不同带宽的防风固沙林流场结构及防风效能风洞实验

doi:10.7522/j.issn.1000-694X.2017.00080

摘要/Abstract

摘要： 林带宽度是防风固沙林建植时要考虑的基本参数，研究不同带宽林带的防护效果对防风固沙林配置及构建具有重要的指导意义。通过风洞模拟实验，在7、10、15 m·s^-1风速条件下，对单行一带（Ⅰ型）、三行一带（Ⅱ型）、六行一带（Ⅲ型）和九行一带（Ⅳ型）共4种带宽的林带的迎风面、带中和背风面的风速进行了测定，分析了4种林带的风速流场、风速加速率和防风效果。结果表明：（1）4种林带流场结构和垂直风速变化规律相似，沿来风向均形成了林带上方和迎风面林缘附近的小范围高风速区及其后的风影区相互组合的流场结构；依据风速垂直变化规律划分为上部变化层（高度30~60 cm，受林带的影响最小）、中间变化层（高度5~20 cm，风速受林冠遮蔽作用，影响最大，且为风影区形成层）和近床面变化层（高度1~3 cm）。（2）4种林带在垂直纵剖面上的平均风速加速率随林带宽度的增大而减小，即Ⅰ型（0.90） > Ⅱ型（0.87） > Ⅲ型（0.79） > Ⅳ型（0.78）。（3）4种林带的防风效果为Ⅰ型和Ⅱ型林带相同，Ⅲ型和Ⅳ型林带相同，后2种林带的防风效果优于前2种林带，且4种林带的防风效能均随着风速的增大而减小。

关键词: 风洞实验, 林带宽度, 流场结构, 风速加速率, 防风效能

Abstract: The width of shelterbelt is the basic parameter to be considered at building the windbreak and sandbreak forest. It has important directive significance to study the protective effect of different width of shelterbelt on the configuration and construction of the windbreak and sandbreak forest. In order to compare the wind speed field, wind speed acceleration and windbreak effect of shelterbelt in different width. We studied the change of the vertical space wind velocities in the condition of 7, 10 and 15 m·s^-1 under the wind tunnel. The result showed that:(1) Four kinds of shelterbelt have similarity in the flow field structure and the change of vertical wind speed. It was found that four kinds of forest belt formed flow field structure which was combined by the high wind speed area and the wind shadow; We divided the vertical space into three layers according to the change of vertical wind speed:upper change layer (30-60 cm, it was least affected by the forest), the middle change layer (5-20 cm, it was the greatest affected by the forest) and near bed surface change layer (1-3 cm). (2) The acceleration rate of wind velocity decreased with the increase of the width of shelterbelt. It is typeⅠ > typeⅡ > typeⅢ > typeⅣ. (3) The windbreak effect of the four kinds of forest belts is the same typeⅠand typeⅡ, the same typeⅢ and typeⅣ. The windbreak effect of the latter two kinds of forest belts was higher than the former two kinds of forest belts. The windbreak efficiency of the four forest belts decreased with the increase of wind speed.

Key words: wind tunnel test, shelterbelt width, flow field structure, wind speed acceleration, windbreak efficiency

中图分类号:

X169

李雪琳, 马彦军, 马瑞, 张莹花, 唐卫东, 杨进杰. 不同带宽的防风固沙林流场结构及防风效能风洞实验[J]. 中国沙漠, 2018, 38(5): 936-944.

Li Xuelin, Ma Yanjun, Ma Rui, Zhang Yinghua, Tang Weidong, Yang Jinjie. Wind Flow Field and Windproof Efficiency of Shelterbelt in Different Width[J]. Journal of Desert Research, 2018, 38(5): 936-944.

