Energy Balance Analysis and Turbulence Profile of a Darrieus-typeVertical Axis Wind Turbine
Main Article Content
Abstract
Vertical axis wind turbines (VAWTs) extract energy through reduction of the kinetic and turbulent kinetic energies, and the vertical momentum flux. Detailed turbulence profiling and energy balance analysis were attempted through direct turbulence quantification using the Eddy Covariance method. A high-frequency sonic anemometer was employed to measure flow and turbulence upwind and downwind of a Darrieus-type VAWT at different positions that cover the entire windswept area. The data was processed and analysed using a custom Matlab script. Energy balance analysis showed that there was a significant drop in kinetic energy before and after the VAWT (72% to 42%) but a small increase in turbulent kinetic energy (28% to 31%). The results also showed that the rotational direction of VAWT contributed to a higher value of longitudinal turbulence at the windward edge of the VAWT. The VAWT affected the flow field upwind by generating reverse flows. The largest vertical momentum flux transfer occurred downwind of the windward side of the VAWT. Spectral analysis shows that the VAWT produced smaller but faster momentum flux vortices due to the rotating rotors in the 1 Hz to 5 Hz range. This data and results have important applications to accurately model complex flows around VAWTs.
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
References
Balduzzi, F. et al. (2012). Feasibility analysis of a Darrieus vertical-axis wind turbine installation in the rooftop of a building. Appl. Energy, 97, 921–929, https://doi.org/10.1016/j.apenergy.2011.12.008.
Mertens, S. (2002). Wind energy in urban areas: Concentrator effects for wind turbines close to buildings. Refocus, 3(2), 22–24, https://doi.org/10.1016/S1471-0846(02)80023-3.
Didane, D. H. et al. (2018). Performance evaluation of a novel vertical axis wind turbine with coaxial contra-rotating concept. Renew. Energ., 115, 353-361, https://doi.org/10.1016/j.renene.2017.08.070.
Aravind, C. V. et al. (2012). A novel magnetic levitation assisted vertical axis wind turbine: Design procedure and analysis. Paper presented at the 2012 IEEE 8th International Colloquium on Signal Processing and its Applications, 23–25 March, Melaka, Malaysia.
Aravind, C. et al. (2014). Design analysis of MAGLEV-VAWT with modified magnetic circuit generator. Paper presented at the IEEE 2nd International Conference on Electrical Energy Systems (ICEES), 7–9 January, Chennai, India.
Khan, S. et al. (2013). Performance analysis of 20 pole 1.5 kW three phase permanent magnet synchronous generator for low speed vertical axis wind turbine. Energy Power Eng., 5(4B), 423–428, https://doi.org/10.4236/epe.2013.54B082.
Teow, W. W. & Aravind, C. V. (2018). Magnetic geared radial axis vertical wind turbine for low velocity regimes. MATEC Web Conf., 152, 03007, https://doi.org/10.1051/matecconf/201815203007.
Khan, M. S. A. et al. (2016). Feasibility study of a novel 6V supercapacitator based energy harvesting circuit integrated with vertical axis wind turbine for low wind areas. Int. J. Renew. Energy Res., 6(3), 1167–1177.
Tabrizi, A. B. et al. (2015). Rooftop wind monitoring campaigns for small wind turbine applications: Effect of sampling rate and averaging period. Renew. Energy, 77, 320–330, https://doi.org/10.1016/j.renene.2014.12.037.
Islam, M. R., Saidur, R. & Rahim, N. A. (2011). Assessment of wind energy potentiality at Kudat and Labuan, Malaysia using Weibull distribution function. Energy, 36(2), 985–992, https://doi.org/10.1016/j.energy.2010.12.011
Nor, K. M., Shaaban, M. & Rahman, H. A. (2014). Feasibility assessment of wind energy resources in Malaysia based on NWP models. Renew. Energy, 62(2014), 147–154, https://doi.org/10.1016/j.renene.2013.07.001
Dabiri, J. O. (2011). Potential order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind turbine arrays. J. Renew. Sustain. Energy, 3(4), 1–12, https://doi.org/10.1063/1.3608170.
Kinzel, M., Mulligan, Q. & Dabiri, J. O. (2013). Energy exchange in an array of vertical axis wind turbines. J. Turbul., 14(6), 38–39, https://doi.org/10.1080/14685248.2013.825725.
Anderson, D. C. et al. (2008). Rooftop wind resource assessment using a ThreeDimension Ultrasonic Anemometer. Paper presented at the 7th World Wind Energy Conference (WWEC2008), Kingston, Canada, 24–26 June.
Vermeer, L. J., Sorensen, J. N. & Crespo, A. (2003). Wind turbine wake aerodynamics. Prog. Aerosp. Sci., 39(6–7), 467–510, https://doi.org/10.1016/ S0376-0421(03)00078-2.
Roth, M. (2000). Review of atmospheric turbulence over cities. Quart. J. Roy. Meteor. Soc., 126(564), 941–990, https://doi.org/10.1002/qj.49712656409.
Tabrizi, A. B. et al. (2015). Extent to which international wind turbine design standard, IEC61400-2 is valid for a rooftop wind installation. J. Wind. Eng. Ind. Aerod., 139, 50–61, https://doi.org/10.1016/j.jweia.2015.01.006.
