Investigation of flow field and torque coefficient of Darrieus wind turbine with respect to pitch angle variations and tip speed ratios

Authors

Abstract

The Darrieus lift-based VAWT has been considered by many scientists due to the simplicity of design and independence to the wind direction. Due to increasing angle of attack at low tip speed ratios, the straight-bladed Darrieus wind turbines have the inherent problem of self-starting inability and have less power coefficient as compared to the horizontal axis wind turbines. In this study, has been showed that use of the variable pitch angle turbines is a suitable solution to overcome the self‌-starting problem and increasing the output power of Darrieus wind turbine. So, the effect of variable blade pitch angle mechanism with different amplitudes on output torque, flow field around the rotor and self-starting of Darrieus wind turbine has been investigated. Also, unsteady two-dimensional simulation is conducted using computational fluid dynamics with SST kω turbulence model and moving mesh technique is used for simulation of the rotating rotor. The numerical investigation shows that variable pitch mechanism decreases the angle of attack and makes the turbine have a chance to produce more torque at different azimuthal angles. Investigation of the flow around the blade also shows that the use of variable pitch blades increases the pressure difference between the low and high pressure of around the blade and delays stall. So, the Darrieus turbine with variable pitch angle in comparison with zero fixed pitch angle has the ability to produce more power at the middle and lower tip speeds ratios.

Keywords

Main Subjects

References

[1] Paraschivoiu I, Trifu O, Saeed F (2009) H-Darrieus wind turbine with blade pitch control. Int J Rot Mach 2009:1-7.
[2] Kiwata T, Yamada T, Kita T, Takata  S, Komatsu  N, Kimura S (2010) Performance of a vertical axis wind turbine with variable-pitch straight blades utilizing a linkage mechanism. J Environment Eng 5(1): 213-225.
[3] ArabGolarche A, Moghiman M, Javadi MalAbad  SM (2015) Numerical simulation of Darrieus wind turbine using interaction. Modarres Mech Eng 15(12): 143-152. (in Persian)
[4] Firdaus R, Kiwata T, Kono T, Nagao K (2015) Numerical and experimental studies of a small vertical-axis wind turbine with variable-pitch straight blades. J Fluid Sci  Tech 10(1): 11-21.
[5] Zhang LX, Liang YB, Liu XH, Guo J (2014) Effect of blade pitch angle on aerodynamic performance of straight-bladed vertical axis wind turbine. J  Central South University 21: 1417-1427.
[6] Bhutta MMA, Hayat N, Farooq AU, Ali Z, Jamil  SR, Hussain Z (2012) Vertical axis wind turbine–A review of various configurations and design techniques. Renew Sust Energ Rev 16(4): 1926-1939.
[7] Elkhoury M, Kiwata T, Aoun E (2015) Experimental and numerical investigation of a three-dimensional vertical-axis wind turbine with variable-pitch. J Wind Eng Ind Aerodyn 139: 111-123.
[8] ArabGolarche A, Moghiman M, Javadi MalAbad SM (2015) Investigation of effective parameters on darrieus wind turbine efficiency with aerodynamics models. Modarres Mech Eng 15(5): 295-301. (in Persian)
[9] Wang S, Ingham DB, Ma L, Pourkashanian M, Tao Z (2010) Numerical investigations on dynamic stall of low Reynolds number flow around oscillating airfoils. Comput  Fluids 39(9): 1529-1541.
[10] Dominy R, Lunt P, Bickerdyke A, Dominy J (2007) Self-starting capability of a Darrieus turbine. Proceedings of the Institution of Mechanical Engineers, Part A: J Pow Energ 221(1): 111-120.
[11] Nobile R, Vahdati M, Barlow J, Mewburn-Crook A (2011) Dynamic stall for a vertical axis wind turbine in a two-dimensional study. World Renew Energ Congr 4225-4232.
[12] Qin N, Howell R, Durrani N, Hamada K, Smith T (2011) Unsteady flow simulation and dynamic stall behaviour of vertical axis wind turbine blades. Wind Eng 35(4): 511-528.
[13] Howell R, Qin N, Edwards J, Durrani N (2010)  Wind tunnel and numerical study of a small vertical axis wind turbine. Renew Energ 35(2): 412-422.
[14] Hill N, Dominy R, Ingram G, Dominy J (2009)  Darrieus turbines: the physics of self-starting  Proceedings of the Institution of Mechanical Engineers, Part A: J Pow Energ 223(1): 21-29.
[15] Islam M, Ting DS, Fartaj A (2007) Desirable airfoil features for smaller-capacity straight-bladed VAWT. Wind Eng 31(3): 165-196.
[16] Kirke BK (1998) Evaluation of self-starting vertical axis wind turbines for stand-alone applications (Doc diss , GRIFFITH UNIVERSITY GOLD COAST).
[17] Tao WYYCZ (2006) Numerical investigation of dynamic stall vortex movement of different-thickness airfoils. J Beij Un Aero Astron 2, 006.
[18] Beri H, Yao Y (2011) Effect of camber airfoil on self starting of vertical axis wind turbine. J Environ Sci Technol 4(3): 302-312.
[19] Paraschivoiu I (2002) Wind turbine design: with emphasis on Darrieus concept. Presses inter Polytechnique.
[20] Amet E, MaÃŽtre T, Pellone C, Achard JL (2009)  2D numerical simulations of blade-vortex interaction in a darrieus turbine. J fluids Eng 131(11): 103-113.
[21] Dyachuk E, Rossande M, Goude A, Bernhoff H  (2015) Measurements of the aerodynamic normal forces on a 12-kW straight-bladed vertical axis wind turbine. Energ 8(8): 8482-8496.
[22] Bos R (2012) Self-starting of a small urban Darrieus rotor. Delft University of Technology.
[23] Xisto CM, Páscoa JC, Leger JA, Trancossi M  (2014) Wind energy production using an optimized variable pitch vertical axis rotor.  ASME 2014 International Mechanical Engineering Congress and Exposition 1: V001T01A007-V001T01A007.
[24] Castelli MR, Englaro A , Benini E (2011) The Darrieus wind turbine: Proposal for a new performance prediction model based on CFD. Energ 36(8): 4919-4934.
[25] Mohamed MH, Ali AM, Hafiz AA (2015) CFD analysis for H-rotor Darrieus turbine as a low speed wind energy converter. Eng Sci  Tech 18(1): 1-13.
[26] Nobile R, Vahdati  M, Barlow  JF, Mewburn-Crook A (2014) Unsteady flow simulation of a vertical axis augmented wind turbine: a two-dimensional study. J Wind Eng  Ind Aerodyn 125: 168-179.
[27] Sun X, Wang Y, An Q, Cao Y, Wu G, Huang D (2014) Aerodynamic performance and characteristic of vortex structures for Darrieus wind turbine. I. Numerical method and aerodynamic performance.  J  Renew Sus Energ 6(4): 043134.
[28] Armstrong S, Fiedler  A, Tullis S (2012) Flow separation on a high Reynolds number, high solidity  vertical axis wind turbine with straight and canted blades and canted blades with fences. Renew Energ 41: 13-22.
Journal of Solid and Fluid Mechanics
Volume 6, Issue 4
January and February 2016
Pages 173-191

Files

Share

How to cite

Statistics