Authors

Abstract

Strong wind and sand activities will seriously damage the ecological restoration and agricultural safety production on the edge of desert areas, resulting in irreversible economic losses. In order to prevent and protect the agro-ecological environment in the wind-blown sand area, this paper constructs a combination of double-row vertical nylon net sand barrier and grass grid sand barrier. Through numerical simulation and wind tunnel experiment, the protection benefits of double-row vertical nylon net sand barrier and grass grid under different spacing conditions are analyzed, and the layout conditions with optimal spacing are obtained. The results show that when the spacing between double-row vertical sand barrier and grass grid is 5H-10H, the airflow velocity behind the double-row vertical sand barrier cannot be fully developed, the increase of airflow velocity is small, and the average wind prevention efficiency is above 85%. The effective protection distance com-pletely covers the entire combined sand barrier area, and a large number of sand particles near the surface are fixed to the grass grid, so the sand resistance rate is over 77%. The combined sand barrier has a good cooperative protection effect and achieves efficient wind prevention and sand fixation. The wind tunnel experiment verifies the reliability of the results. It also realizes efficient wind prevention and sand fixation under extreme wind and sand weather, and avoids sand burial on farmland and ecological restoration areas caused by extreme wind and sand weather.

Abstract in Chinese

强烈的风沙活动会对沙漠地区边缘地带的生态恢复建设和农业安全生产形成严重破坏，造成不可逆转的经济损失。为预防保护风沙地区的农业生态环境，本文构建了双排高立式尼龙网沙障＋草方格联合沙障，通过数值模拟和风洞实验，分析双排高立式尼龙网沙障与草方格不同间距条件下的防护效益，得到了最优间距的布设工况。结果表明，当双排高立式沙障与草方格间距为5H-10H时，双排高立式沙障后气流速度无法充分发育，气流速度增大幅度较小，平均防风效率达到85％以上，有效防护距离完全覆盖整个联合沙障区域，近地表沙粒大量被固定至草方格内，阻沙率达到77％以上，联合沙障协同防护作用较好，实现高效的防风固沙。经风洞实验测试，验证了结果的可靠性。实现了在极端风沙天气下高效的防风固沙，避免极端风沙天气对农田和生态修复区造成沙埋。