丁坝浑水水流环境下污染物三维数学模型

为分析丁坝附近的冲淤和水流对污染物扩散的影响,用体积比函数方法建立水沙动力学模型,考虑泥沙对污染物动态吸附解吸作用,建立了污染物三维吸附态和溶解态水质模型。数值计算非淹没丁坝附近三维水沙流动,计算结果与试验结果比较表明,所建立的数学模型能准确地模拟丁坝附近的自由水面和流场。污染物在丁坝附近的扩散模拟显示了丁坝后的回流区减慢了污染物浓度的衰减,丁坝附近水流的湍动使得冲淤条件下污染物悬沙吸附量和溶解态浓度明显增大。

3D numerical model for pollutant in sediment-laden flow around groyne

The flow field around groyne is of the 3D characteristic. In order to analyze the influence of the flow field and river bed scouring and silting on the polutant diffusion,the dynamical compressive models of water and suspended sediment are derived with the volume of fluid method. Considering the pollutant's adsorption and desorption actions,the 3D water quality models are established for soluble and absorbable pollutant in sediment flow. With calculation of the 3D flow affecting the non-submerged groyne,the comparison between calculative and experimental data means that the dynamical compressive models can accurately simulate the free surface and the flow field around groyne. The simulation of pollutant difusion around groyne shows that the backflow behind groyne slows the decay of pollutant concentration. The turbulence of water flow around groyne increases soluble concentration and absorptive capacity of the suspended sediment markedly under river bed scouring and silting conditions.