Spatial Distribution of Transverse Dispersion Coefficients at U-shaped Bend Confluence with 60° Junction Angle

2017 International Conference on Sustainable Development on Energy and Environment Protection

能源学;生态环境科学

Zhao, X.X.^1 ; Gu, L.^1,2 ; Dai, B.^1

Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake, Ministry of Education, College of Environment, Hohai University, Nanjing

210098, China^1

National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing

210098, China^2

关键词: Bend channels;    Dispersion capacity;    Dispersion tensors;    Hydraulic characteristic;    Junction angles;    Peak values;    Three-dimensional numerical modeling;    Transverse dispersion;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/86/1/012011/pdf
DOI  :  10.1088/1755-1315/86/1/012011

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

The confluence of bend channel and the tributary is fairlycommon in nature. At present the study about the dispersion capacity of pollutants in the bend confluence is very limited. In this paper, a three-dimensional numerical model was established to explore the hydraulic characteristics such as velocity distribution and circulation structure of the different sections in the U-shaped bend confluence. Then the transverse dispersion coefficient was calculated using the dispersion tensor method and N-zone model on the base of flow structure data, and its spatial distribution along the bend is analyze. The results show that there is a significant difference in the flow structure of each section at the U-shaped bend confluence, especially before and after the junction of tributary.The peak value location of the transverse dispersion coefficient at the cross section appears near the inner bank. Along the bend channel, the transverse dispersion coefficient tends to increase first and then decrease, and the maximum value of the section appears before the bend apex where the tributary feeding into the main channel.