Submerged rigid vegetation effects on flow hydrodynamics within the pool morphology  

作　　者：Kourosh Nosrati Hossein Afzalimehr Hamidreza Raeisifar Mohammad Nazari-Sharabian Moses Karakouzian 

机构地区：[1]Faculty of Civil Engineering,Iran University of Science and Technology,Tehran,Iran [2]Department of Mathematics,Engineering,and Computer Science,West Virginia State University,Institute,West Virginia,USA [3]Department of Civil and Environmental Engineering,University of Nevada Las Vegas,Las Vegas,Nevada,USA

出　　处：《River》2024年第3期260-271,共12页江河(英文)

摘　　要：This research is centered on a comprehensive investigation into the impact of turbulence on the movement and dispersion of materials within a three-dimensional(3D)bedform,specifically when there is a continuous presence of rigid vegetation submerged in theflow.To achieve our research objectives,we conducted extensive velocity measurements within a channel featuring this submerged vegetation.The measurements were carried out using an Acoustic Doppler Velocimeter(ADV).Additionally,our study delved into the intricate structures and turbulent characteristics of theflow,considering the coexistence of submerged vegetation and a 3D gravel pool.This pool featured entrance and exit slopes measuring 3 and 2.5°,respectively.Our experimental setup took place in a straightflume,measuring 14 m in length,0.9 m in width,and 0.6 m in depth.Theflume was equipped with transparent side walls to facilitate observations.Furthermore,our investigation extended to the spatial variations in velocity and turbulence distributions.We analyzed various parameters including turbulence kinetic energy,integral turbulence lengths,dispersion coefficients,and advective transport.The results revealed that integral length scales offer key insights into turbulent eddy behavior.In the presence of vegetation and a 3D bedform,turbulent eddies undergo notable changes,flattening in the longitudinal direction and expanding in the transverse and vertical directions.Moreover,longitudinal advection is notably higher compared toflows without vegetation in a uniformflow or bare channel,especially for z/H>0.2.This indicates that the presence of vegetation and a 3D bedform leads to an increase in turbulent kinetic energy(k values)that surpasses the reduction in the time-averaged velocity component(“U”)in the U×k term,thereby enhancing longitudinal advection.

关 键 词：3D pool advection dispersion integral turbulent length submerged rigid vegetation 

分 类 号：O35[理学—流体力学]