Longitudinal dispersion coefficients of pollutants in compound channels with vegetated floodplains  

作　　者：Li Gu Xin-xin Zhao Ling-hang Xing Zi-nan Jiao Zu-lin Hua Xiao-dong Liu 

机构地区：[1]Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China [2]National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing 210098, China [3]Nanjing Guohuan Science and Technology Co., Ltd., Nanjing 210001, China [4]Changjiang River Scientific Research Institute, Wuhan 430010, China

出　　处：《Journal of Hydrodynamics》2019年第4期740-749,共10页水动力学研究与进展B辑（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 51739002, 51379058, 51479064 and 51479010);supported by the Fundamental Research Funds for the Central Universities (Grant No. 2016B06714);the PAPD Project and the National Public Research Institutes for Basic R&D Operating Expenses Special Project (Grant No. CKSF2015050/SL).

摘　　要：The characteristics of the longitudinal dispersion of pollutants in compound channels remain unclear. This study examines the relationships among the vegetation density, the width of the floodplain, the water depth ratio, the cross-sectional mean velocity, and the longitudinal dispersion coefficient of a symmetrical compound channel with a rigid non-submerged vegetated floodplain. The longitudinal dispersion coefficient is found to increase significantly with the presence of vegetation on floodplains, and is positively correlated with the plant density. When the density of the vegetation on the floodplains exceeds a certain value, the dispersion coefficient no longer changes with the vegetation density. The longitudinal dispersion coefficient is found to increase with the increase of the width of the floodplain. Moreover, the combined effects of the mean velocity and the water depth ratio have a positive correlation with the dispersion coefficient. The effects of the vegetation on the longitudinal dispersion coefficient in the channels with various cross-sections are also compared. The compound channels with a vegetated floodplain are found to differ significantly from the channels with a rectangular cross-section.

关 键 词：COMPOUND channel longitudinal DISPERSION COEFFICIENT RELATIONSHIP vegetated FLOODPLAIN 

分 类 号：T[一般工业技术]