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

• Autorzy: Coceal O. , Thomas T. G. , Belcher S.
• Języki publikacji: EN

Abstrakty

EN

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.

Słowa kluczowe

EN

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

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2008
• Tom: Vol. 56, no. 3
• Strony: 862--875
• Opis fizyczny: bibliogr. 24 poz.

Twórcy

autor

Coceal O.

autor

Thomas T. G.

autor

Belcher S.

• Department of Meteorology, University of Reading, Reading, UK,

Bibliografia

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