Effect of vegetation on flow structure and dispersion in strongly curved channels

• Published in: Journal of hydrodynamics. Series B 2015-04, Vol.27 (2), p.286-291
• Main Author: 李成光 薛万云 槐文信
• Format: Article
• Language: English
• Subjects: curved open channel; Engineering; Engineering Fluid Dynamics; flow velocity; Hydrology/Water Resources; longitudinal dispersion coefficient; Numerical and Computational Physics; Simulation; transverse dispersion coefficient; vegetation; 分散体; 实验数据; 弯曲通道; 植被区; 流动结构; 纵向扩散系数; 纵向离散系数; 速度梯度
• ISSN: 1001-6058; 1878-0342
• DOI: 10.1016/S1001-6058(15)60483-8

The effect of vegetation on the flow structure and the dispersion in a 180 o curved open channel is studied. The Micro ADV is used to measure the flow velocities both in the vegetation cases and the non-vegetation case. It is shown that the velocities in the vegetation area are much smaller than those in the non-vegetation area and a large velocity gradient is generated between the vegetation area and the non-vegetation area. The transverse and longitudinal dispersion coefficients are analyzed based on the experimental data by using the modified N- zone models. It is shown that the effect of the vegetation on the transverse dispersion coefficient is small, involving only changes of a small magnitude, however, since the primary velocities become much more inhomogeneous with the presence of the vegetation, the longitudinal dispersion coefficients are much larger than those in the non-vegetation case.