几种典型戈壁床面风沙流特性比较

摘要/Abstract

摘要： 通过不同材料覆盖的戈壁床面风沙流特性风洞模拟实验,发现对于棱角状砾石戈壁床面,地表动力学粗糙度随风速的增加而增加;而卵石床面,地表动力学粗糙度随风速的增加呈减小趋势。戈壁床面风速随高度的分布同样满足对数规律,棱角状砾石床面对风速的减弱程度相对于卵石床面更趋于显著。沙粒与戈壁床面棱角状砾石发生碰撞时其起跳高度增大,引起含沙量随高度分布不再满足流沙地表的指数衰减规律,而呈“象鼻效应”,出现拐点。戈壁地表输沙率与风速服从幂函数关系,但其幂指数远大于流沙地表。输沙率与风速之间幂函数关系中幂指数的取值主要受控于地表粒度组成。

关键词: 动力学粗糙度, 风速廓线, 流场结构, 风洞模拟, 戈壁

Abstract: The goal of this paper is to reveal the characteristics of sand-blown flow over Gobi surfaces based on wind tunnel simulation experiments. Results are shown as follows. Aerodynamic roughness increases with increase of wind speed on simulated gravel Gobi surface, but deceases with increase of wind speed on simulated pebble Gobi surface. Wind speed varies logarithmically with height over simulated Gobi surface. The weaken effect of simulated gravel Gobi surface on wind speed is more obvious than that on simulated pebble Gobi surface. Sand transportation over simulated Gobi surface does not follow the exponential decreasing law with the increase of height as over mobile sand surface because the bounced angle of sand grain will increase when it collides with gravel on Gobi surface, and appears an inflexion and takes on "trunk-shaped". Sand transportation rate presents a power-functioned correlation with wind speed, but its power exponent is far greater than that on mobile sand surface. The value of the power exponent mainly depends on particle size composition of underlying surface.

Key words: aerodynamic roughness, wind speed profile, airflow field, wind tunnel simulation experiment, Gobi

中图分类号:

X169

屈建军, 张克存, 张伟民, 廖空太, 牛清河, 韩庆杰. 几种典型戈壁床面风沙流特性比较[J]. 中国沙漠, 2012, 32(2): 285-290.

QU Jian-jun, ZHANG Ke-cun, ZHANG Wei-min, LIAO Kong-tai, NIU Qing-he, HAN Qing-jie. Characteristics of Sand-blown Flow over Simulated Gobi Surfaces[J]. JOURNAL OF DESERT RESEARCH, 2012, 32(2): 285-290.

参考文献

[1]董治宝,屈建军.《库姆塔格沙漠地貌图》说明书[M].北京:科学出版社,2009:41.

[2]王涛,陈广庭.中国的沙漠、戈壁[M].上海:上海科学技术文献出版社,2008:216-217.

[3]吴正.风沙地貌与治沙工程学[M].北京:科学出版社,2003:61-63.

[4]王自龙,赵明,王立,等.民勤绿洲外围不同下垫面条件下风沙流流量的观测[J].湖北农业科学,2009,48(4):851-856.

[5]杨斌,王元,张洋.风沙流中气固两相速度场的PIV-PLIF测量[J].西安交通大学学报,2009,43(7):101-104.

[6]Chepil W S.Dynamics of wind erosion:Nature of movement of soil by wind[J].Soil Science,1945,60:305-320.

[7]董玉祥,马骏.输沙量对海岸沙丘表面风沙流中不同粒径沙粒垂向分布的影响[J].中山大学学报（自然科学版）,2009,48(3):102-108.

[8]Zou X Y,Hao Q Z,Zhang C L,et al.Analysis of trajectory parameters of salatation grains in sand flow[J].Chinese Science Bulletin,1999,44(18):1681-1685.

[9]Hesse P P,Simpson R L.Variable vegetation cover and episodic sand movement on longitudinal desert sand dunes[J].Geomorphology,2006,81:276-291.

[10]Huang N,Zhen X J.A laboratory test of the electrification phenomenon in wind-blown sand flux[J].Chinese Science Bulletin,2001,46(5):417-420.

[11]邹学勇,董光荣,王周龙.戈壁风沙流若干特征研究[J].中国沙漠,195,15(4):368-373.

[12]屈建军,黄宁,拓万全,等.戈壁风沙流结构特征及其意义[J].地球科学进展,2005,20(1):19-23.

[13]Bagnold R A.The Physics of Blown Sand and Desert Dunes[M].London:Methuen,1941:68-70.

[14]Owen P R.Saltation of uniform grains in air[J].Journal of Fluid Mechanics,1964,20:225-242.

[15]Dong Z B,Qu J J,Liu X P,et al.Experimental investigation of the drag coefficients of gobi surfaces[J].Science in China(Series D),2002,45(7):609-615.

[16]刘小平,董治宝.空气动力学粗糙度的物理与实践意义[J].中国沙漠,2003,23(4):337-346.

[17]马士龙,丁国栋,罗俊宝,等.固定裸沙地粗糙度动力学特征的分析与研究[J].水土保持研究,2005,12(5):218-220.

[18]刘小平,董治宝,王训明.固定沙质床面的动力学粗糙度[J].中国沙漠,2003,23(2):111-117.

[19]董治宝,孙宏义,赵爱国.WITSEG集沙仪:风洞用多路集沙仪[J].中国沙漠,2003,23(6):714-720.

[20]丁国栋,奥村武信.风沙流结构的风洞实验研究[J].内蒙古林学院学报,1994,16(1):40-46.

[21]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,1981:56-60.

[22]王训明,董治宝,陈广庭.塔克拉玛干沙漠中部部分地区风沙环境特征[J].中国沙漠,2001,21(1):56-61.