Numerical Analysis of the Influence of Tip Devices on the Power Coefficient of a VAWT

The aerodynamic performances of vertical axis wind turbines are highly affected by tip vortexes. In the present work, different tip devices are considered and simulated against a baseline rotor configuration, with the aim of identifying the best tip architecture. Three different configurations are tested: winglets, an elliptic termination and an aerodynamic bulkhead. A comparative analysis on the most promising architectures is conducted, focusing also on blade torque evolution during a full revolution of the rotor blade. The most promising technology is concluded to be a well designed winglet.

Authors:

• Federico Amato
• Gabriele Bedon
• Marco Raciti Castelli
• Ernesto Benini

Keywords:

• Darrieus Wind Turbine
• Tip Devices
• Tip Vortexes
• Winglet
• Elliptic Termination
• Aerodynamic Bulkhead

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