Nonpoint source pollution has gradually received attention during stormwater flush in highway runoff. The understanding the pollutant characteristics will be criticat issue to treat these types of pollution. In the pr...Nonpoint source pollution has gradually received attention during stormwater flush in highway runoff. The understanding the pollutant characteristics will be criticat issue to treat these types of pollution. In the present study, two monitoring stations were selected to measure hydrology and to take sampling during first flushing events at the Zhong-Shan freeway and East-West expressway in the Miaoli County, Taiwan. The results of monitoring stations in 2007 storm events found that normally the peak concentrations of total suspended solids （TSS） and heavy metals occurred at the initial stormwater and then the concentrations decreased when the measured time elapsed. The highest and lowest heavy metal concentrations were Fe and Ni, respectively, during the stormwater. Particle size distribution （PSD） mostly ranged from 12μm and 96 μm at two measured sites. The event mean concentrations （EMCs） and loadings of TSS and heavy metals were also correlated with total runoff and total rainfall.展开更多
This paper presents a novel numerical model using a fully three-dimensional(3D),incompressible,two-phase flow NavierStokes(NS)solver,which are discretized by the finite volume method.A high-resolution STACS-VOF method...This paper presents a novel numerical model using a fully three-dimensional(3D),incompressible,two-phase flow NavierStokes(NS)solver,which are discretized by the finite volume method.A high-resolution STACS-VOF method is used to capture the interface between the air and water phases.The validity of the simulation following this model is examined through3D shear flow and collapsing cylinder of water.Then,this proposed model is adopted to simulate the dynamics of flow involved with surge bore propagating over a slope in the swash zone.The computed uprush shoreline motion and the tip of runup water surface agreed well with experimental data,which indicates that this model can describe the aerated flow accurately.Numerical analyses are also applied to the spatial and temporal distributions of free-surface,instantaneous flow field,and maximal bed shear stress in the bore collapse,uprush and backwash processes.The results from the analyses reveal that the flow dynamics is complicated after the bore breaks,and the proposed model can well capture the structure characteristics of sheet flow,which are better than the previous results.All these findings are of help to understand the pattern of sediment transport and coastal evolution in the swash zone.展开更多
文摘Nonpoint source pollution has gradually received attention during stormwater flush in highway runoff. The understanding the pollutant characteristics will be criticat issue to treat these types of pollution. In the present study, two monitoring stations were selected to measure hydrology and to take sampling during first flushing events at the Zhong-Shan freeway and East-West expressway in the Miaoli County, Taiwan. The results of monitoring stations in 2007 storm events found that normally the peak concentrations of total suspended solids （TSS） and heavy metals occurred at the initial stormwater and then the concentrations decreased when the measured time elapsed. The highest and lowest heavy metal concentrations were Fe and Ni, respectively, during the stormwater. Particle size distribution （PSD） mostly ranged from 12μm and 96 μm at two measured sites. The event mean concentrations （EMCs） and loadings of TSS and heavy metals were also correlated with total runoff and total rainfall.
基金supported by the National Natural Science Foundation of China(Grant Nos.51239001,51179015,41176072)
文摘This paper presents a novel numerical model using a fully three-dimensional(3D),incompressible,two-phase flow NavierStokes(NS)solver,which are discretized by the finite volume method.A high-resolution STACS-VOF method is used to capture the interface between the air and water phases.The validity of the simulation following this model is examined through3D shear flow and collapsing cylinder of water.Then,this proposed model is adopted to simulate the dynamics of flow involved with surge bore propagating over a slope in the swash zone.The computed uprush shoreline motion and the tip of runup water surface agreed well with experimental data,which indicates that this model can describe the aerated flow accurately.Numerical analyses are also applied to the spatial and temporal distributions of free-surface,instantaneous flow field,and maximal bed shear stress in the bore collapse,uprush and backwash processes.The results from the analyses reveal that the flow dynamics is complicated after the bore breaks,and the proposed model can well capture the structure characteristics of sheet flow,which are better than the previous results.All these findings are of help to understand the pattern of sediment transport and coastal evolution in the swash zone.
