固沙剂沙障防风固沙效益的风洞模拟OA

[Objective]This study aims to clarify the effects of sand-fixing agent sand barriers on the airflow field,surface erosion-deposition variations,and sand particle transport,thereby providing a basis for the deployment of such barriers to control shifting sand.[Methods]In a wind tunnel,grid sand barriers sprayed with sand-fixing agent with a scale ratio of 1∶1 were set up on slope gradients of 0°(flat sand surface),15°,and 30°.The effects of the barriers on the airflow field,sand transport amount,and erosion-deposition conditions within the grid sand barriers were simulated and measured at five wind speeds.[Results]1)The airflow field comprised three zones:a wind deceleration zone in front of the barrier,a wind acceleration zone above the barrier,and a wind deceleration zone behind the barrier.The area from-10H to-1H in front of the first sand barrier was the wind speed reduction zone,the area from-1H to 0H above the barrier was the wind speed increase zone,and the area from 0H to 5H behind the barrier was the wind speed reduction zone.The area from 5H to 8H was the wind speed recovery zone.Similar patterns were observed for the second and third sand barriers.Within the grids formed by three consecutive barriers,the wind speed showed a variation trend of decreasing,increasing,and decreasing.The wind speed reduction percentages were 51.97％-59.05％,28.14％-32.25％,and 47.15％-53.97％,respectively.2)At different slope gradients and wind speeds,the relationship between sand transport amount and height followed an exponential function.On the flat sand surface,the sand transport amount decreased with height,while at 15° and 30° slope gradients,it increased with height.The sand transport amount at each height and total sand transport amount decreased with increasing slope but increased with increasing wind speed.Additionally,the height at which the sand transport amount was concentrated showed an upward trend.3)On the flat sand surface,both the depth and area of wind erosion within the barriers increased with increasing wind speed.Slope had a significant impact on wind erosion.With increasing slope gradient,erosion in front of the windward barrier weakened,erosion on the windward barrier intensified,sand deposition on the leeward barrier became pronounced,and erosion behind the leeward barrier occurred only at high wind speeds(＞18 m/s).The barrier ridges remained completely intact at all tested wind speeds and slope gradients.[Conclusion]Sand-fixing agent sand barriers demonstrate good windbreak and sand-fixation benefits.Moreover,sand sprayed with the sand-fixing agent can avoid wind erosion.These findings provide theoretical support for sand barrier configuration and offer a new material and approach for desertification control.