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Acta Geophysica

, 56:862 | Cite as

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

  • Omduth Coceal
  • T. Glyn Thomas
  • Stephen E. Belcher
Research Article

Abstract

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.

Key words

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

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Copyright information

© © Versita Warsaw and Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Omduth Coceal
    • 1
  • T. Glyn Thomas
    • 2
  • Stephen E. Belcher
    • 1
  1. 1.Department of MeteorologyUniversity of ReadingReadingUK
  2. 2.School of Engineering SciencesUniversity of SouthamptonHighfield, SouthamptonUK

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