Experiments in Fluids

, 55:1637 | Cite as

Influence of turbulence on the drag of solid discs and turbine simulators in a water current

  • Tom BlackmoreEmail author
  • William M. J. Batten
  • Gerald U. Műller
  • AbuBakr S. Bahaj
Research Article


Laboratory experiments have been used to investigate the effects of turbulence on the drag of both solid discs and porous disc turbine simulators. These discs were introduced to turbulent flows, in a gravity-fed water flume, with various levels of turbulence intensity and integral length scales. The turbulence was generated using three different grid configurations, which produced intensities and scales comparable with previous wind tunnel studies. The drag measurements were taken with discs of two different diameters and porosities with and without the upstream grids. The experimental results have demonstrated that the drag coefficients, of all the discs tested, are significantly dependent on both the turbulence intensity and integral length scale. For small integral length scales, relative to the disc, the drag coefficients converged for turbulence intensities greater than 13 %, with an increase of around 20 % in drag coefficient over the low-intensity case. Experiments with turbulence intensities of 10 % demonstrated minimum drag coefficients when the integral length scale-to-disc diameter ratio was around 50 %. Significant variations in the drag coefficient of circular bluff bodies are therefore expected when operating in turbulent flows with different characteristics.


Drag Force Drag Coefficient Turbulence Intensity Integral Length Scale Porous Disc 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under Grant agreement number 212423.


  1. Bahaj AS, Molland AF, Chaplin JR, Batten WMJ (2007) Power and thrust measurements of marine current turbines under various hydrodynamic flow conditions in a cavitation tunnel and a towing tank. Renew Energy 32(3):407–426CrossRefGoogle Scholar
  2. Bearman PW, Morel T (1983) Effect of free stream turbulence on the flow around bluff bodies. Prog Aerosp Sci 20:97–123CrossRefGoogle Scholar
  3. Cea L, Puertas J, Pena L (2007) Velocity measurements on highly turbulent free surface flow using ADV. Exp Fluids 42:333–348CrossRefGoogle Scholar
  4. Craze DJ (1977) On the near wake behind a circular disc, 6th Australasian hydraulics and fluid mechanics conference, pp 282–286Google Scholar
  5. Comte-bellott G, Corrsin S (1966) The use of a contraction to improve the isotropy of grid-generated turbulence. J Fluid Mech 25(4):657–682CrossRefGoogle Scholar
  6. Espana G, Aubrun A, Loyer P, Devinant P (2012) Wind tunnel study of the wake of meandering downstream of a modelled wind turbine as an effect of large scale turbulent eddies. J Wind Eng Ind Aerodyn 101:24–33CrossRefGoogle Scholar
  7. Knight M (1926) Wind tunnel standardization disk drag, N.A.C.A. Technical note, no. 253Google Scholar
  8. Krogstad PA, Davidson PA (2009) Is grid turbulence Saffman turbulence? J Fluid Mech 642:373CrossRefMathSciNetGoogle Scholar
  9. Massey B, War-Smith J (2008) Mechanics of fluids, 8th edition. Taylor & Fancis, OxonGoogle Scholar
  10. Milne IA, Sharma RN, Flay RGJ, Bickerton S (2010) Characteristics of the onset flow turbulence at a tidal-stream power site, 9th European wave and tidal energy conferenceGoogle Scholar
  11. Mohamed MS, LaRue JC (1990) The decay power lay in grid-generated turbulence. J Fluid Mech 219:195–214CrossRefGoogle Scholar
  12. Myers LE, Bahaj AS (2010) Experimental analysis of the flow field around horizontal axis tidal turbines by use of scale mesh disk rotor simulators. Ocean Eng 37:218-227CrossRefGoogle Scholar
  13. Pope SB (2000) Turbulent flows. Cambridge University Press, CambridgeCrossRefzbMATHGoogle Scholar
  14. Rind E, Castro IP (2012) On the effects of free-stream turbulence on axisymmetric disc wakes. Exp Fluids 53(2):301–318CrossRefGoogle Scholar
  15. Roos FM, Willmarth WW (1971) Some experimental results on sphere and disk drag. AIAA J 9(2):285–291CrossRefGoogle Scholar
  16. Schubauer GB, Dryden HL (1935) The effect of turbulence on the drag of flat plates, NACA Rep. no. 546Google Scholar
  17. Sforza PM, Sheerin P, Smorto M (1981) Three-dimensional wakes of simulated wind turbines. AIAA J 19:1101–1107CrossRefGoogle Scholar
  18. Taylor GI (1963) In: Batchelor GK (ed) The scientific papers of Sir Geoffrey Ingram Taylor. Cambridge University Press, CambridgeGoogle Scholar
  19. Thomson J, Polagye B, Durgesh V, Richmond MC (2012) Measurements of turbulence at two tidal energy sites in Puget Sound, WA. IEEE J Ocean Eng 37:363–374CrossRefGoogle Scholar
  20. Wyngaard JC (1992) Atmospheric turbulence. Annu Rev Fluid Mech 24:205–233CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Tom Blackmore
    • 1
    Email author
  • William M. J. Batten
    • 1
  • Gerald U. Műller
    • 1
  • AbuBakr S. Bahaj
    • 1
  1. 1.Faculty of Engineering and the EnvironmentUniversity of SouthamptonSouthamptonUK

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