Numerical and Experimental Efficiency Evaluation of a Counter-Rotating Vertical Axis Wind Turbine

I. Malael, V. Dragan

Abstract


This paper investigates the concept of a concentric counter-rotating vertical axis wind turbine (VAWT), consisting of a two stage vertical H-type turbine with three blades on each stage. The model has an inner and an outer stage, rotating in opposition to each other. Both numerical and experimental tests have been performed in order to validate this new concept. Numerical analysis is based on the use of 2.5-dimensional, unsteady simulations using a DOF type of analysis which allows for the two stages to self-adjust their rotation speed. Sliding mesh conformal interfaces are defined between these subdomains to minimize numerical artifacts such as artificial relations or entropy changes. Fully turbulent URANS were carried out in Ansys Fluent software. One key outcome was the momentum coefficient for each stage at different tip wind speed values. Another, more qualitative, outcome is the analysis of vortex shedding, impingement and overall interaction between the stages at different positions and scenarios. Ultimately, the numerical results have been validated using a scaled experimental device which was analyzed in the wind tunnel at different free stream speeds.


Keywords


CFD; counter rotating; wind tunnel; wind turbine

Full Text:

PDF

References


P. A. Costa Rocha, J. W.Carneiro de Araujo, R. J. Pontes Lima, M. E.Vieira da Silva, D. Albiero, C. F. de Andrade, F. O. M. Carneiro, “The effects of blade pitch angle on the performance of small-scale wind turbine in urban environments”, Energy, Vol. 148, pp. 169-178, 2018

T. Wenlong, M. Zhaoyong, B. Zhanga, Y. Li, “Shape optimization of a Savonius wind rotor with different convex and concave sides”, Renewable Energy, Vol. 117, pp. 287-299, 2018

R. Gupta, A. Biswas, K. K. Sharma, “Comparative study of a three-bucket Savonius rotor with a combined three-bucket Savonius–three-bladed Darrieus rotor”, Renewable Energy, Vol. 33, No. 9, pp. 1974-1981, 2008

J. Gavalda, J. Massons, F. Diaz, “Experimental study on a self-adapting Darrieus—Savonius wind machine”, Solar & Wind Technology, Vol. 7, No. 4, pp. 457-461, 1990

A. Ghosh, A. Biswas, K. K. Sharma, R. Gupta, “Computational analysis of flow physics of a combined three bladed Darrieus Savonius wind rotor”, Journal of the Energy Institute, Vol. 88, No. 4, pp. 425-437, 2015

K. Sahim, D. Santoso, D. Puspitasari, “Investigations on the Effect of Radius Rotor in Combined Darrieus-Savonius Wind Turbine”, International Journal of Rotating Machinery, Vol. 2018, 2018

Y. Kyozuka, “An Experimental Study on the Darrieus-Savonius Turbine for the Tidal Current Power Generation”, Journal of Fluid Science and Technology, Vol. 3, No. 3, pp. 439-449, 2008

X. Liang, S. Fu, B. Ou, C. Wu, C. Y. H. Chao, K. Pi, “A computational study of the effects of the radius ratio and attachment angle on the performance of a Darrieus-Savonius combined wind turbine”, Renewable Energy, Vol. 113, pp. 329-334, 2017

I. Paraschivoiu, O. Trifu, F. Saeed. “H-Darrieus wind turbine with blade pitch control”, International Journal of Rotating Machinery, Vol. 2009, 2009

D. Horia, A. Dumitrache, F. Frunzulica, A. Pal, V. Turbatu, “TORNADO concept and realisation of a rotor for small VAWTs”, NCAS Bulletin, Vol. 5, No. 3, pp. 69–75, 2013

M. J. Werle, W. M. Presz, “Ducted wind/water turbines and propellers revisited”, Journal of Propulsion and Power, Vol. 24, No. 5, pp. 1146-1150, 2008

S. Ivanell, J. N. Sorensen, D. Henningson, “Numerical computations of wind turbine wakes”, in: Wind Energy, Springer, pp. 259-263, 2007

D. Hartwanger, A. Horvat, “3D modelling of a wind turbine using CFD”, NAFEMS Conference, Cheltenham, UK, June 10-11, 2008

M. R. Castelli, A. Englaro, E. Benini, “The Darrieus wind turbine: Proposal for a new performance prediction model based on CFD”, Energy, Vol. 36, No.8, pp. 4919-4934, 2011

F. Balduzzi, A. Bianchini, R. Maleci, G. Ferrara, L. Ferrari, “Critical No.s in the CFD simulation of Darrieus wind turbines”, Renewable Energy, Vol. 85, pp. 419-435, 2016

W. A. Timmer, R. P. J. O. M. Van Rooij, “Summary of the Delft University wind turbine dedicated airfoils”, Journal of Solar Energy Engineering, Vol. 125, No. 4, pp. 488-496, 2003

I. Malael, V. Dragan, G. Vizitiu, “The vertical axis wind turbine efficiency evaluation by using the CFD methods”, Applied Mechanics and Materials, Vol. 772, pp. 90-95, 2015

H. Dumitrescu, V. Cardos, I. Malael, “The physics of starting process for vertical axis wind turbines”, in: CFD for Wind and Tidal Offshore Turbines, pp. 69-81, Springer, 2015

G. Naccache, M. Paraschivoiu, “Parametric study of the dual vertical axis wind turbine using CFD”, Journal of Wind Engineering and Industrial Aerodynamics, Vol. 172, pp. 244-255, 2018

M. Dranca, M. Chirca, V. Zaharia, S. Breban, “Permanent magnet generator for counter-rotating vertical axis micro-wind turbine”, 52nd International Universities Power Engineering Conference, Heraklion, Greece, August 28-31, 2017

R. Howell, N. Qin, J. Edwards, N. Durrani, “Wind tunnel and numerical study of a small vertical axis wind turbine”, Renewable energy, Vol. 35, No. 2, pp. 412-422, 2010




eISSN: 1792-8036     pISSN: 2241-4487