This study investigates the novel application of pitch control to a troposkein-shaped Darrieus vertical axis wind turbine (VAWT). Results indicate that pitching only a partial blade span and/or struts can regulate rated power, increase annual energy production (AEP) and reduce fatigue loads. The findings of this study lay the foundation for promising new operating strategies using partial-span blade pitch and/or strut pitch control for troposkein-shaped Darrieus VAWTs.

Though large wind turbines are appealing to reduce costs, larger blades are prone to aero-elastic instabilities due to their long, slender, highly flexible nature. New rotor concepts are emerging including two-bladed rotors and downwind configurations. We introduce a comprehensive evaluation of flutter behavior including classical flutter and edgewise vibration for large-scale two-bladed rotors. The study aims to provide designers with insights to mitigate flutter in future designs.

This paper presents a comprehensive aerodynamic design study for a 5 MW Darrieus offshore VAWT in the context of multi-megawatt floating VAWTs. This study systematically analyzes the effect of different, important design variables including the number of blades, aspect ratio and blade chord tapering in a comprehensive load analysis of both the parked and operating aerodynamic loads including turbine power performance analysis using a vortex-based aerodynamic model.