Turbulence burst over four micro-topographies in the wind tunnel

doi:10.1016/j.catena.2016.04.017

	Turbulence burst over four micro-topographies in the wind tunnel
	Sun, WH; Huang, N; He, W; Huang, N (reprint author), Lanzhou Univ, Key Lab Mech Disaster & Environm Western China, Minist Educ China, Lanzhou 730000, Peoples R China.
	2017-01
会议日期	MAY 31-JUN 05, 2015
会议地点	El Paso, TX
关键词	Wind-blown sand movement Wind tunnel experiment Different roughness Turbulence burst
卷号	148
DOI	10.1016/j.catena.2016.04.017
页码	138-144
英文摘要	Investigating the mechanisms of wind-sand movement is essential to deeply understand sand storm and desertification process, and further to control the wind-sand hazards. It is considered that turbulence burst may have great influence on the motion of sand particles. But current theoretical and experimental studies mostly concentrate on the turbulence burst over flat surface or in the water. Sand dunes and sand ripples are basic forms of desert landscape, and the slope gradient will inevitably affect the frequency of turbulence burst.in this paper, instantaneous velocities over 4 different sand surfaces, including smooth flat bed, flat sand bed, sand bed with ripples and slope bed, are measured using one-dimensional hot wire detector. The results show that for the slope sand surface, wind field in leeward slope region is a buffering zone, which doesn't obey logarithmic function. On the flat sand surface, the distribution of turbulence intensity and Reynolds normal stress are gradually decreasing along the height of boundary layer: On the slope sand surface, the stronger turbulence behavior happens near the top of slope. Based on Mu-level method analysis, it is found that the turbulence bursts on both flat sand surface and sand ripples mainly occur near the surface, and gradually decrease with the height. Compared to flat sand surface, the burst frequency is 30%- 50% higher on the sand ripples surface, which indicates that micro topography have an influence on the turbulence burst. This work may be helpful in understanding the initiation and transportation of sand storm, as well as the desertification process. (C) 2016 Elsevier B.V. All rights reserved.
会议录	CATENA
会议录出版地	AMSTERDAM
学科主题	Geology ; Agriculture ; Water Resources
语种	英语
ISSN号	0341-8162
WOS记录号	WOS:000389166800005
内容类型	会议论文
源URL	[http://ir.lzu.edu.cn/handle/262010/189630]
专题	土木工程与力学学院_会议论文
通讯作者	Huang, N (reprint author), Lanzhou Univ, Key Lab Mech Disaster & Environm Western China, Minist Educ China, Lanzhou 730000, Peoples R China.
推荐引用方式 GB/T 7714	Sun, WH,Huang, N,He, W,et al. Turbulence burst over four micro-topographies in the wind tunnel[C]. 见:. El Paso, TX. MAY 31-JUN 05, 2015.