摘要
通过对戈壁、流沙地表风沙流特性的风洞模拟实验研究,风沙流中的风速廓线分布满足幂函数的形式,其幂指数在0.20左右。对于戈壁地表,在不同风速下,相同高度层含沙量具有很大的相关性,风沙活动层主要集中在距地表20cm范围内;由于沙粒与戈壁地表的砾石发生碰撞,风沙流不再服从对数关系递减,其极值出现的高度随风速的增加而上移,呈现"象鼻效应"。
The characteristics of sand - driving wind over Gobi / mobile sand surface have been investigated experimentally in the wind tunnel. It was found that for a given condition of underlying surface, pattern of wind velocity profile in sand flow conforms to the form of power function u^- = az^b and its power exponent is about 0.20. Sand contents under different wind conditions in the same height show a good correlation over Gobi surface, and the sand activities mainly focus on the range of 0 - 20cm above surface. Due to collision of sand grain with gravels on Gobi surface, the structure of sand flow does not increases logarithmically with height above the surface, and the height with the maximum value of sand content rises as wind velocity add.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2008年第10期55-59,共5页
Journal of Arid Land Resources and Environment
基金
干旱气象科学研究基金(IAM200606)
国家自然科学基金(40701171)项目共同资助
关键词
下垫面
风沙流结构
风速廓线
underlying surface
structure of sand flow
wind velocity profile
