平行大理石板裂隙污染物运移实验与连续时间随机游走模拟  

Experiments and model on contaminant transport in a single marble parallel plate fracture using continuous time random walk

作　　者：郑志成 刘咏[2] 王沐[1] 李福林[3] 黄继文[3] ZHENG Zhicheng;LIU Yong;WANG Mu;LI Fulin;HUANG Jiwen(School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, China;School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, China;Shandong Academy of Water Conservancy, Jinan 250013, China)

机构地区：[1]合肥工业大学资源与环境工程学院,安徽合肥230009 [2]合肥工业大学食品与生物工程学院,安徽合肥230009 [3]山东省水利科学研究院,山东济南250013

出　　处：《合肥工业大学学报（自然科学版）》2019年第5期677-682,共6页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金资助项目(41372245;41641021);山东省科技支撑计划资助项目(SSTWMZCJH-SD04)

摘　　要：单个裂隙是构成裂隙网络的基础,其中的水流和溶质运移机理目前尚未完全清楚。文章使用平行大理石板构成单裂隙试验模型,研究了水力梯度和流速之间的关系以及溶质运移规律,采用连续时间随机游走(continuous time random walk,CTRW)模拟软件包中的截断幂函数(truncation power-law function,TPL)对溶质的穿透曲线进行模拟,并与传统的对流-弥散方程(advection-dispersion equation,ADE)模拟结果进行了对比,探讨了CTRW中参数的变化特征。结果表明:实验条件下的水流呈非达西流,用Forchheimer方程能更好地拟合裂隙中水力梯度和流速的关系;裂隙内的溶质运移为非费克运移,表现出明显的“拖尾”现象;在实验条件下拟合溶质运移的穿透曲线,TPL的拟合结果均明显优于ADE;同一隙宽下,模型参数β随流速的增加而增加,其值分别为0.882、1.045、1.375;同一流速下,β随隙宽的增加而减小,其值分别为1.375、1.263、1.112。Single fracture is basic unit of the fracture networks, the mechanism of flow and solute transport in fractured media is still not completely understood. Single marble parallel plate fracture model is established in this study. The relationships between the flow velocity and the hydraulic gradient and the laws of solute transport are studied. The experimental data are simulated using the truncation power-law function(TPL) model in the package of the continuous time random walk(CTRW) and the results are compared with the simulation results using advection-dispersion equation(ADE), and the change of the parameter in the CTRW is discussed. The results indicate that the flow obeys non-Darcian flow in the different experimental conditions, which can be better simulated using the equation of Forchheimer;the solute transport in marble parallel plates presents non-Fickian phenomenon with “long tail”;the fitting results using of TPL model are significantly better than those of ADE in the experimental condition;under the same aperture, the values of model parameter β increase with the increasing velocity, which are 0.882, 1.045, and 1.375, respectively;under the same velocity, the values of β decrease with the increasing aperture, which are 1.375, 1.263 and 1.112, respectively.

关 键 词：大理石平板裂隙 溶质运移 非费克运移 对流-弥散方程(ADE) 连续时间随机游走(CTRW) 

分 类 号：P641.2[天文地球—地质矿产勘探]