Numerical Analysis of the Influence of Airfoil Asymmetry on VAWT Performance
This paper presents a model for the evaluation of
energy performance and aerodynamic forces acting on a three-bladed
small vertical axis Darrieus wind turbine depending on blade chord
curvature with respect to rotor axis.
The adopted survey methodology is based on an analytical code
coupled to a solid modeling software, capable of generating the
desired blade geometry depending on the blade design geometric
parameters, which is linked to a finite volume CFD code for the
calculation of rotor performance.
After describing and validating the model with experimental data,
the results of numerical simulations are proposed on the bases of two
different blade profile architectures, which are respectively
characterized by a straight chord and by a curved one, having a chord
radius equal to rotor external circumference. A CFD campaign of
analysis is completed for three blade-candidate airfoil sections, that is
the recently-developed DU 06-W-200 cambered blade profile, a
classical symmetrical NACA 0021 and its derived cambered airfoil,
characterized by a curved chord, having a chord radius equal to rotor
external circumference.
The effects of blade chord curvature on angle of attack, blade
tangential and normal forces are first investigated and then the
overall rotor torque and power are analyzed as a function of blade
azimuthal position, achieving a numerical quantification of the
influence of blade camber on overall rotor performance.
[1] Sheldal, R. E., Klimas, P. C., "Aerodynamic Characteristics of Seven
Symmetrical Airfoil Sections Through 180-Degree Angle of Attack for
Use in Aerodynamic Analysis of Vertical Axis Wind Turbines",
SAND80-2114, Unlimited Release, UC-60.
[2] Stathopoulos, T., "Wind Effects on People", Proceedings of the
International Conference on Urban Wind Engineering and Building
Aerodynamics - Impact of Wind Storm on City Life and Built
Environment, COST Action C14, Von Karman Institute, Rode-Saint-
Genèse (Belgium), 2004.
[3] Jensen, A. G., Franke, J., Hirsch, C., Schatzmann, M., Stathopoulos, T.,
Wisse, J., Wright, N. G., "CFD Techniques - Computational Wind
Engineering", Proceedings of the International Conference on Urban
Wind Engineering and Building Aerodynamics - Impact of Wind and
Storm on City Life and Built Environment - Working Group 2, COST
Action C14, Von Karman Institute, Rode-Saint-Genèse (Belgium),
2004.
[4] Paraschivoiu, I., Wind Turbine Design: With Emphasis on Darrieus
Concept, Polytechnic International Press, Montreal, 2002.
[5] Johnston. S. F. (Editor), Proceedings of the Vertical-Axis Wind Turbine
(VAWT) Design Technology Seminar for Industry, April 1-3, 1980,
Sandia National Laboratories, SAND80-0984, August 1980.
[6] Saeed, F., Paraschivoiu, I., Trifu, O., "Inverse Airfoil Design Method for
Low-Speed Straight-Bladed Darrieus-Type VAWT Applications", 7th
World Wind Energy Conference 2008: Community Power, Kingston,
Ontario, Canada June 24-26th, 2008.
[7] Claessens, M. C., The Design and Testing of Airfoils for Application in
Small Vertical Axis Wind Turbines, M.Sc. Thesis, Faculty of Aerospace
Engineering, delft University of Technology, The Netherlands,
November 9, 2006.
[8] Kadlec, E. G., "Characteristics of Future Vertical Axis Wind Turbines",
Sandia National Laboratories Report SAND79-1068, Nov. 1982;
[9] Strickland, J. H., "The Darrieus Turbine: A Performance Prediction
Model Using Multiple Streamtube", SAND75-0431.
[10] Simao Ferreira, C. J., Bijl, H., van Bussel, G., van Kuik, G., "Simulating
Dynamic Stall in a 2D VAWT: Modeling Strategy, Verification and
Validation with Particle Image Velocimetry Data", The Science of
Making Torque from Wind, Journal of Physics: Conference Series 75,
2007.
[11] Bradshaw, P., Experimental Fluid Mechanics, Cambridge University
Press, 1964.
[12] Fluent Inc., Fluent User-s Manual, pp. 52, 54, 59, 71, 143.
[13] Cummings, R.M., Forsythe, J.R., Morton, S.A., Squires, K.D.,
"Computational Challenges in High Angle of Attack Flow Prediction",
2003, Progr Aerosp Sci 39(5):369-384;
[14] Raciti Castelli, M., Ardizzon, G., Battisti, L., Benini, E., Pavesi, G.,
"Modeling Strategy and Numerical Validation for a Darrieus Vertical
Axis Micro-Wind Turbine", IMECE2010-39548.
[15] Raciti Castelli, M., Benini, E., "Comparison of Two Airfoil Sections for
Application in Straight-Bladed Darrieus VAWT", submitted for
publication to: World Academy of Science, Engineering and
Technology on September 28, 2011.
[16] Raciti Castelli, M., Englaro, A., Benini, E., "The Darrieus Wind
Turbine: Proposal for a New Performance Prediction Model Based on
CFD", Energy 36 (2011) 4919-4934.
[1] Sheldal, R. E., Klimas, P. C., "Aerodynamic Characteristics of Seven
Symmetrical Airfoil Sections Through 180-Degree Angle of Attack for
Use in Aerodynamic Analysis of Vertical Axis Wind Turbines",
SAND80-2114, Unlimited Release, UC-60.
[2] Stathopoulos, T., "Wind Effects on People", Proceedings of the
International Conference on Urban Wind Engineering and Building
Aerodynamics - Impact of Wind Storm on City Life and Built
Environment, COST Action C14, Von Karman Institute, Rode-Saint-
Genèse (Belgium), 2004.
[3] Jensen, A. G., Franke, J., Hirsch, C., Schatzmann, M., Stathopoulos, T.,
Wisse, J., Wright, N. G., "CFD Techniques - Computational Wind
Engineering", Proceedings of the International Conference on Urban
Wind Engineering and Building Aerodynamics - Impact of Wind and
Storm on City Life and Built Environment - Working Group 2, COST
Action C14, Von Karman Institute, Rode-Saint-Genèse (Belgium),
2004.
[4] Paraschivoiu, I., Wind Turbine Design: With Emphasis on Darrieus
Concept, Polytechnic International Press, Montreal, 2002.
[5] Johnston. S. F. (Editor), Proceedings of the Vertical-Axis Wind Turbine
(VAWT) Design Technology Seminar for Industry, April 1-3, 1980,
Sandia National Laboratories, SAND80-0984, August 1980.
[6] Saeed, F., Paraschivoiu, I., Trifu, O., "Inverse Airfoil Design Method for
Low-Speed Straight-Bladed Darrieus-Type VAWT Applications", 7th
World Wind Energy Conference 2008: Community Power, Kingston,
Ontario, Canada June 24-26th, 2008.
[7] Claessens, M. C., The Design and Testing of Airfoils for Application in
Small Vertical Axis Wind Turbines, M.Sc. Thesis, Faculty of Aerospace
Engineering, delft University of Technology, The Netherlands,
November 9, 2006.
[8] Kadlec, E. G., "Characteristics of Future Vertical Axis Wind Turbines",
Sandia National Laboratories Report SAND79-1068, Nov. 1982;
[9] Strickland, J. H., "The Darrieus Turbine: A Performance Prediction
Model Using Multiple Streamtube", SAND75-0431.
[10] Simao Ferreira, C. J., Bijl, H., van Bussel, G., van Kuik, G., "Simulating
Dynamic Stall in a 2D VAWT: Modeling Strategy, Verification and
Validation with Particle Image Velocimetry Data", The Science of
Making Torque from Wind, Journal of Physics: Conference Series 75,
2007.
[11] Bradshaw, P., Experimental Fluid Mechanics, Cambridge University
Press, 1964.
[12] Fluent Inc., Fluent User-s Manual, pp. 52, 54, 59, 71, 143.
[13] Cummings, R.M., Forsythe, J.R., Morton, S.A., Squires, K.D.,
"Computational Challenges in High Angle of Attack Flow Prediction",
2003, Progr Aerosp Sci 39(5):369-384;
[14] Raciti Castelli, M., Ardizzon, G., Battisti, L., Benini, E., Pavesi, G.,
"Modeling Strategy and Numerical Validation for a Darrieus Vertical
Axis Micro-Wind Turbine", IMECE2010-39548.
[15] Raciti Castelli, M., Benini, E., "Comparison of Two Airfoil Sections for
Application in Straight-Bladed Darrieus VAWT", submitted for
publication to: World Academy of Science, Engineering and
Technology on September 28, 2011.
[16] Raciti Castelli, M., Englaro, A., Benini, E., "The Darrieus Wind
Turbine: Proposal for a New Performance Prediction Model Based on
CFD", Energy 36 (2011) 4919-4934.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:55965", author = "Marco Raciti Castelli and Giulia Simioni and Ernesto Benini", title = "Numerical Analysis of the Influence of Airfoil Asymmetry on VAWT Performance", abstract = "This paper presents a model for the evaluation of
energy performance and aerodynamic forces acting on a three-bladed
small vertical axis Darrieus wind turbine depending on blade chord
curvature with respect to rotor axis.
The adopted survey methodology is based on an analytical code
coupled to a solid modeling software, capable of generating the
desired blade geometry depending on the blade design geometric
parameters, which is linked to a finite volume CFD code for the
calculation of rotor performance.
After describing and validating the model with experimental data,
the results of numerical simulations are proposed on the bases of two
different blade profile architectures, which are respectively
characterized by a straight chord and by a curved one, having a chord
radius equal to rotor external circumference. A CFD campaign of
analysis is completed for three blade-candidate airfoil sections, that is
the recently-developed DU 06-W-200 cambered blade profile, a
classical symmetrical NACA 0021 and its derived cambered airfoil,
characterized by a curved chord, having a chord radius equal to rotor
external circumference.
The effects of blade chord curvature on angle of attack, blade
tangential and normal forces are first investigated and then the
overall rotor torque and power are analyzed as a function of blade
azimuthal position, achieving a numerical quantification of the
influence of blade camber on overall rotor performance.", keywords = "VAWT, NACA 0021, DU 06-W-200, cambered
airfoil", volume = "6", number = "1", pages = "144-10", }