【作者】 程鹏达； 林卫青； 卢士强； 王道增；

【Author】 CHENG Peng-da~1,LIN Wei-qing~2,LU Shi-qiang~2,WANG Dao-zeng~2 (1.Shanghai Institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai 200072,2.Shanghai Academy of Environmental Sciences,Shanghai,200233 China)

【机构】 上海市应用数学和力学研究所,上海大学； 上海市环境科学研究院；

【摘要】 环境水动力学中,湖库底泥污染物释放是人们研究的主要问题之一。不同水动力学条件下污染物会通过颗粒孔隙水重新释放到上覆水体中形成二次污染,释放机制大致可分为吸附解吸、分子扩散和对流扩散。本文中以溶解态无机磷（P）代表典型吸附性污染物,改变底泥颗粒粒径和水力条件,对P释放过程进行了理论分析,建立P释放过程的耦合数学模型,并进行验证实验,分析吸附解吸、分子扩散和对流扩散在P释放过程中的作用。初步确定粒径D₉₀为0.06 mm时,泥沙物理特性对P释放影响较大。此外确定静态泥沙在动水条件下泥水界面存在扩散边界层,扩散边界层内的对流扩散、分子扩散以及吸附解吸分别对P的释放有规律性的影响。更多还原

【Abstract】 Contaminant release from bottom sediments in rivers is one of the main problems to study the environmental hydrodynamics.Contaminant will release into the overlying water column under different hydrodynamic conditions through pore-water in sediment,the release mechanism can be roughly divided into convection diffusion,molecular diffusion and adsorption/desorption.In this article,dissolving inorganic phosphorus was as a typical contaminant with sorption.Through theoretical analysis of the contaminant release,according to different particle-sized and hydraulic conditions, the mathematics model of contaminant release can be established by the coupled N-S equation, Darcy equation,solute transport equation and adsorption/desorption equation.Then that model was verified by flume experiment.Through analysis,the environment effect of sediment will be influenced much more by the size change when the particle size is relatively small under different velocity, and the environment effect is more obvious,when the D₉₀ of fine sediment is 0.06mm.In addition, that release mechanism mainly exist in the diffusive boundary layer below the interface.更多还原