img

官方微信

高级检索

中国沙漠 ›› 2020, Vol. 40 ›› Issue (6): 22-32.DOI: 10.7522/j.issn.1000-694X.2020.00064

• • 上一篇    下一篇

青藏铁路错那湖段挡沙墙风沙两相流数值模拟

周琪智1(), 赵洋1,2, 高广磊1,2(), 丁国栋1,2, 张英1   

  1. 1.北京林业大学,水土保持学院/水土保持国家林业和草原局重点实验室,北京 100083
    2.北京林业大学,宁夏盐池毛乌素沙地生态系统国家定位观测研究站,北京 100083
  • 收稿日期:2020-03-13 修回日期:2020-06-07 出版日期:2020-12-09 发布日期:2020-12-09
  • 通讯作者: 高广磊
  • 作者简介:高广磊(E-mail: gaoguanglei@bjfu.edu.cn
    周琪智(1999—),男,四川西昌人,本科生,研究方向为荒漠化防治。E-mail: zhouqizhi@bjfu.edu.cn
  • 基金资助:
    国家公益性行业(林业)科研专项(201504401);北京林业大学“国家级大学生创新创业训练计划”项目(G201910022017)

Numerical simulation on wind-sand two-phase dynamic characteristic of sand-blocking fences in the Cuona Lake section of the Qinghai-Tibet Railway

Qizhi Zhou1(), Yang Zhao1,2, Guanglei Gao1,2(), Guodong Ding1,2, Ying Zhang1   

  1. 1.School of Soil and Water Conservation Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China
    2.Yanchi Ecology Research Station of the Mu Us Desert,Beijing Forestry University,Beijing 100083,China
  • Received:2020-03-13 Revised:2020-06-07 Online:2020-12-09 Published:2020-12-09
  • Contact: Guanglei Gao

摘要:

青藏铁路错那湖段风沙灾害严重,科学评价和系统优化铁路防护体系对于保障青藏铁路安全运行具有重要意义。基于野外调查和计算流体力学,采用Fluent欧拉双方程模型模拟错那湖段挡沙墙周围风沙两相流运动。结果表明:(1)在无沙物质沉降时,挡沙墙后遮蔽效应区面积可达65.34%;随沙物质不断沉积,起始沉积位置前移,防护效益逐渐减弱。(2)流场可划分为7个功能区,沙物质在耗散减速区、涡旋沉降区发生减速、沉降。(3)挡沙墙周围沙物质受涡旋作用,在1~1.5倍挡沙墙高度范围内开始沉积,第二道挡沙墙后沙物质堆积体积大于第一道。(4)上部倾斜、下部大孔隙的新型挡沙墙,可使起始沉积位置后移1.47倍,提高防护效益1.32倍以上。涡量生成与挡沙墙结构存在密切关系,风沙两相流能量在挡沙墙附近大量损耗,沙物质在旋流中沉降堆积,靠近路基挡沙墙存在被掩埋风险。研究可为沙漠铁路风沙灾害防护体系建设提供理论依据和科学支撑。

关键词: 风沙灾害, 计算流体力学, 防护体系, 涡旋作用

Abstract:

The Cuona Lake section of the Qinghai-Tibet Railway is seriously affected by wind-sand disasters. Therefore, scientific assessment and systematic optimization of the protection system are of important significance to provide a firm basis for the safe operation of the Qinghai-Tibet Railway. Based on the field investigation and computational fluid dynamics, the wind-sand two-phase flow around sand-blocking fences was simulated using the Eulerian Model. The results indicated that: (1) The effective protection area was 65.34% without sediment deposition behind the fences. With the deposition, the protective benefits gradually diminish after the deposit location antedisplacement. (2) The flow field was divided into 7 regions, and the sediments deposited in the dissipation and vortex effect area. (3) The sand particles began to deposit within 1-1.5 times of the fence’s height affecting by vortex effect. Furthermore, the accumulative deposition after the second fence was larger than the first one. (4) A new sand-blocking fence was proposed characterized by the slant upper structure and microporous bottom. This fence moved the deposition location backward for 1.47 times than the original fence and increased 1.32 times for the effective protection distance. The vorticity is closely related to the sand-blocking fence structure. The subgrade is at a high risk of sand burial due to the energy consumption and sediment deposition around the fence. This study provides a theoretical basis and scientific support for the railway protection system against wind-sand disasters.

Key words: wind-sand disaster, computational fluid dynamics, protection system, vortex effect

中图分类号: