基于Delft3D模型的近海水环境质量数值模拟研究

Study on numerical simulation of environmental quality in coastal water based on Delft3D model

以天津市近岸海域为例,基于Delft3D数学模型,开展了近海水环境质量数值模拟研究。首先,采用Delft3D模型中的Grid模块对研究海域进行网格划分和地形处理;然后,以5个主要陆源入海河口的排污数据作为模拟模型闭边界取值,并根据实测资料设定模型的开边界条件及模型参数;最后,采用Delft3D模型中的水动力模块Flow和水质模块Waq,对5个陆源入海河口处的示踪浮子运动轨迹及近海流场、水质变化规律进行了模拟研究。模拟结果表明:天津市近岸海域的流场基本可分为大沽口以南的逆时针流场和大沽口以北的顺时针流场两大区域,在该流场的驱动下,不同陆源入海河口处排放的污染物有着较为规律的运动轨迹和相应的影响范围,表现出明显的区域性污染特征,模拟分析结果与天津市近岸海域实际情况基本一致,可为天津市近海水环境的区域化管理提供决策支持。

Taking the coast of Tianjin as an example, the wate~ environmental quality was simulated based on Delft3 D model. Firstly, the study area was divided into grids by the Grid module of Delft3 D model. Secondly, the pollutant emissions data of five outfalls was valued as the closed boundary conditions of the simulation model, and the open boundary conditions and model parameters were deter- mined according to the actual data. Finally, the coastal flow, float＇s transfer locus and water environmental quality were simulated by the Flow and Waq modules of Delft3D model. The simulation results showed that the flow of Tianjin＇s coast was divided into two parts, and the pollutant distributions of five outfalls has the regional characteristics obviously. The results were matched with the actual situa-tion of Tianjin＇s coast, and could be used to supply the decision support for the regional management of coastal water.