摘要
通过风洞模拟试验,测定了3种配置仿真防护林带的水平与垂直方向风速变化,分析其防风效能。结果表明:2种非均匀配置防护林带风速降低的观测点分别为84.61%和82.00%,而均匀结构防护林风速降低的测点只有74.61%。在水平方向,非均匀结构防护林的前高后低型配置的林带风速降低最大区域出现在林带后树高的2~4倍和林带前1.5~2倍树高范围,有2个风速明显降低区;前低后高型仿真防护林则在树高的1~2倍,而均匀结构林带的风速降低区在林带后树高的4~5倍范围。在垂直方向,前高后低型林带的风速降低最大区域为树高0.5~1倍树高范围,前低后高型林带的风速降低最大区域在0.5~0.75倍树高范围,均匀型林带的风速降低率较大区域高度为0.75~1倍树高范围。防护林组成前高(3行)后低(3行)非均匀配置防护林的防风效能相对均匀结构较大,是一种相对较优的防护林配置模式。
Through the wind tunnel simulation experiments,the horizontal&vertical wind speed changes of simulated shelter belts with three kinds of arrangements were measured,and their wind speed reduction effects was analyzed.Result shows that the observation points of the wind speed reduction of the two nonuniform arrangements shelter belts are 84.61%&82.00%,respectivety,while that of the uniform arrangements shelterbelt is only 74.61%.In the horizontal direction,the maximum reduction area of wind speed in the front high and back low shelterbelt of protection forest with ununiform structure is 2-4 times and 1.5-2 times of the simulation tree height behind and front the shelterbelt,which means there were two wind speed reduction areas.The wind speed reduction zone of the front low and back high simulation protection forest is 1-2 times the tree height behind the shelterbelt.The reduction area of wind speed in uniform configuration shelterbelt was five times of the simulation tree height behind the shelterbelt.In the vertical direction,the reduction rate of wind speed in the front high and back low type of shelterbelt is about 0.5-1 times of the simulation tree height.The reduction rate of wind speed in the front low and back high type of shelterbelt is 0.75 times of the simulation tree height.The reduction rate of wind speed in the uniform type of shelterbelt is 0.75-1 times of the simulation tree height.The windbreak efficiency of the shelterbelt with three rows high tree at front position and three rows later low at rear position of non-uniform configuration of the shelterbelt is relatively large,which is a relatively optimal shelter forest structure.
作者
李亚琦
马瑞
刘虎俊
刘淑娟
万翔
刘开琳
李菁菁
李学敏
Li Yaqi;Ma Rui;Liu Hujun;Liu Shujuan;Wan Xiang;Liu Kailin;Li Jingjing;Li Xuemin(Gansu Agriculture University,Lanzhou 730070,China;Desert Control Research Institute,Lanzhou 730070,China)
出处
《防护林科技》
2020年第3期1-4,18,共5页
Protection Forest Science and Technology
基金
甘肃省重大专题项目:风沙区精准治沙关键技术研究与示范(18ZD2FA009)
甘肃省林草局项目:低覆盖度非均匀配置防风固沙林防护效益的风洞实验研究.
关键词
防护林配置
非均匀
风速
防风效能
风洞模拟实验
arrangement of protection forest
nonuniform
wind speed
wind speed reduction effects
wind tunnel simulation experiment
