OPTICAL VORTEX TRACKING STUDIES OF A HORIZONTAL-AXIS WIND TURBINE IN YAW USING LASER-SHEET, FLOW VISUALIZATION

Experimental studies have been conducted on a 0.9 m diameter, horizont al axis wind turbine (HAWT) placed in the open jet of a closed return wind tunnel. The turbine was tested in a three blade and a two blade c onfiguration. The power coefficient of the turbine was measured and wa ke how studies conducted for a range of yawed flows by tilting the rot or plane at various angles up to 30 degrees to the incident wind direc tion. The motion of the shed vorticity was followed using laser-sheet flow visualisation with the overall wake deflection being measured. Th e results were compared with theoretical predictions and with studies conducted elsewhere.