The structure of turbulent flow through submerged flexible vegetation
[浏览次数:1521 ] [更新时间:2019-5-18]
作者
Wen-xin Huai, Jiao Zhang, Gabriel G Katul, Yong-guang Cheng, Xue Tang, Wei-jie Wang
发表日期
2019
期刊
Journal of Hydrodynamics
页码范围
1-19
出版商
Springer Singapore
简介
The hydrodynamics of turbulent flow through submerged flexible vegetation is investigated in a flume using acoustic Doppler velocimetery (ADV) measurements. The flow characteristics such as the energetics and momentum transfer derived from conventional spectral and quadrant analyses are considered as the flow encounters a finite vegetation patch. Consistent with numerous canopy flow experiments, a shear layer and coherent vortex structures near the canopy top emerge caused by Kelvin–Helmholtz instabilities after the flow equilibrates with the vegetated layer. These instabilities are commonly attributed to velocity differences between non-vegetated and vegetated canopy layers in agreement with numerous experiments and simulations conducted on dense rigid canopies. The power-spectral density function for vertical velocity turbulent fluctuations at different downstream positions starting from the …