Effects of sand sedimentation and wind erosion around sand barrier: Numerical simulation and wind tunnel test studies

Based on numerical simulations, this study highlights the sedimentation and erosion problems around a sand barrier through the relationship between the shear stress of the surface around the sand barrier and the critical shear stress of sand grains. The numerical simulation results were verified using data measured by the wind tunnel test. The results showed that when the porosity was the same, the size and position of the vortex on the leeward side of the sand barrier were related to the inlet wind speed. As the wind speed increased, the vortex volume increased and the positions of the separation and reattachment points moved toward the leeward side. When the porosity of the sand barrier was 30%, the strength of the acceleration zone above the sand barrier was the highest, and the strength of the acceleration zone was negatively correlated with the porosity. Sand erosion and sedimentation distance were related to wind speed. With an increase in wind speed, the sand grain forward erosion or reverse erosion areas on the leeward side of the sand barrier gradually replaced the sedimentation area. With an increase in porosity, the sand sedimentation distance on the leeward side of the sand barrier gradually shortened, and the sand erosion area gradually disappeared. The sand sedimentation distance on the leeward side of the sand barrier with 30% porosity was the longest. The numerical simulation results were in good agreement with the wind tunnel test results. Based on the sand erosion and sedimentation results of the numerical simulation and wind tunnel test, when the porosity was 30%, the protection effect of the High Density Polyethylene (HDPE) board sand barrier was best.