新疆和田河流域灌丛沙堆风洞流场的实验研究（Ⅰ）

摘要/Abstract

摘要： 灌丛沙堆是一种重要的风积地貌类型,风力、沙源、植物是影响灌丛沙堆发育的主要因素。依据风沙运动实验相似理论,以新疆和田河流域实测的灌丛沙堆数据为基础,按40∶1的比例缩小制作成无植被“灌丛沙堆”模型,在风洞中选用区间在6~14 m\5s-1的5组不同风速分别对沙堆模型作纯气流模拟实验流场观测,探讨在不同风力作用下灌丛沙堆表面的流场结构变化特征。模拟实验表明,气流在半球形沙堆迎风坡下部受到正面风压影响有较明显反射涡流,丘顶具有高速气流风蚀区域,而圆锥形沙堆迎风坡气流均匀爬坡加速,背风坡涡流强盛,因此两者在无沙情况下的纯气流流场结构特征、沙堆形态动力平衡特点有较明显差异。

关键词: 无植被沙堆, 风洞实验, 模拟流场

Abstract: Nabkha dune is a kind of typical aeolian landform. The wind power, sand source and plant are the mainly influencing factors of the development of nabkha. In this paper, two models of sand mounds without vegetation were made in 40∶1 proportion in wind tunnel, according to similarity theory in wind-sand movement experiments, and on the base of Nabkha data surveyed in the Hetian river basin in Xinjiang. The experimental wind speed are separately 6, 8, 10, 12, 14 m\5s-1. The flow pattern over semispherical sand mound model showed that obvious reflected vortex appeared at the upwind bottom influenced by facade wind pressure, and there was eroded region by strong wind at the top of sand mound. In contrast, the airflow increased equably along the upwind slope of conical sand mound, and vortex at leeward side was very strong. The structure of pure airflow pattern and the dynamic equilibrium point of dune shape are different between semispherical and conical of sand mound.

Key words: sand mound without vegetation, wind-tunnel experiment, simulated flow pattern

中图分类号:

P931.3+X169

李志忠;武胜利;*;肖晨曦;孙秋梅;刘丽梅;张中华. 新疆和田河流域灌丛沙堆风洞流场的实验研究（Ⅰ）[J]. 中国沙漠, 2007, 27(1): 9-14.

LI Zhi-zhong;WU Sheng-li;XIAO Chen-xi;SUN Qiu-mei;LIU Li-mei;ZHANG Zhong-hua. Study on Wind-tunnel Simulated Flow Pattern over Nabkha in Hetian River Basin,Xinjiang (Ⅰ)[J]. JOURNAL OF DESERT RESEARCH, 2007, 27(1): 9-14.

参考文献

[1]朱震达,陈治平,吴正,等.塔克拉玛干沙漠风沙地貌研究[M].北京:科学出版社,1981.
[2]Cook R C,Warren A,Goudie A S.Desert Geomorphology[M].Gower Street,London WC1E 6BT:UCL Press Limited,University College London,1993.
[3]Pye K,Tsoar H.Aeolian Sand and Dunes[M].15/17 Broadwick Street,London W1V 1FP,UK:Unwin Hyman Ltd,1990.
[4]吴正,等.风沙地貌与治沙工程学[M].北京:科学出版社,2003.
[5]Hesp P A.The formation of shadow dunes[J].Journal of Sedimentary Petrology,1981,51:101-112.
[6]McKenna N C,Lancaster N,Nickling W G.The effect of unsteady winds on sediment transport on the stoss slope of a transverse dune,Silver Peak,NV,USA [J].Sedimentology,2000,47:211-226.
[7]Tseo G.Two types of longitudinal dunefields and possible mechanisms for their development[J].Earth Surface Processes and Landforms,1993,18:627-643.
[8]Walker I J.Secondary air flow and sediment transport in the lee of a reversing dune[J].Earth Surface Processes and Landforms,1999,24:437-448.
[9]Stam J M T.On the modeling of two-dimensional Aeolian dunes[J].Sedimentology,1997,44:127-141.
[10]张家武,陈广庭.塔克拉玛干沙漠中部地区线形沙丘表面动力学过程[J].中国沙漠,1999,19(2):128-134.
[11]王训明,董治宝,赵爱国.简单横向沙丘表面物质组成、气流分布及其在动力学过程中的意义[J].干旱区资源与环境,2004,18(4):29-34.
[12]朱震达,陈广庭,等.中国土地沙质荒漠化[M].北京:科学出版社,1994.
[13]凌裕泉,吴正,刘绍中,等.新月形沙丘形态的模拟实验研究[J].地理科学,1998,18（1）:88-93.
[14]刘小平,董治宝.砾石床面的空气动力学粗糙度[J].中国沙漠,2003,23(1):38-46.
[15]胡孟春,赵爱国,李农.沙坡头铁路防护体系阻沙效益风洞实验研究[J].中国沙漠,2002,22(6):598-602.
[16]凌裕泉,屈建军.稀疏天然植被对输沙量的影响[J].中国沙漠,2003,23（1）:12-18.
[17]刘小平,董治宝.直立植被粗糙度和阻力分解的风洞实验研究[J].中国沙漠,2002,22（1）:82-88.
[18]李志忠,关有志.纵向沙丘和横向沙丘模拟流场的实验研究[J].中国沙漠,1996,16（4）:360-363.
[19]李志忠,陈广庭.金字塔沙丘风洞流场结构的实验研究——兼论金字塔沙丘的发育模式[J].中国沙漠,1995,15（3）:227-233.
[20]屈建军,凌裕泉.金字塔沙丘形成机制的初步观测与研究[J].中国沙漠,1992,12（4）:19-27.
[21]张伟民,李孝泽,屈建军,等.金字塔沙丘地表气流场及其动力学过程研究[J].中国沙漠,1998,18（3）:215-220.
[22]凌裕泉,吴绍中,吴正,等.金字塔沙丘形成的动力条件分析[J].中国沙漠,1997,17（2）:112-118.
[23]哈斯,王贵勇,董光荣.腾格里沙漠东南缘格状沙丘表面气流及其地貌学意义[J].中国沙漠,2000,20（1）:30-34.
[24]哈斯,董光荣,王贵勇.腾格里沙漠东南缘格状沙丘的形态动力学研究[J].中国科学（D辑）,1999,29（5）:466-471.
[25]Wiggs G F S,Livingstone I,Warren A.The role of streamline curvature in sand dune dynamics:evidence form field and wind tunnel measurements[J].Geomorphology,1996,17:29-46.