新疆S214省道高立式芦苇沙障合理间距分析

以新疆S214省道沙害防治区段为背景,应用CFD(computational fluid dynamics)数值模拟方法分析了高立式芦苇沙障周围的风沙流场,结果表明:高立式芦苇沙障周围流场可分为迎风侧减速区,上方加速区和背风侧恢复区,背风侧无明显涡流区生成,沙障间的合理间距与风速呈负相关。现场布置模式对20 m·s^-1的风沙流有较好防护效果,低于此风速时,第二道沙障背风侧基本无恢复区生成,后两道沙障迎风侧积沙较多且紧贴沙障分布,压埋沙障速度较快。通过相贴原理优化沙障间距,可以充分发挥各道沙障的防护作用,有效抵御风沙流侵袭,适当延长沙障使用年限。根据前人观测数据、现场调查和数值模拟结果,建议研究区内高立式芦苇沙障间距宜为20~25 m。该研究结果可为研究区内高立式芦苇沙障的合理布置提供理论依据,也可为其他风沙防护工程的建设提供参考。

Reasonable spacing of high-parallel reed sand barriers along the Xinjiang S214 provincial highway

The CFD (computational fluid dynamics) numerical simulation method was used to study the windsand flow fields around the high-parallel reed sand barrier of the Xinjiang S214 provincial highway sand control section. The results showed that the flow field division around the high-parallel reed sand barrier can be divided into the windward side deceleration zone,the upper acceleration zone,and the leeward side recovery zone;no obvious vortex zone formation was observed on the leeward side. Reasonable spacing between sand barriers was found to be negatively correlated with wind speed. The field layout mode has a better protective effect on wind-sand flows of 20 m·s^-1;when the wind velocity is lower,minimal eddy currents developed on the leeward side of the second sand barrier. More sand accumulated on the windward side of the latter two sand barriers and they are close to the distribution of sand barriers. The burial speed of sand barriers is also faster. Through optimizing the distance between sand barriers based on matching principles,the protection of each sand barrier can be maintained,effectively resisting the invasion of sand and prolonging the service life of the barriers. According to previous observational data,field investigation,and numerical simulation results,it is suggested that high-parallel reed sand barriers in the study area should be spaced by 20-25 m. The results of this research provide a theoretical basis for the reasonable spacing of high-parallel reed sand barriers along the Xinjiang S214 provincial highway,and also provide a reference for the construction of other wind-sand protection projects.