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Large Eddy Simulation of Coherent Structures over Forest Canopy

  • K. Gavrilov
  • G. Accary
  • D. Morvan
  • D. Lyubimov
  • O. Bessonov
  • S. Méradji
Part of the Notes on Numerical Fluid Mechanics and Multidisciplinary Design book series (NNFM, volume 110)

Abstract

This paper deals with the numerical simulation (using a LES approach) of the interaction between an atmospheric boundary layer (ABL) and a canopy, representing a forest cover. This problem was studied for a homogeneous configuration representing the situation encountered above a continuous forest cover, and a heterogeneous configuration representing the situation similar to an edge or a clearing in a forest. The numerical results, reproduced correctly all the main characteristics of this flow, as reported in the literature: the formation of a first generation of coherent structures aligned transversally from the wind flow direction, the reorganisation and the deformation of these vortex tubes to horse shoe structures. The results obtained, introducing a discontinuity in the canopy (reproducing a clearing or a fuel break in a forest), were compared with experimental data collected in a wind tunnel. The results confirmed the existence of a strong turbulence activity inside the canopy at a distance equal to 8 times the height of the canopy, referenced in the literature as an Enhance Gust Zone (EGZ) characterized by a local peak of the skewness factor.

Keywords

Large Eddy Simulation Coherent Structure Atmospheric Boundary Layer Forest Canopy Vortex Tube 
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.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • K. Gavrilov
    • 1
  • G. Accary
    • 2
  • D. Morvan
    • 3
  • D. Lyubimov
    • 1
  • O. Bessonov
    • 4
  • S. Méradji
    • 5
  1. 1.Department of Theoretical PhysicsPerm State UniversityPermRussia
  2. 2.Université Saint Esprit de KaslikJounieh Lebano
  3. 3.Technopôle de Château GombertUNIMECAMarseille cedex 13France
  4. 4.Institute for Problem in Mechanics RASMoscowRussia
  5. 5.M2P2 CNRS-Université d’Aix-MarseilleMarseilleFrance

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