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DOI	10.1016/j.geomorph.2021.107699
	Field measurements of crestal flow direction and turbulent flow over two transverse dune ridges
	Zhang, Zhengcai; Dong, Zhibao
通讯作者	Zhang, ZC (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, 260 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China.
发表日期	2021
ISSN	0169-555X
EISSN	1872-695X
卷号	383
英文摘要	Turbulent airflow is a fundamental factor that controls the geomorphology of sand dune systems, especially dune expansion and sandy desertification. However, little is known about turbulent air flow in dune systems, and this limits efforts to control dune expansion and sandy desertification. To obtain some of the missing information, we calculated the turbulent airflow characteristics over a transverse dune in the Tengger Desert in southeastern China. We found that the angle of airflow at the dune crest controls flow angles at middle of the dune's stoss slope and at the toe of the leeward slope, and also controls the turbulent flow characteristics over the dune surface. The critical wind direction was from the NW (wind directions ranged from 355 degrees to 45 degrees to the crest perpendicular line [CPL]) and SE (wind directions ranged from 65 degrees to 165 degrees with respect to the CPL), and about 20 degrees and 25 degrees with respect to the CPL for northwesterly winds and southeasterly winds, respectively. The kinematic Reynolds' stress (RSk), streamwise turbulence intensity (CVu), and total kinetic energy (TKE) were largest close to the critical wind direction for winds from the NW, indicating that dune movement was mainly controlled by the critical wind direction. However, TKE, RSk, and CVu differed between southeast and northwest winds; for southeasterly winds, they were largest for wind directions from 65 degrees to 115 degrees with respect to the CPL and similar to the values for wind directions from 115 degrees to 165 degrees with respect to the CPL, indicating asymmetrical sand movement. We conclude that, for closely spaced transverse dunes, sand transport is controlled by the critical wind directions; this indicates that efficient control of sand movement and sandy desertification will benefit from sand-control structures that block airflow from the critical wind directions. (C) 2021 Elsevier B.V. All rights reserved.
关键词	SECONDARY AIR-FLOW PRINCE-EDWARD-ISLAND SEDIMENT TRANSPORT GREENWICH DUNES FOREDUNE WIND DYNAMICS LEE MODEL GEOMORPHOLOGY
英文关键词	Turbulence; Critical wind direction; Inter-dune area; Transverse dune
语种	英语
WOS研究方向	Physical Geography ; Geology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS记录号	WOS:000640909900005
来源期刊	GEOMORPHOLOGY
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/253646
作者单位	[Zhang, Zhengcai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Gansu, Peoples R China; [Dong, Zhibao] Shaanxi Normal Univ, Sch Geog & Tourism, Xian, Shanxi, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Zhengcai,Dong, Zhibao. Field measurements of crestal flow direction and turbulent flow over two transverse dune ridges[J]. 中国科学院西北生态环境资源研究院,2021,383.
APA	Zhang, Zhengcai,&Dong, Zhibao.(2021).Field measurements of crestal flow direction and turbulent flow over two transverse dune ridges.GEOMORPHOLOGY,383.
MLA	Zhang, Zhengcai,et al."Field measurements of crestal flow direction and turbulent flow over two transverse dune ridges".GEOMORPHOLOGY 383(2021).