In this paper, Blade Element Momentum theory (BEM) is used to design a HAWT blade for a 200 kW wind turbine. The airfoil is Risø, produced by RISØ National Laboratory, Denmark, for a class of 200KW wind turbines. Desirable properties of this airfoil are related to enhancement of aerodynamic and structure interactions. The purpose of this study is to find a simpler linear modification to the shape of blades. Design parameters considered here are wind tip speed ratio, nominal wind speed and diameter of rotor. BEM is used for obtaining maximum lift to drag ratio for each elemental constitution of the blade. Obtaining chord and twist distribution at assumed tip speed ratio of blade, the aerodynamic shape of the blade in every part is specified which correspond to maximum accessible power coefficient. In order to simplify manufacturing of the blades, a linear approximation is employed for both chord and twist distribution. The design parameters are trust coefficient, power coefficient, angle of attack, angle of relative wind, drag and lift coefficients, axial and angular induction factors. The blade design distributions are presented against rotor radius for BEM results and also compared with the linear approximation.
Keywords. Horizontal axis wind turbine (HAWT); Aerodynamic performance; BEM theory; Blade optimization; Pitch control system
References
Wenzhi L, Fuhai ZH, Jianxin W, and Changzeng L, “3D Modeling Methods of Aerodynamic Shape for Large-Scale Wind Turbine Blades”, International Conference on Information Technology and Computer Science, 2009, IEEE Conference; DOI 10.1109/ITCS.2009.10; P. 7-10.
Johansen J, Madsen HA, Gaunaa M, and Bak C, “Design of a Wind Turbine Rotor for Maximum Aerodynamic Efficiency”, Wind Energy. 12, 261–73 (2009).
Schreck SJ, and Robinson MC, “Horizontal Axis Wind Turbine Blade Aerodynamics in Experiments and Modeling”, IEEE Transactions Energy convers. 22 (1), 61-70 (March 2007).
Dong L, Liao M, Li Y, Song X, and Xu K, “Study on Aerodynamic Design of Horizontal Axis Wind Turbine Generator System”, International Conference on Energy and Environment Technology, 2009, IEEE Conference; DOI 10.1109/ICEET.2009.208; p. 841-4.
Madsen, H.A. “A CFD analysis of the actuator disc flow compared with momentum theory results”, Proceedings of the 10th Symposium on Aerodynamics of Wind Turbines, IEA Joint Action, Edinburgh, 1996, 109–124.
Madsen HA, and Rasmussen F, “A Near Wake Model for Trailing Vorticity Compared with the Blade Element Momentum Theory”, Wind Energy. 7, 325–41 (2004).
Griffiths, R.T. “The effect of airfoil characteristics on windmill performance”, Aeronaut J. 81(7), 322-6 (1977).
Mirhosseini, M, Sharifi, F, Sedaghat, A., “Assessing the wind energy potential locations in province of Semnan in Iran”, J. Renew Sustain Energy Rev. 15, 449–59 (2011).
Manwell, J. “Wind energy explained: theory, design and application”, John Wiley & Sons Inc, 83-138 (2002).
How to cite this article
Mirhosseini, M., Sedaghat, A. and Alemrajabi, A. (2011). 'Aerodynamic Modeling of Wind Turbine Blades and Linear Approximations'. SET Proceedings, 10, pp. 1-6. https://doi.org/10.65582/set.2011.298