National Renewable Energy Laboratory, 1996. - 83 pages.
This study focuses on the use of vortex generators (VGs) for performance augmentation of the stall-regulated AWT-26 wind turbine. The goal was to design a VG array which would increase annual energy production (API1) by increasing power output at moderate wind speeds, without adversely affecting the loads or stall-regulation performance of the turbine.
Wind tunnel experiments were conducted at the University of Washington to evaluate the effect of VGs on the AWT-26 blade, which is lofted from National Renewable Energy Laboratory (NREL) S-series airfoils. Based on wind-tunnel results and analysis, a VG array was designed and then tested on the AWT-26 prototype, designated Pi. Performance and loads data were measured for PI, both with and without VGs installed. The turbine performance with VGs met most of the design requirements; power output was increased at moderate wind speeds with a negligible effect on peak power. However, VG drag penalties caused a toss in power output for low wind speeds, such that performance with VGs resulted in a net decrease in AEP for sites having annual average wind speeds up to 8.5 m/s.
While the present work did not lead to improved AEP for the AWT-26 turbine, it does provide insight into performance augmentation of wind turbines with VGs. The safe design of a VG array for a stall -regulated turbine has been demonstrated, and several issues involving optimal performance with VGs have been identified and addressed.
This study focuses on the use of vortex generators (VGs) for performance augmentation of the stall-regulated AWT-26 wind turbine. The goal was to design a VG array which would increase annual energy production (API1) by increasing power output at moderate wind speeds, without adversely affecting the loads or stall-regulation performance of the turbine.
Wind tunnel experiments were conducted at the University of Washington to evaluate the effect of VGs on the AWT-26 blade, which is lofted from National Renewable Energy Laboratory (NREL) S-series airfoils. Based on wind-tunnel results and analysis, a VG array was designed and then tested on the AWT-26 prototype, designated Pi. Performance and loads data were measured for PI, both with and without VGs installed. The turbine performance with VGs met most of the design requirements; power output was increased at moderate wind speeds with a negligible effect on peak power. However, VG drag penalties caused a toss in power output for low wind speeds, such that performance with VGs resulted in a net decrease in AEP for sites having annual average wind speeds up to 8.5 m/s.
While the present work did not lead to improved AEP for the AWT-26 turbine, it does provide insight into performance augmentation of wind turbines with VGs. The safe design of a VG array for a stall -regulated turbine has been demonstrated, and several issues involving optimal performance with VGs have been identified and addressed.