Department of Environmental Science and Technology, Faculty of Science and Technology, Meijo University, Tenpaku-ku, Nagoya, Aichi, Japan.
J Contam Hydrol. 2012 Apr 1;131(1-4):39-53. doi: 10.1016/j.jconhyd.2012.01.003. Epub 2012 Jan 20.
In a previous study, column experiments were carried out with Toyoura sand (permeability 2.05×10(-11)m(2)) and Toyoura sand mixed with bentonite (permeability 9.96×10(-13)m(2)) to obtain the molecular diffusion coefficient, the Knudsen diffusion coefficient, the tortuosity for the molecular diffusion coefficient, and the mechanical dispersion coefficient of soil-gas systems. In this study, we conducted column experiments with field soil (permeability 2.0×10(-13)m(2)) and showed that the above parameters can be obtained for both less-permeable and more-permeable soils by using the proposed method for obtaining the parameters and performing column experiments. We then estimated dispersivity from the mechanical dispersion coefficients obtained by the column experiments. We found that the dispersivity depended on the mole fraction of the tracer gas and could be represented by a quadratic equation.
在之前的研究中，使用户冢砂（渗透率为 2.05×10(-11)m(2)) 和户冢砂与膨润土的混合物（渗透率为 9.96×10(-13)m(2)) 进行了柱实验，以获得分子扩散系数、克努森扩散系数、分子扩散系数的曲折度和土壤气体系统的机械弥散系数。在这项研究中，我们使用现场土壤（渗透率为 2.0×10(-13)m(2)) 进行了柱实验，并表明可以通过使用提出的获取参数和进行柱实验的方法，获得两种渗透率更低和更高的土壤的上述参数。然后，我们从柱实验获得的机械弥散系数估计了弥散度。我们发现，弥散度取决于示踪气体的摩尔分数，可以用二次方程表示。
