Abstract
An experimental study of the modification of the neutral wind profile as air flows to a rougher surface is presented. The analysis is based on wind profiles measured at four locations extending about 100 m downwind from the leading edge of a mature wheat crop. The form of the modified wind profile, and the rate of internal boundary-layer growth are analyzed in terms of a non-dimensional wind velocity. Friction velocities, based on wind-profile computations, are also examined at different points in the flow field. Boundary-layer growth was more rapid than expected, but could be approximated by a 4/5th power of the fetch if a roughness factor is included. It is suggested that simple height:fetch ratios, such as 1:100 be avoided, especially where large roughness-length changes are involved.
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Munro, D.S., Oke, T.R. Aerodynamic boundary-layer adjustment over a crop in neutral stability. Boundary-Layer Meteorol 9, 53–61 (1975). https://doi.org/10.1007/BF00232253
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DOI: https://doi.org/10.1007/BF00232253