干旱区生态环境知识资源中心(Arid): 柽柳灌丛沙堆三维流场随背景植被变化的风洞实验

Arid

	柽柳灌丛沙堆三维流场随背景植被变化的风洞实验
其他题名	Wind Tunnel Simulation of the Three-Dimensional Airflow Patterns around Tamarix ramosissima Nebkhas under the Change of Background Vegetation Coverage
	谭凤翥 1; 王雪芹 2; 王海峰 2; 徐俊荣 2; 袁鑫鑫 1
来源期刊	中国沙漠
ISSN	1000-694X
出版年	2018
卷号	38 期号:1 页码:48-57
中文摘要	以塔克拉玛干沙漠南缘沙漠-绿洲过渡带广泛分布的柽柳灌丛沙堆及丘间地植物为原型,依据风沙运动相似理论,制作5组背景植被盖度灌丛沙堆模型,在风洞中进行风流场变化规律模拟实验。结果表明:柽柳沙堆三维流场结构可划分为6个区域,即沙堆前减速区、沙堆迎风坡加速区、沙堆两侧急流区、沙堆背风侧强涡流区、沙堆后尾流恢复区和沙堆上空混合加速区。灌丛沙堆对流场结构影响范围为沙堆前10H到沙堆后14H区段,旁侧影响宽度不超过沙堆宽度的3/4,垂直方向上主要影响灌丛沙堆总高度相对应的下方区域,最大不超过灌丛沙堆总高度的2倍。风速变化不构成对流场结构的影响,但背景植被变化对流场结构影响明显。随着植被盖度增大,沙堆前减速区和沙堆后尾流恢复区范围扩大,两侧急流区和背风侧涡流区范围缩小。背景植被的出现明显降低了其所在高度层的风速,柽柳沙堆各分区地表加速率均随背景植被盖度呈指数规律下降,当植被盖度在16%时加速率变化趋于平缓。从维护绿洲安全的角度出发,根据风沙动力学原理可将16%视为灌丛沙堆科学保育中可能的临界背景植被覆盖值。
英文摘要	This paper aimed to find out the law of three-dimensional airflow patterns around Tamarix ramosissima nebkhas under different background vegetation coverages.In order to reveal erosion and deposition process mechanism and provide a theoretical basis for scientific conservation of nebkhas,the Tamarix ramosissima nebkhas and sparsifolia at southern edge of the Taklimakan Desert-oasis ecotone were chosen as experimental model and wind velocity was investigated through wind tunnel simulation.Results showed that the three-dimensional airflow structure of Tamarix ramosissima nebkhas can be divided into six regions:the deceleration zone before nebkhas,the acceleration region of nebkhas windward,the high speed zone on both sides of nebkhas,the strong vortex area on leeward side of nebkhas,the recovery zone after nebkhas and the mixed acceleration zone above nebkhas.The influence region of nebkhas on airflow patterns was from -10H to 14H in horizontal direction and the width of side influence zone was less than 3/4 of nebkhas width.While in vertical direction,the airflow patterns were significantly affected by the area below the overall height of nebkhas and the maximum influence height was less than 2H.The background vegetation coverage played an important role in affecting the airflow patterns instead of wind velocity.With the increase of background vegetation coverage,the deceleration zone and recovery zone were expanded at front of nebkhas and behind nebkhas,respectively.Meanwhile,the strong vortex zone and high speed zone became shrinked on lee side and both sides of nebkhas.The wind velocity was significantly reduced at the height where the background vegetation existed.The airflow acceleration rates at each region of nebkhas showed a nearly exponential decay with background vegetation coverage.When the coverage was more than 16% ,the acceleration rate tended to be steady.From the perspective of maintaining oasis security and according to the principle of wind-blown sand dynamics,background vegetation coverage should be maintained at least at 16% in desert-oasis ecotones so as to maintaining security and stability of oases.
中文关键词	柽柳灌丛沙堆 ; 三维流场 ; 背景植被盖度 ; 风洞实验
英文关键词	Tamarix ramosissima nebkhas three-dimensional airflow patterns background vegetation coverage wind tunnel test
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOSCIENCES MULTIDISCIPLINARY
WOS研究方向	Geology
CSCD记录号	CSCD:6160254
来源机构	中国科学院新疆生态与地理研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/238741
作者单位	1.中国科学院新疆生态与地理研究所莫索湾沙漠研究站;;中国科学院大学, ;;, 乌鲁木齐;;, 新疆;;北京 830011;;100049, 中国; 2.中国科学院新疆生态与地理研究所莫索湾沙漠研究站, 乌鲁木齐, 新疆 830011, 中国
推荐引用方式 GB/T 7714	谭凤翥,王雪芹,王海峰,等. 柽柳灌丛沙堆三维流场随背景植被变化的风洞实验[J]. 中国科学院新疆生态与地理研究所,2018,38(1):48-57.
APA	谭凤翥,王雪芹,王海峰,徐俊荣,&袁鑫鑫.(2018).柽柳灌丛沙堆三维流场随背景植被变化的风洞实验.中国沙漠,38(1),48-57.
MLA	谭凤翥,et al."柽柳灌丛沙堆三维流场随背景植被变化的风洞实验".中国沙漠 38.1(2018):48-57.