Wharton, S. & Lundquist, J. K. (2012). Atmospheric stability affects wind turbine power collection. Environ. Res. Lett., 7(1), 014005, https://doi.org/10.1088/1748-9326/7/1/014005.
H'ng, Y. et al. (2014). Pilot study on indoor flows and turbulence statistics of a vertical axis wind turbine. Mech. Eng. Res., 4(1), 63–78, https://doi.org/10.5539/mer.v4n1p63.
Yang, Z. F., Sarkar, P. & Hu, H. (2012). Visualization of the tip vortices in a wind turbine wake. J. Vis.-Jap., 15(1), 39–44, https://doi.org/10.1007/s12650-011-0112-z.
Wahab, A. A. & Tong, C. W. (1999). Utilizing the energy from induced wind produce by highway vehicle motions. Paper presented at the World Renewable Energy Congress 99, Kuala Lumpur, Malaysia, 8–11 June.
Ragheb, M. & Ragheb, A. M. (2011). Wind turbines theory: The Betz Equation and optimal rotor tip speed ratio. In Carriveau, R. (Ed.). Fundamental and advanced topics in wind power. Rijeka: InTech, 19.
Vickers, D. & Mahrt, L. (1997). Quality control and flux sampling problems for tower and aircraft data. J. Atmos. Ocean. Technol., 14(3), 512–526, https://doi.org/10.1175/1520-0426(1997)014<0512:QCAFSP>2.0.CO;2.
Yusup, Y. & Anis, S. I. (2016). Similarity theory and nocturnal locally scaled turbulence variances in the tropical urban roughness sublayer. Atmos. Pollut. Res.,7(3), 454–468, https://doi.org/10.1016/j.apr.2015.11.002.
Yusup, Y. & Lim, J. F. (2014). Turbulence variances in the convective urban roughness sublayer: An application of similarity theory using local scales. Meteorol. Appl., 21(2), 149–160, https://doi.org/10.1002/met.1316.
Stull, R. B. (1988). An introduction to boundary layer meteorology. Boston: Kluwer Academic Publishers.
D'Alessandro, V. et al. (2010). Unsteady aerodynamics of a Savonius wind rotor: A new computational approach for the simulation of energy performance. Energy, 35(8), 3349–3363, https://doi.org/10.1016/j.energy.2010.04.021.
Tescione, G., Simão Ferreira, C. J. & van Bussel, G. J. W. (2016). Analysis of a free vortex wake model for the study of the rotor and near wake flow of a vertical axis wind turbine. Renew. Energy, 87(1), 552–563, https://doi.org/10.1016/j. renene.2015.10.002.
Wahab, A. A. & Chong, W. T. (2003). Development of an indoor testing facility for low wind speed wind turbine research activities. Paper presented at the Proceedings of the 2nd Regional Conference on Energy Technology Towards a Clean Environment, Phuket, Thailand, 12–14 February.
Troldborg, N., Sorensen, J. N. & Mikkelsen, R. (2007). Actuator line simulation of wake of wind turbine operating in turbulent inflow. J. Phys. Conf. Ser., 75(1), 12063–12063, https://doi.org/10.1088/1742-6596/75/1/012063.
Hansen, K. S. et al. (2012). The impact of turbulence intensity and atmospheric stability on power deficits due to wind turbine wakes at Horns Rev wind farm. Wind Energy, 15(1), 183–196, https://doi.org/10.1002/we.512.
Breton, S. P. et al. (2014). Comparative CFD study of the effect of the presence of downstream turbines on upstream ones using a rotational speed control system. J. Phys. Conf. Ser., 555(1), https://doi.org/10.1088/1742-6596/555/1/012014.
Hasager, C. B. et al. (2013). Wind farm wake: The Horns Rev photo case. Energies, 6(2), 696–716, https://doi.org/10.3390/en6020696.
Hunt, J. C. R. & Morrison, J. F. (2000). Eddy structure in turbulent boundary layers. Eur. J. Mech. B-Fluid., 19(5), 673–694, https://doi.org/10.1016/S0997-7546(00)00129-1.
Tummala, A. et al. (2016). A review on small scale wind turbines. Renew. Sust. Energ. Rev., 56,1351–1371, https://doi.org/10.1016/j.rser.2015.12.027.
Peng, H. Y. & Lam, H. F. (2016). Turbulence effects on the wake characteristics and aerodynamic performance of a straight-bladed vertical axis wind turbine by wind tunnel tests and large eddy simulations. Energy, 109, 557–568, https://doi.org/10.1016/j.energy.2016.04.100
Kinzel, M., Araya, D. B. & Dabiri, J. O. (2015). Turbulence in vertical axis wind turbine canopies. Phys. Fluids, 27(11), 115102, https://doi.org/10.1063/1.4935111.
Jha, P. et al. (2015). Unraveling the mysteries of turbulence transport in a wind farm. Energies, 8(7), 6468, https://doi.org/10.3390/en8076468.
Dörenkämper, M. et al. (2015). The impact of stable atmospheric boundary layers on wind-turbine wakes within offshore wind farms. J. Wind. Eng. Ind. Aerod., 144,146–153, https://doi.org/10.1016/j.jweia.2014.12.011.
Wu, Y. T. & Porte-Agel, F. (2012). Atmospheric turbulence effects on windturbine wakes: an LES study. Energies, 5(12), 5340–5362, https://doi.org/10.3390/en5125340.