This work reports the drag coefficients (C d) for three wind directions measured in low turbulence flow and in turbulent flow with characteristics of the atmospheric boundary layer wind, and the Strouhal numbers (St) of an approximately trapezoidal flanged section, used in the boom girder of a 100 m high port crane. These experimental results were obtained at the Boundary Layer Wind Tunnel of the Dept. Aeronautica at the Universidad Nacional de La Plata, in the range of Reynolds numbers between 30,000 and 180,000. The drag coefficients in the three studied directions showed a reduction for turbulent flow. Further measurements were carried out for the model with an inclination of 801 relative to the flow direction, the position of the crane boom when out of service, giving practically the same drag coefficients.

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Field experiments have been conducted in the semiarid southwest region of La Pampa, Argentina, in order to investigate the effect of different types of windbreak on wind characteristics and growth parameters of wheat (Triticum aestivum, Buck Charrua variety) within the sheltered region. Windbreaks decrease wind speed, reducing damage to the crop and improving yield and quality. Sheltering may improve microclimate conditions for plant growth and protects the soil from wind erosion. Aspects of the sheltering ability of four different windbreaks have been tested: single and double row herbaceous (Tritio secale) shelterbelts, and two different artificial wooden fences, with the same overall average porosity, but with different porosity distributions. Mean velocity, turbulence intensity, skewness distributions and spectral and wavelet analysis have been performed in order to characterise the turbulent flow downstream of the different windbreaks. Wheat grain yield and harvest index were compared with adjacent unsheltered plantations. The single and double row shelterbelts enhanced the grain yield and the harvest index of the protected plants. An influence of the turbulent structure on plant growth is suggested by the different response of plants sheltered by the two types of artificial fences.

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-The objective of this work is the study of the effect of different configurations of turbulators as flow control devices, when an airfoil is immersed in a flow that reproduces the natural turbulent characteristics of the low atmospheric boundary layer. The efficiency of an Eppler 387 airfoil modified with several configurations of turbulators is studied. The tests were performed in a boundary layer wind tunnel using an aerodynamic balance and smoke for flow visualizations.