Wind tunnel observations about the shelter effect of porous fences on the sand particle movements

摘要

The effect of porous wind fences on the wind erosion of small sand particles from a two-dimensional triangular prism pile of sand was investigated experimentally. The mean velocity and turbulence intensity profiles measured at the sand pile location were simulated to fit to the atmospheric boundary layer over open terrain. Flow visualization was carried out to qualitatively determine the movement of the wind-blown sand particles. In addition, the threshold velocity was measured using a digital image processing system at a range of values of the fence porosity ε, particle size D_p and sand pile height h.