Analytical modeling of diffusion-limited contamination and decontamination in a two-layer porous medium
Analytical modeling of diffusion-limited contamination and decontamination in a two-layer porous medium
复制标题
DOI：
10.1016/s0309-1708(96)00062-0
复制
发表时间：
1998-04
影响因子：
4.7
通讯作者：
Chongxuan Liu;W. P. Ball
中科院分区：
文献类型：
--
作者：
Chongxuan Liu;W. P. Ball
溶解污染物在多层多孔介质中的扩散是影响自然水环境中污染和修复的重要现象，包括在地下水含水层和受污染底泥中的扩散。给出了任意边界和初始条件下半无限双层多孔介质中溶质扩散的一种新的解析解。利用拉普拉斯域中的格林函数法，结合二项式定理，求出了该问题的解，便于反演回实时域。结果表明，该解形式简单，计算方便，与基于Crank-Nicolson有限差分法的数值计算结果吻合良好。以受污染地下水含水层为例，说明了不同的边界条件和初始条件对多孔介质的污染和去污有很大影响，并说明了扩散模型在法医学意义上的应用。
Diffusion of dissolved contaminants in multilayer porous media is an important phenomenon affecting both contamination and remediation in natural aqueous environments, including diffusion in groundwater aquitards and contaminated bed sediments. This study presents a new analytical solution for solute diffusion in a semi-infinite two-layer porous medium for arbitrary boundary and initial conditions. The solution was obtained by using the Green's function approach in the Laplace domain with the application of the binomial theorem to facilitate inversion back to the real time domain. Results based on this solution were found to be simple both in form and ease of calculation and to be in good agreement with those obtained using numerical calculations based on the Crank-Nicolson finite difference method. Applications of the solution are presented in the context of a contaminated groundwater aquitard to demonstrate how different boundary and initial conditions can greatly affect the contamination and decontamination of porous media, and to illustrate how diffusion modeling might be used in a forensic sense.