参考文献

[1] 马瑞,王继和,屈建军,等.1960-2005年民勤典型绿洲-荒漠过渡带景观格局与动态[J].应用生态学报,2010,21(3):714-722.
[2] 包岩峰.基于流场分析的绿洲防护林防风效果研究[D].北京:北京林业大学,2015.
[3] 杨红艳,王晶莹,杨文斌.行带式柠条林合理带间距的研究[J].干旱区资源与环境,2005,19(7):210-214.
[4] 高尚武.治沙造林学[M].北京:中国林业出版社,1984:34-46.
[5] 杨文斌,卢琦,吴波,等.低覆盖度不同配置灌丛内风流结构与防风效果的风洞实验[J].中国沙漠,2007,27(5):791-796.
[6] 杨文斌,王晶莹.干旱、半干旱区人工林边行水分利用特征与优化配置结构研究[J].林业科学,2004,40(5):3-9.
[7] 杨文斌,赵爱国,王晶莹,等.低覆盖度沙蒿群丛的水平配置结构与防风固沙效果研究[J].中国沙漠,2006,26(1):108-112.
[8] 凌裕泉,屈建军,金炯.稀疏天然植被对输沙量的影响[J].中国沙漠,2003,23(1):14-19.
[9] 杨文斌,冯伟,李卫.低覆盖度治沙的原理与模式[J].防护林科技,2016(4):1-5.
[10] 杨文斌,王涛,冯伟,等.低覆盖度治沙理论及其在干旱半干旱区的应用[J].干旱区资源与环境,2017,31(1):1-5.
[11] 杨文斌,董慧龙,卢琦,等.低覆盖度固沙林的乔木分布格局与防风效果[J].生态学报,2011,31(17):5000-5008.
[12] 徐立帅,穆桂金,孙琳,任晓,周杰.防护林疏透度对近地层大气降尘的影响——以新疆策勒为例[J].中国沙漠,2017,37(1):57-64.
[13] 姜凤岐,朱教君,周新华.林带连续性经济效益模型及其应用的研究[J].林业科学,1999,35(1):11-16.
[14] Zhou X H,Brandle J R,Takle E S,et al. Estimation of the three-dimensional aerodynamic structure of a green ash shelterbelt[J].Agricultural and Forest Meteorology,2002,111(2):93-108.
[15] 朱教君,姜凤岐,范志平,等.林带空间配置与布局优化研究[J].应用生态学报,2003,14(8):1205-1212.
[16] 高函,吴斌,张宇清,等.行带式配置柠条林防风效益风洞试验研究[J].水土保持学报,2010,24(4):44-47.
[17] 刘虎俊.仿真固沙灌木构型参数及防风固沙效应研究[D].兰州:甘肃农业大学,2012.
[18] 罗万银.直立阻沙栅栏二次流特征的风洞模拟实验[D].北京:中国科学院研究生院,2007.
[19] 付亚星,王乐,彭帅,等.河北坝上农田防护林防风效能及类型配置研究——以河北省康保县为例[J].水土保持研究,2014,21(3):279-283.
[20] Vigiak O,Sterk G,Warren A,et al.Spatial modeling of wind speed around windbreaks[J].Catena,2003,52(3/4):273-288.
[21] 彭帅.河北坝上农田防护林带结构配置及防护效益研究[D].石家庄:河北师范大学,2015.
[22] Ma R,Wang J,Qu J,et al.Effectiveness of shelterbelt with a non-uniform density distribution[J].Journal of Wind Engineering and Industrial Aerodynamics,2010,98(12):767-771.
[23] 张莹花,康才周,刘世增,等.沙地云杉(Picea mongolica)农田防护林带不同配置模式的防风效果[J].中国沙漠,2017,37(5):859-866.
[24] 袁鑫鑫,王海峰,雷加强,等.不同间距双排尼龙阻沙网防风效应的风洞模拟[J].中国沙漠,2016,36(5):1238-1246.
[25] 董慧龙,杨文斌,王林和,等.单一行带式乔木固沙林内风速流场和防风效果风洞实验[J].干旱区资源与环境,2009,23(7):110-116.
[26] 朱廷曜,关德新.农田防护林生态工程学[M].北京:中国林业出版社,2000.
[27] 唐玉龙,安志山,张克存,等.不同结构单排林带防风效应的风洞模拟[J].中国沙漠,2012,32(3):647-654.