Papers

2004

LARGE EDDY SIMULATION OF TURBURENT ORGANIZED STRUCTURES WITHIN AND ABOVE URBAN OBSTACLES

Doboku Gakkai Ronbunshuu B
  • KASAMATSU Fumi
  • ,
  • KANDA Manabu
  • ,
  • MORIWAKI Ryo

Volume
48
Number
First page
607
Last page
612
DOI
10.2208/prohe.48.607
Publisher
Japan Society of Civil Engineers

Large Eddy Simulations have been performed for fully developed turbulent flow within and above explicitly resolved simple cube arrays. The model (LES-CITY) was validated in comparison with laboratory experiments. The systematic influence of cubic density on turbulent flow characteristics was investigated through numerical experiments in a wide range of cubic area density (0 to 0.44).<BR>The following results were obtained. 1) The intermittency of flow: the temporally and spatially averaged flow structure confirms the existence of conventionally described canyon flow regime. However, the intermittency of the canyon flow for any cubic densities is large and the stream patterns are never persistent. 2) Turbulent Organized Structures (TOS): TOS are characterized by longitudinally elongated low speed streaks and corresponding streamwise vortices. The streaks in sparse and dense canopy flows are likely to be aligned to the street-line and to the roof-line, respectively.

Link information
DOI
https://doi.org/10.2208/prohe.48.607
CiNii Articles
http://ci.nii.ac.jp/naid/130004043467
ID information
  • DOI : 10.2208/prohe.48.607
  • ISSN : 0916-7374
  • CiNii Articles ID : 130004043467
  • identifiers.cinii_nr_id : 9000254958765

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