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Acta Geophysica

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Volume 56, Issue 3 (Sep 2008)


Spatially-averaged flow statistics within a canopy of large bluff bodies: Results from direct numerical simulations

Omduth Coceal
  • Department of Meteorology, University of Reading, Reading, UK
  • Email:
/ T. Thomas
  • School of Engineering Sciences, University of Southampton, Highfield, Southampton, UK
  • Email:
/ Stephen Belcher
  • Department of Meteorology, University of Reading, Reading, UK
  • Email:
Published Online: 2008-07-01 | DOI: https://doi.org/10.2478/s11600-008-0025-y


The flow within a canopy of large bluff bodies is highly turbulent and spatially heterogeneous. Results from direct numerical simulations over groups of cubical obstacles are analysed using the double-averaging methodology. The obstacles occupy a significant fraction of the canopy space; this gives rise to substantial dispersive stresses within the canopy. The underlying bluff-body turbulent dynamics is different from typical canopy turbulence, and this is reflected in the double-averaged statistics. The spatially-averaged velocities, stresses and drag force depend significantly upon the layout of the obstacles. An ongoing challenge is to parameterise these spatially-averaged quantities in terms of the obstacle geometry and layout.

Keywords: bluff bodies; direct numerical simulations; double-averaging methodology; rough-wall channel flow; turbulent channel flow

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About the article

Published Online: 2008-07-01

Published in Print: 2008-09-01

Citation Information: Acta Geophysica, ISSN (Online) 1895-7455, ISSN (Print) 1895-6572, DOI: https://doi.org/10.2478/s11600-008-0025-y. Export Citation

© 2008 Institute of Geophysics, Polish Academy of Sciences. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. (CC BY-NC-ND 3.0)

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