Evaluation of active flow control applied to wind turbine blade section

A feasibility study for implementing active flow control (AFC) methods to improve the performance of wind turbines was performed. The experimental effort investigated the impact of zero-mass-flux (ZMF) piezofluidic actuators attempting to control boundary layer separation from thick airfoils that are suitable for wind turbine rotor blades. It was demonstrated that the ZMF actuators can replace passive vortex generators that are commonly used for boundary layer separation delay, without the inherent drag penalty that the passive devices impose. It has been shown that ZMF fluidic actuators are suitable for flow control in wind turbine application due to the fact that they are adjustable for wider Reynolds number range, while vortex generators are tuned to perform well in one design point. It was demonstrated that AFC can effectively double the maximum lift of this airfoil at low Reynolds numbers. A possible application is a significant reduction of the turbine start-up velocity. It was also found that even ...

[1]  N. Didden On the formation of vortex rings: Rolling-up and production of circulation , 1979 .

[2]  Avi Seifert,et al.  Maneuvering Aspects and 3D Effects of Active Airfoil Flow Control , 2004 .

[3]  Avi Seifert,et al.  Use of Piezoelectric Actuators for Airfoil Separation Control , 1998 .

[4]  G.A.M. van Kuik,et al.  State of the art and prospectives of smart rotor control for wind turbines , 2007 .

[5]  Avi Seifert,et al.  Active Control of a Circular Cylinder Flow at Transitional Reynolds Numbers , 2007 .

[6]  John C. Lin,et al.  Review of research on low-profile vortex generators to control boundary-layer separation , 2002 .

[7]  M. Amitay,et al.  Role of Actuation Frequency in Controlled Flow Reattachment over a Stalled Airfoil , 2002 .

[8]  James P. Johnston,et al.  Vortex Generator Jets—Means for Flow Separation Control , 1990 .

[9]  I. Wygnanski,et al.  Delta wing stall and roll control using segmented piezoelectric fluidic actuators , 2005 .

[10]  V. M. F. B.Sc.,et al.  LXXXV. Solutions of the boundary-layer equations , 1931 .

[11]  Ari Glezer,et al.  Direct excitation of small-scale motions in free shear flows , 1998 .

[12]  A. Seifert,et al.  Active Flow Separation Control on Wall-Mounted Hump at High Reynolds Numbers , 2002 .

[13]  H. Schlichting Boundary Layer Theory , 1955 .

[14]  J. Bons,et al.  Turbine Separation Control Using Pulsed Vortex Generator Jets , 2000 .

[15]  S. Chandrasekhar Hydrodynamic and Hydromagnetic Stability , 1961 .

[16]  A. Seifert,et al.  Oscillatory Control of Separation at High Reynolds Numbers , 1999 .

[17]  W. A. Timmer,et al.  Summary of the Delft University Wind Turbine Dedicated Airfoils , 2003 .

[18]  I. Wygnanski,et al.  Delay of Airfoil Stall by Periodic Excitation , 1996 .

[19]  I. Tani Low-speed flows involving bubble separations , 1964 .