Hostname: page-component-745bb68f8f-cphqk Total loading time: 0 Render date: 2025-02-01T16:49:56.707Z Has data issue: false hasContentIssue false
  • English
  • Français

Two-scale dynamics of flow past a partial cross-stream array of tidal turbines

Published online by Cambridge University Press:  30 July 2013

Takafumi Nishino  and
Richard H. J. Willden
Takafumi Nishino*
Affiliation:
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK
Richard H. J. Willden
Affiliation:
Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK
*
†Email address for correspondence: nishino25uk@gmail.com
Get access Rights & Permissions [Opens in a new window]

Abstract

The characteristics of flow past a partial cross-stream array of (idealized) tidal turbines are investigated both analytically and computationally to understand the mechanisms that determine the limiting performance of partial tidal fences. A two-scale analytical partial tidal fence model reported earlier is further extended by better accounting for the effect of array-scale flow expansion on device-scale dynamics, so that the new model is applicable to short fences (consisting of a small number of devices) as well as to long fences. The new model explains theoretically general trends of the limiting performance of partial tidal fences. The new model is then compared to three-dimensional Reynolds-averaged Navier–Stokes (RANS) computations of flow past an array of various numbers (up to 40) of actuator disks. On the whole, the analytical model agrees well with the RANS computations, suggesting that the two-scale dynamics described in the analytical model predominantly determines the fence performance in the RANS computations as well. The comparison also suggests that the limiting performance of short partial fences depends on how much of device far-wake mixing takes place within the array near-wake region. This factor, however, depends on the structures of the wake and therefore on the type/design of devices to be arrayed.

JFM classification

Waves/Free-surface Flows: Channel flow Geophysical and Geological Flows: Coastal engineering Geophysical and Geological Flows: Shallow water flows
Type
Papers
Information
Journal of Fluid Mechanics , Volume 730 , 10 September 2013 , pp. 220 - 244
Copyright
©2013 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Corten, G. P. 2000 Heat generation by a wind turbine. In Proceedings of 14th IEA Symposium on the Aerodynamics of Wind Turbines, NREL, CO, USA.Google Scholar
Garrett, C. & Cummins, P. 2005 The power potential of tidal currents in channels. Proc. R. Soc. A 461, 2563–2572.Google Scholar
Garrett, C. & Cummins, P. 2007 The efficiency of a turbine in a tidal channel. J. Fluid Mech. 588, 243–251.Google Scholar
Houlsby, G. T., Draper, S. & Oldfield, M. L. G. 2008 Application of linear momentum actuator disc theory to open channel flow. Tech. Rep. OUEL 2296/08, Department of Engineering Science, University of Oxford.Google Scholar
Launder, B. E. & Spalding, D. B. 1974 The numerical computation of turbulent flows. Comput. Meth. Appl. Mech. Engng 3, 269–289.Google Scholar
Nishino, T. & Willden, R. H. J. 2012a Effects of 3-D channel blockage and turbulent wake mixing on the limit of power extraction by tidal turbines. Intl J. Heat Fluid Flow 37, 123–135.Google Scholar
Nishino, T. & Willden, R. H. J. 2012b The efficiency of an array of tidal turbines partially blocking a wide channel. J. Fluid Mech. 708, 596–606.Google Scholar
Nishino, T. & Willden, R. H. J. 2012c Low-order modelling of blade-induced turbulence for RANS actuator disk computations of wind and tidal turbines. In Proceedings of EUROMECH Colloquium 528: Wind Energy and the Impact of Turbulence on the Conversion Process, Oldenburg, Germany.Google Scholar
Nishino, T. & Willden, R. H. J. 2013 The efficiency of tidal fences: a brief review and further discussion on the effect of wake mixing. In Proceedings of 32nd International Conference on Ocean, Offshore and Arctic Engineering (OMAE2013), Nantes, France.CrossRefGoogle Scholar
Patankar, S. V. 1980 Numerical Heat Transfer and Fluid Flow. Hemisphere.Google Scholar
Rhie, C. M. & Chow, W. L. 1983 Numerical study of the turbulent flow past an airfoil with trailing edge separation. AIAA J. 21, 1525–1532.Google Scholar
Vennell, R. 2010 Tuning turbines in a tidal channel. J. Fluid Mech. 663, 253–267.CrossRefGoogle Scholar
Vennell, R. 2011 Tuning tidal turbines in-concert to maximise farm efficiency. J. Fluid Mech. 671, 587–604.Google Scholar
Vennell, R. 2012 The energetics of large tidal turbine arrays. Renew. Energy 48, 210–219.Google Scholar
Vennell, R. 2013 Exceeding the Betz limit with tidal turbines. Renew. Energy 55, 277–285.Google Scholar
Whelan, J. I., Graham, J. M. R. & Peiró, J. 2009 A free-surface and blockage correction for tidal turbines. J. Fluid Mech. 624, 281–291.Google Scholar