Effect of Dynamic Stall, Finite Aspect Ratio and Streamtube Expansion on VAWT Performance Prediction using the BE-M Model

Authors: M. Raciti Castelli, A. Fedrigo, E. Benini

Abstract:

A multiple-option analytical model for the evaluation of the energy performance and distribution of aerodynamic forces acting on a vertical-axis Darrieus wind turbine depending on both rotor architecture and operating conditions is presented. For this purpose, a numerical algorithm, capable of generating the desired rotor conformation depending on design geometric parameters, is coupled to a Single/Double-Disk Multiple-Streamtube Blade Element – Momentum code. Both single and double-disk configurations are analyzed and model predictions are compared to literature experimental data in order to test the capability of the code for predicting rotor performance. Effective airfoil characteristics based on local blade Reynolds number are obtained through interpolation of literature low-Reynolds airfoil databases. Some corrections are introduced inside the original model with the aim of simulating also the effects of blade dynamic stall, rotor streamtube expansion and blade finite aspect ratio, for which a new empirical relationship to better fit the experimental data is proposed. In order to predict also open field rotor operation, a freestream wind shear profile is implemented, reproducing the effect of atmospheric boundary layer.

Keywords: Wind turbine, BE-M, dynamic stall, streamtube expansion, airfoil finite aspect ratio

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1070137

References:

[1] T. Burton and D. Sharpe, N. Jenkins and E. Bossanyi, E., Wind Energy Handbook, John Wiley & Sons, Ltd, Baffins Lane, Chichester - West Sussex, PO19 1UD, England, 2001, p. 61.
[2] H. Glauert, Airplane Propellers, Aerodynamic Theory, Dover Publication Inc, New York, 1963, Vol. 4, Division L, 169-360.
[3] R. J. Templin, Aerodynamic Theory for the NRC Vertical-Axis Wind Turbine, NRC of Canada TR LTR-LA-160, 1974.
[4] P. C. Klimas, "Darrieus Rotor Aerodynamics", Sandia National Laboratories, Advanced Energy Projects Division 4715, Albuquerque, NM 87185.
[5] M. C. Claessens, The Design and Testing of Airfoils for Application in Small Vertical Axis Wind Turbines, Master of Science Thesis, Faculty of Aerospace Engineering, Delft University of Technology, November 9, 2006.
[6] J. H. Strickland, "The Darrieus Turbine: A Performance Prediction Model Using Multiple Streamtube", Sandia Report, SAND75-0431.
[7] S. Read and D. J. Sharpe, "An Extended Multiple Streamtube Theory for Vertical Axis Wind Turbines", Department of M.A.P. Engineering Report, Kingston Polytechnic, Kingston upon Times, United Kingdom, 1980.
[8] I. Paraschivoiu, "Double-Multiple Streamtube Model for Darrieus Wind Turbines", NASA Conference Publication 2185, May 1981.
[9] I. Paraschivoiu and F. Delclaux, "Double Multiple Streamtube Model with Recent Improvements", Journal of Energy, 7(3), 1983, pp. 250- 255.
[10] H. Mc Coy and J. L. Loth, "Up- and Downwind Rotor Half Interference Model for VAWT", AIAA 2nd Terrestrial Energy Systems Conference, Colorado Springs, CO, December 1-3, 1981.
[11] H. Mc Coy and J. L. Loth, "Optimization of Darrieus Turbines with an Upwind and Downwind Momentum Model", Journal of Energy, 7(4), 1983, pp. 313-318.
[12] R. E. Sheldal and C. Klimas, "Aerodynamic Characteristics of Seven Symmetrical Airfoil Sections Through 180-Degree Angle of Attack for Use in Aerodynamic Analysis of Vertical Axis Wind Turbines", Sandia National Laboratories, Energy Report, SAND80-2114, March 1981.
[13] M. H. Worstell, "Aerodynamic Performance of the 17 Meter Diameter Darrieus Wind Turbine", Sandia Report, SAND78-1737.
[14] M. H. Worstell, "Aerodynamic Performance of the 17-M-Diameter Darrieus Wind Turbine in the Three-Bladed Configuration: An Addendum", Sandia Report, SAND79-1753.
[15] M. O. L. Hansen, Aerodynamics of Wind Turbines, Earthscan, UK and USA, Second Edition, 2008, p. 30.
[16] H. Glauert, "A General Theory of the Autogyro", ARCR R&M, No. 1111, 1926.
[17] K. G. Pierce, Wind Turbine Load Prediction using the Beddoes- Leishman Model for Unsteady Aerodynamics and Dynamic Stall, Master of Science Thesis, Department of Mechanical Engineering, The University of Utah, August 1996.
[18] C. Masson, C. Leclerc, and I. Paraschivoiu, "Appropriate Dynamic-Stall Models for Performance Predictions of VAWTs with NLF Blades", International Journal of Rotating Machinery, 1998, Vol. 4, No. 2, pp. 129-139.
[19] R. E. Gormont, "An Analytical Model of Unsteady Aerodynamics and Radial Flow for Application to Helicopter Rotors", U.S. Army Air Mobility Research and Development Laboratory Technical Report, pp. 72-67, 1973.
[20] J. H. Strickland, B. T. Webster and T. Nguyen, "A Vortex Model of the Darrieus Turbine: an Analytical and Experimental Study", Sandia report, SAND79-7058.
[21] B. Massé, "Description de deux programmes d-ordinateur pour le calcul des performance et des charges aérodynamiques pour les éoliennes ├á axe vertical", IREQ-2379, 1981.
[22] D. E. Berg, "An Improved Double-Multiple Streamtube Model for the Darrieus-Type Vertical Axis Wind Turbine", Sixth Biennal Wind Energy Conference and Workshop, pp. 231-233.
[23] L. Battisti, A. Brighenti and L. Zanne, "Analisi dell-effetto della scelta dell-architettura palare sulle prestazioni di turbine eoliche ad asse verticale" (in Italian), 64┬░ Convegno ATI, L-Aquila, Italia, 2009.
[24] S. Read and D. J. Sharpe, "An Extended Multiple Streamtube Theory for Vertical Axis Wind Turbines", 2nd BWEA Workshop, April 1980.
[25] I. H. Abbot and A. E. Von Doenhoff, Theory of Wing Sections, Dover Edition, 1959.
[26] L. A. Viterna and R. D. Corrigan, "Fixed Pitch Rotor Performance of Large Horizontal Axis Wind Turbines", DOE/NASA Workshop on Large Horizontal Axis Wind Turbines, 28-30 July 1981, Cleveland, OH.