基于有限体积法的土壤重金属污染物运移模拟

摘要 针对重金属污染物在土壤中的运移扩散问题，采用有限体积法对二维稳态水流中污染物运移的基本方程进行离散，获得污染物在饱和土壤中运移的有限体积法计算模型.运用Matlab模拟不同条件下重金属污染物运移的动态过程，研究污染物运移规律.研究表明，当污染源始终存在时，随着时间的推移，质量浓度等值线近似由中心抛物线形渐变为外围椭圆形，水平向和竖直向浓度均不断减小;当污染源存在10天后移除时，随着时间的推移，质量浓度等值线呈椭圆形，污染范围逐渐变大，浓度不断减小，椭圆中心处浓度最大.
Abstract：Aiming at the migration and diffusion of heavy metal pollutants in soil， the finite volume method is used to discretize the basic equations that heavy metal pollutants transport in two-dimensional steady water flow， and then the calculation model for migration in saturated soil is obtained. The dynamic process of heavy metal pollutants transporting in different conditions is simulated by Matlab to study the migration laws of heavy metal pollutants. The research shows that the concentration contours of heavy metal pollutants gradually changes from central parabolic into peripheral elliptical over time， and concentration decreases continuously in both horizontal and vertical directions， when the source of pollution always exists; however， the concentration contours of heavy metal pollutants mainly presents elliptical over time， and pollution range gradually becomes larger with concentration decreasing continuously and the maximum concentration at the ellipse center， when the source of pollution lasts for only 10 days.