**Airfoil Boundary Layer Optimization Toward Aerodynamic Efficiency of Wind Turbines** Airfoil Boundary Layer Optimization Toward

DOI: 10.5772/intechopen.70895

Aerodynamic Efficiency of Wind Turbines

Youjin Kim, Ali Al-Abadi and Antonio Delgado

Additional information is available at the end of the chapter Youjin Kim, Ali Al-Abadi and Antonio Delgado

http://dx.doi.org/10.5772/intechopen.70895 Additional information is available at the end of the chapter

#### Abstract

Local aerodynamic defects were found in the area of the rotation units of both wings. A longitudinal vortex along the left side of fuselage was observed. It is generated due to model asymmetry so that the right wings are higher than the left ones. It was shown that this vortex

Due to UAV longitudinal instability for small wings rotation angles, low time of wings unfold-

Further research might include UAV dynamics modelling based on calculated aerodynamics

\*

[1] Switchblade: Not a UAV to Mess With [Internet]. March, 10, 2009. Available from: www.deepbluehorizon.blogspot.com/2009/03/switchblade-not-uav-to-mess-with.html

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[6] Boждaeв BB. Bлияниe мoдeли туpбулeнтнocти нa тoчнocть pacчeтa aэpoдинaми чecкиx xapaктepиcтик мexaнизиpoвaннoгo кpылa. [Turbulence model effect on the calculation tolerance of aerodynamic characteristics of wing with high-lift devices].

2 National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute",

and Oleksandr M. Masko2

\*Address all correspondence to: maska310@ukr.net

1 Antonov Company, Kyiv, Ukraine

[Accessed: 2015-03-09]

uncategorized [Accessed: 2017-01-28]

Texникa вoздушнoгo флoтa. 2011;**3**:16-22

of ideas)]. Haучнo-тexничecкиe вeдoмocти. 2004;**2**:7-20

2017-01-28]

does not result in significant roll moment.

84 Flight Physics - Models, Techniques and Technologies

ing is required.

**Author details**

Illia S. Kryvokhatko1

Kyiv, Ukraine

**References**

characteristics or flight tests.

This chapter describes the method of airfoil optimization considering boundary layer for aerodynamic efficiency increment. The advantages of laminar boundary layer expansion in airfoil of horizontal axis wind turbine (HAWT) blades are presented as well. The genetic algorithm (GA) optimization interfaced with the flow solver XFOIL was used with multiobjective function. The power performance of turbine with optimized airfoil was calculated by using blade element method (BEM) in software QBlade. The CFD simulation from OpenFOAM® with Spalart-Allmaras turbulence model showed the visualized airflow. The optimized airfoil shows enlarged laminar boundary layer region in all flow regime with a higher aerodynamic efficiency and the increased gliding ratio (GR). The power velocity and annual energy production (AEP) curves show the performance improvement of wind turbine with the optimized airfoil. The boundary layer thickness and skin-friction coefficient values support the decreased drag of the optimized airfoil. The smaller laminar separation bubbles and reduced stall regime of CFD simulations illustrate the desirable aerodynamics of the resulted airfoil.

Keywords: aerodynamics, airfoil, drag and lift, separation, transition
