Impact factors of fractal analysis of porous structure

Abstract

Characterization of pore structure is one of the key problems for fabrication and application research on porous materials. But, complexity of pore structure makes it difficult to characterize pore structure by Euclidean geometry and traditional experimental methods. Fractal theory has been proved effective to characterize the complex pore structure. The box dimension method based on fractal theory was applied to characterizing the pore structure of fiber porous materials by analyzing the electronic scanning microscope (SEM) images of the porous materials in this paper. The influences of image resolution, threshold value, and image magnification on fractal analysis were investigated. The results indicate that such factors greatly affect fractal analysis process and results. The appropriate magnification threshold and fractal analysis are necessary for fractal analysis. porous materials, fractal dimension, porous structure Citation: Tang H P, Zhu J L, Xi Z P, et al. Impact factors of fractal analysis of porous structure.Pore structure is one of the most important factors for applied performance of porous materials. Many behaviors of porous materials, such as sound absorption, diffusion, permeability and mechanical properties, depend on the pore structure. Therefore, describing the pore structure properties of porous materials is a worldwide topic. Large number of studies show that porous materials have typical fractal features [1]. It is feasible to investigate pore structure and the relationship between performances and characters of pore structure by fractal theory. The accuracy of fractal analysis depends on the fractal object selected and fractal analysis process. There are many factors which may influence the analysis process for the fractal analysis method based on two-dimensional digital images, such as methods to obtain binary images, image resolution, image magnification, and threshold value. Each factor may lead to inaccurate calculation of the fractal dimension. Therefore, it is necessary to investigate the influence factors on fractal analysis process. Fractal box dimensions were calculated in this paper, and the influences of image resolution, threshold value, and image magnification on fractal analysis were investigated.

Multifractal analysis of gas adsorption isotherms for pore structure characterization of the Bakken Shale

“…It is well understood that pore size in shales is not uniformly distributed thus cannot be represented by traditional Euclidean geometry [23][24][25]. Thus, in order to describe the complexity that exists in pore structures, fractal theory, initially proposed by Mandelbrot [26], has been widely used instead.…”

Nanopore structure comparison between shale oil and shale gas: examples from the Bakken and Longmaxi Formations

“…The fractal theory is a very practical tool to characterize the overall structure of the pore network in any porous medium. Through this method, we can extract the fractal dimensions from the dataset and then describe the selfsimilar geometric irregularities of the pore space at different scales (Tang et al 2010). In this study, the multifractal method was employed to analyze and compare the pore structures of the samples from the Longmaxi and Bakken Formations.…”

Review on Fractal Analysis of Porous Metal Materials

“…The fractal dimension of pore structure of porous metal materials was affected by the porosity, the image magnification, the powder particle size, the powder morphology, the image resolution, and the image region chosen [22][23][24][25][26][27].…”

“…The fractal dimension is also influenced by the image resolution, shown in Figure 4 [26,27]. It can be seen from Figure 4 that the fractal dimension at the original image resolution is Figure 4: Fractal dimension versus image resolution for porous metal fiber materials.…”

“…For porous metal material, its performance is strongly affected by the pore structure, so the accurate description of pore structure has become a research hotspot in recent years [19]. The fractal theory is an effective method for discussing the pore structure of porous metal materials.…”