Numerical modelling of hydro-morphological processes dominated by fine suspended sediment in a stormwater pond

JOURNAL OF HYDROLOGY

卷:556

Article

Guan, Mingfu¹  Ahilan, Sangaralingam^2,5,6  Yu, Dapeng¹  Peng, Yong^3,7  Wright, Nigel⁴ 

[1] Loughborough Univ, Dept Geog, Loughborough, Leics, England

[2] Univ Exeter, Ctr Water Syst, Exeter, Devon, England

[3] Sichuan Univ, State Key Lab Hydraul & Mt River Engn, Chengdu, Sichuan, Peoples R China

[4] De Montfort Univ, Fac Technol, Leicester, Leics, England

[5] Univ Leeds, Water Leeds, Leeds, W Yorkshire, England

[6] Univ Leeds, Sch Civil Engn, Leeds, W Yorkshire, England

[7] Sichuan Univ, Coll Water Resources & Hydropower, Chengdu, Sichuan, Peoples R China

关键词: Shallow water equations;    Suspended load;    Morphological changes;    Stormwater pond;   

DOI  :  10.1016/j.jhydrol.2017.11.006

来源: Elsevier

【 摘 要 】

Fine sediment plays crucial and multiple roles in the hydrological, ecological and geomorphological functioning of river systems. This study employs a two-dimensional (2D) numerical model to track the hydro morphological processes dominated by fine suspended sediment, including the prediction of sediment concentration in flow bodies, and erosion and deposition caused by sediment transport. The model is governed by 2D full shallow water equations with which an advection diffusion equation for fine sediment is coupled. Bed erosion and sedimentation are updated by a bed deformation model based on local sediment entrainment and settling flux in flow bodies. The model is initially validated with the three laboratory-scale experimental events where suspended load plays a dominant role. Satisfactory simulation results confirm the model's capability in capturing hydro-morphodynamic processes dominated by fine suspended sediment at laboratory-scale. Applications to sedimentation in a stormwater pond are conducted to develop the process-based understanding of fine sediment dynamics over a variety of flow conditions. Urban flows with 5-year, 30-year and 100-year return period and the extreme flood event in 2012 are simulated. The modelled results deliver a step change in understanding fine sediment dynamics in stormwater ponds. The model is capable of quantitatively simulating and qualitatively assessing the performance of a stormwater pond in managing urban water quantity and quality. (C) 2017 The Author(s). Published by Elsevier B.V.

【 授权许可】

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