Function of the turbo‐sail airfoil applied to the Darrieus wind turbine
Yoshimichi Ono,
Ryosuke Sayama,
Yuichi Murai,
Hyun Jin Park,
Yuji Tasaka
Affiliations
Yoshimichi Ono
Laboratory for Flow Control, Division of Mechanical and Aerospace Engineering, Faculty of Engineering Hokkaido University N13W8 Sapporo Hokkaido 0608628 Japan
Ryosuke Sayama
Laboratory for Flow Control, Division of Mechanical and Aerospace Engineering, Faculty of Engineering Hokkaido University N13W8 Sapporo Hokkaido 0608628 Japan
Yuichi Murai
Laboratory for Flow Control, Division of Mechanical and Aerospace Engineering, Faculty of Engineering Hokkaido University N13W8 Sapporo Hokkaido 0608628 Japan
Hyun Jin Park
Laboratory for Flow Control, Division of Mechanical and Aerospace Engineering, Faculty of Engineering Hokkaido University N13W8 Sapporo Hokkaido 0608628 Japan
Yuji Tasaka
Laboratory for Flow Control, Division of Mechanical and Aerospace Engineering, Faculty of Engineering Hokkaido University N13W8 Sapporo Hokkaido 0608628 Japan
Abstract The use of a turbo‐sail airfoil to improve the power generation of a Darrieus wind turbine was examined. The turbo‐sail airfoil comprises a symmetric blade from which a high‐speed tangential jet is produced to suppress flow separation. For a steady angle of attack, we experimentally confirmed an anti‐stall function of the airfoil at an angle of attack up to and exceeding 30°. Considering the case of the rotation of a single blade of a Darrieus wind turbine, the flow field was replaced with a non‐separated stream around the airfoil particularly even at a tip‐speed ratio lower than 3. The pressure field and local lift‐to‐drag ratio measured by particle image velocimetry quantitatively supported the expected anti‐stall function. Improvements in the torque and power coefficient were estimated from measurements considering the external power consumed in supplying the jet.
