laser-doppler velocimeter and the components of velocity fluctuations were determined quantitatively.