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Coherent Structures in Turbulent Flow over Arrays of Cubical Obstacles

  • Stefano Leonardi
  • Ian Castro
Conference paper
Part of the IUTAM Bookseries book series (IUTAMBOOK, volume 22)

Abstract

The organised motion in turbulent flows over arrays of cubical obstacles has been investigated using direct numerical simulations. Six plan densities have been examined in detail. Relative to a smooth surface, the streamwise extent of the near-wall structures is decreased while their spanwise and wall normal extent is increased. Near the crests’ plane, the inclination of the average structure is larger than that over a smooth wall. The Reynolds stress anisotropy tensor and its invariants show a closer approach to isotropy over the rough wall than over a smooth wall. The mechanism leading to increased isotropy has been explained in the paper through consideration of the Reynolds stress budgets.

Keywords

Direct Numerical Simulation Reynolds Stress Spanwise Direction Turbulent Transport Smooth Wall 
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.

Notes

Acknowledgements

This research was supported in part by the National Science Foundation through TeraGrid resources provided by TACC and in part by the UK Turbulence Consortium during SL’s visits to Southampton.

References

  1. 1.
    I.P. Castro, H. Cheng H., R. Reynolds, Turbulence over urban-type roughness: deductions from wind-tunnel measurements. Bound. Layer Meteorol. 188, 109–131 (2006).Google Scholar
  2. 2.
    H. Cheng, I.P. Castro, Near wall flow over urban-like roughness. Bound. Layer Meteorol. 104, 229–259 (2002).CrossRefGoogle Scholar
  3. 3.
    O. Coceal, A. Dobre, T.G. Thomas, S.E. Belcher, Structure of turbulent flow over regular arrays of cubical roughness J. Fluid Mech, 589, 375–409 (2007).zbMATHCrossRefGoogle Scholar
  4. 4.
    L. Djenidi, R. Elavarasan, R.A. Antonia, The turbulent boundary layer over transverse square cavities. J. Fluid Mech. 395, 271–294 (1999).zbMATHCrossRefGoogle Scholar
  5. 5.
    A.J. Grass, R.J. Stuart, M. Mansour-Thehrani, Common vortical structure of turbulent flows over smooth and rough boundaries. AIAA J. 31, 837–846 (1993).CrossRefGoogle Scholar
  6. 6.
    J.-Y. Hwang, K.-S. Yanga, Numerical study of vortical structures around a wall-mounted cubic obstacle in channel flow Phys. Fluids 16, (2004)Google Scholar
  7. 7.
    S.J. Kline, W.C. Reynolds, F.A. Schraub, P.W. Runstadler, The structure of turbulent boundary layers. J. Fluid Mech. 30, 741–773 (1967).CrossRefGoogle Scholar
  8. 8.
    P.-Å Krogstad, R.A. Antonia, Structure of turbulent boundary layers on smooth and rough walls. J. Fluid Mech. 277, 1–21 (1994).CrossRefGoogle Scholar
  9. 9.
    S. Leonardi, P. Orlandi, L. Djenidi, R.A. Antonia, Structure of turbulent channel flow with square bars on one wall. Int. J. Heat Fluid Flow 25, 384–392 (2004).CrossRefGoogle Scholar
  10. 10.
    S. Leonardi, I. Castro, Turbulent flow over urban canopies Proceedings of AIAA Conference, Seattle, July 2008.Google Scholar
  11. 11.
    S. Leonardi, I. Castro, Channel flow over large cube roughness: a DNS study J. Fluid Mech., in press.Google Scholar
  12. 12.
    J.L. Lumley, Computational modeling of turbulent flows. Adv. Appl. Mech. 18 123–176 (1978).MathSciNetzbMATHCrossRefGoogle Scholar
  13. 13.
    N.N. Mansour, J. Kim, P. Moin, Reynolds-stress and dissipation-rate budgets in a turbulent channel flow. J. Fluid Mech. 194, 15–44 (1988).CrossRefGoogle Scholar
  14. 14.
    P. Orlandi, Fluid Flow Phenomena : A Numerical Toolkit Kluwer Dordrecht, (2000).Google Scholar
  15. 15.
    P. Orlandi, S. Leonardi, DNS of turbulent channel flows with two- and three-dimensional roughness. J. Turbulence 7, 1–22 (2006).CrossRefGoogle Scholar
  16. 16.
    J. Pullen, J.P. Boris, T. Young, G. Patnaik, J. Iselin, A comparison of contaminant plume statistics from a Gaussian puff and urban CFD model for two large cities. Atmos. Environ. 39, 1049–1068, (2005).CrossRefGoogle Scholar
  17. 17.
    R. Reynolds, P. Hayden, I.P. Castro, A.G. Robins, Spanwise variations in nominally two-dimensional rough-wall boundary layers. Exp. Fluids 42, 311–320 (2007).CrossRefGoogle Scholar
  18. 18.
    Y.H. Tseng, C. Meneveau, M. Parlange, Modeling flow around bluff bodies and predicting urban dispersion using large eddy simulation Environ. Sci. Technol. 40, 2653–2662 (2006).CrossRefGoogle Scholar
  19. 19.
    Z-T. Xie, I.P. Castro, LES and RANS for turbulent flow over arrays of wall-mounted obstacles, Flow Tub. Comb. 76, 291–312 (2006).zbMATHCrossRefGoogle Scholar
  20. 20.
    Z-T. Xie, I.P. Castro, Large-eddy simulation for flow and dispersion in urban streets Atmos. Environ. 43, 2174–2185 (2009).Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringUniversity of Puerto Rico at MayaguezMayagüezUSA
  2. 2.School of Engineering SciencesUniversity of SouthamptonSouthamptonUK

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