非饱和-饱和区域中重金属污染物运移数值模拟

Numerical analog simulation of heavy metal pollution transport in variably saturated flow

为了定量整体描述非饱和-饱和区域内水流及溶质迁移过程,在基于非饱和流动理论及溶质运移理论基础上,建立了非饱和-饱和区域内水流方程与重金属污染物运移方程耦合的数学模型。采用V-G模型来描述土壤水分特征函数.用Lagrange-Quadratic方法进行求解并给出模拟结果:分析结果表明,在非饱和-饱和区域内的压力水头、饱和度以及污染物阻滞因子等参数均随含水率的变化而改变,这是区别于饱和流的主要特点。

According to theory of the unsaturated flow and solute transport,the mathematical model of the groundwater flow equation coupled with the heavy mental pollution transport equation is established.The Van Genuchten model is used to describe the soil water retention function,and solve this coupling model with the Lagrange-Quadratic method.The conclusion is drawn from the analysis of the simulation results in variably saturated domain that the pressure head,effective saturation of the soil and the retardation factor vary with the infiltration of the water.This is main feature different from the saturated flow.