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| A Numberical Simulation of Effect of Windflow and Gravels’ Geometric Parameters on Aerodynamic Roughness Length |
| Wang Xiao, Zhang Weimin |
| Dunhuang Gobi Desert Ecology and Environment Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China |
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Abstract In this paper, using FLUENT6.3 we simulate effect of wind flow and gravels' geometric parameters on aerodynamic roughness length. The results indicate that aerodynamic roughness is a function of wind flow, and the variation of aerodynamic roughness (z0) with wind speed (u), friction velocity (u*) can be expressed by an exponential fuction: z0=aexp(bu/u*). Gravel height has more significant influence on aerodynamic roughness length than gravel sizes; the aerodynamic roughness increases firstly with gravel density, then decreases. The successful application of FLUENT6.3 in simulation of aerodynamic process of gravel beds is a beneficial attempt.
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Received: 14 August 2013
Published: 20 July 2014
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2014, Vol. 34 
