Tortuosity factor for permeant flow through a fractal solid
Tortuosity factor for permeant flow through a fractal solid
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DOI：
10.1063/1.481631
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发表时间：
2000-05
影响因子：
4.4
通讯作者：
Roberto A Garza-Lopez;Lewis Naya;J. J. Kozak-J.
中科院分区：
文献类型：
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作者：
Roberto A Garza-Lopez;Lewis Naya;J. J. Kozak-J.
有限马尔可夫过程的理论被用来计算一个规范化的曲折度的多孔固体具有明确的内部结构，其特征在于由一个互连的网络的串行和并行通道。介绍的模型是基于门格尔海绵，一个对称的分形维数D=ln 20/ln 3。数值上精确的值的平均行走长度的渗透扩散通过这个系统的计算都在存在和不存在的均匀梯度（偏置或外部场）作用于渗透。然后使用走长的比率来明确地定义介质的归一化弯曲度。研究了对渗透物初始空间分布的不同假设，并设计了研究，以便量化一个或多个出口位置的影响。正如预期的那样，弯曲因子取决于系统尺寸，并给出了第一代和第二代Menger海绵的定量结果。我们的计算表明，对于给定的S...
The theory of finite Markov processes is used to calculate a normalized tortuosity for a porous solid with a well-defined internal structure characterized by an interconnected network of serial and parallel channels. The model introduced is based on the Menger sponge, a symmetric fractal set of dimension D=ln 20/ln 3. Numerically exact values of the mean walklength 〈n〉 for a permeant diffusing through this system are calculated both in the presence and absence of a uniform gradient (bias or external field) acting on the permeant. The ratio of walklengths is then used to define unambiguously a normalized tortuosity for the medium. Different assumptions on the initial spatial distribution of the permeant are investigated and the study is designed so that the effects of one or multiple exit sites are quantified. As expected, the tortuosity factor is dependent on system size, and quantitative results are presented for the first- and second-generation Menger sponge. Our calculations document that for a given s...