To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC res...To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides.展开更多
EFDC模型是当前广泛使用的三维水环境生态模型,也是美国环保局(USEPA,United States Environmental Protection Agency)推荐使用的模型之一。本文简述了EFDC模型的发展历程和基本原理,并对近5年来,EFDC模型在湖泊和水库环境下,关于水动...EFDC模型是当前广泛使用的三维水环境生态模型,也是美国环保局(USEPA,United States Environmental Protection Agency)推荐使用的模型之一。本文简述了EFDC模型的发展历程和基本原理,并对近5年来,EFDC模型在湖泊和水库环境下,关于水动力、水质及富营养化、沉积物及毒物、环境容量和TMDLs(Total Maximum Daily Loads)计划等方面的主要研究成果进行评述。同时,本文也探讨了当前湖库水环境模拟研究中存在的主要问题,并对其发展趋势和前景进行了展望。展开更多
Based on the Environmental Fluid Dynamics Code(EFDC),a three-dimensional baroclinic model for lower reaches of the Yangtze River,Yangtze River Estuary,Hangzhou Bay and the adjacent sea areas was established with the s...Based on the Environmental Fluid Dynamics Code(EFDC),a three-dimensional baroclinic model for lower reaches of the Yangtze River,Yangtze River Estuary,Hangzhou Bay and the adjacent sea areas was established with the sigma-coordinate in the vertical direction and the orthogonal curvilinear coordinates in the horizontal direction.The fine silt particle tracers were injected during different tides with the calibrated three-dimensional numerical model in the Yangtze River Estuary to simulate the migration tracks of the tracers in the following three days,and thereby study the migration behavior of the fine silt particles of dredged sediment after dumping at different locations in the navigation channel in the Yangtze River Estuary.The study shows that the particle paths of the tracer particles basically migrate to the open sea along the middle axis of river course in the form of reciprocating oscillation,the migration and diffusion directions of tracer particles are basically parallel to the navigation channel in guide levee,similar to long belt distribution,and the tracer particles migrate to the southeast out of the guide levee.The particle which is on the southern and northern sides enter groin and cross the navigation channel in the process of movement,and is easy to deposit in the navigation channel.The migration tracks of the particles released at different layers are basically similar at the same release station,but specifically different,varying at different cross sections.The result can be used for the choice and evaluation of dredging schemes in the Yangtze River Deepwater Navigation Channel.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42176166,41776024).
文摘To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides.
文摘EFDC模型是当前广泛使用的三维水环境生态模型,也是美国环保局(USEPA,United States Environmental Protection Agency)推荐使用的模型之一。本文简述了EFDC模型的发展历程和基本原理,并对近5年来,EFDC模型在湖泊和水库环境下,关于水动力、水质及富营养化、沉积物及毒物、环境容量和TMDLs(Total Maximum Daily Loads)计划等方面的主要研究成果进行评述。同时,本文也探讨了当前湖库水环境模拟研究中存在的主要问题,并对其发展趋势和前景进行了展望。
基金Project supported by the Public Welfare Special Scientific Research Project of China Ministry of Water Resources(Grant No.200701026)the National Natural Science Foundation of China(Grant No.50709007)supported by the Startup Fund of Hohai University(Grant No.40801107)
文摘Based on the Environmental Fluid Dynamics Code(EFDC),a three-dimensional baroclinic model for lower reaches of the Yangtze River,Yangtze River Estuary,Hangzhou Bay and the adjacent sea areas was established with the sigma-coordinate in the vertical direction and the orthogonal curvilinear coordinates in the horizontal direction.The fine silt particle tracers were injected during different tides with the calibrated three-dimensional numerical model in the Yangtze River Estuary to simulate the migration tracks of the tracers in the following three days,and thereby study the migration behavior of the fine silt particles of dredged sediment after dumping at different locations in the navigation channel in the Yangtze River Estuary.The study shows that the particle paths of the tracer particles basically migrate to the open sea along the middle axis of river course in the form of reciprocating oscillation,the migration and diffusion directions of tracer particles are basically parallel to the navigation channel in guide levee,similar to long belt distribution,and the tracer particles migrate to the southeast out of the guide levee.The particle which is on the southern and northern sides enter groin and cross the navigation channel in the process of movement,and is easy to deposit in the navigation channel.The migration tracks of the particles released at different layers are basically similar at the same release station,but specifically different,varying at different cross sections.The result can be used for the choice and evaluation of dredging schemes in the Yangtze River Deepwater Navigation Channel.
