摘要
污染物在黏土防渗层中扩散时,不仅需考虑污染物离子自身活性,还须考虑黏土介质自身带负电特性这一离子存在环境对扩散进程的影响。通过对电场作用下的活度系数进行修正并引入电化学势描述方程,建立了适用于带电性黏土介质的基于动量平衡的多离子体系扩散模型。由于所建模型的复杂性,选用多物理场仿真软件COMSOL Multiphysics开展数值模拟,揭示了多离子体系在黏土垫层中的运动规律。数值结果表明:随着污染物离子初始浓度的增大,考虑土体带电特性及离子活性对扩散进程的阻滞效果越来越明显。
When the contaminant diffuses in the clay impermeable layer, it is necessary to study not only the activity of the contaminant ions, but also the influence of clay materials carried with negative charge on the diffusion process of contaminant ions. In this study the activity coefficient was modified under the action of electric field and the electrochemical potential description equation was introduced, finally a multi-ion system diffusion model for charged clay media was proposed based on momentum balance. The finite element software COMSOL Multiphysics was used to conduct numerical simulation to reveal the motion law of multi-ion system in clay liner. The numerical results show that the block effects considering charged clay and ions activity on diffusion process become more and more obvious with the increase of initial concentration of contaminant ions.
作者
张志红
巨占莹
田改垒
郭飞
ZHANG Zhihong;JU Zhanying;TIAN Gailei;GUO Fei(College of Architecture and Civil Engineering,Beijing University of Technology,Beijing 100124,Chin;Beijing Municipal Construction Co.,Ltd.,Beijing 100048,China)
出处
《水利与建筑工程学报》
2019年第1期13-18,共6页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金面上项目(51678012)
关键词
多离子体系
扩散
活度
动量平衡
黏土
multi-ions system
diffusion
activity
momentum balance
clay soil
作者简介
张志红(1976-),女,河北深州人,副教授,主要从事环境岩土工程方面的研究工作.E-mail:zhangzh2002@126.com.
