Fractal characteristic of virtual fibrous porous media

Abstract

Fractal theory is a very effective method for investigating pore-structure of fibrous porous materials, which build a bridge between micro-morphology and macro-performance. Fractal dimension was calculated based on the fractal theory and combined with computer virtual building model technology, which was explored to describe the pore structure of virtual fibrous porous materials. The geometric model construction program was completed to generate virtual filter media which has straight fiber and bending fiber. These fibers are randomly distributed in two directions or three directions. A variety of virtual fibrous media were used to calculate packing density or porosity and fractal dimension. The fractal dimension of 2D or 3D pore structure was calculated by the soft and the effects of packing density or porosity on fractal dimension were also discussed. Fractal dimension of the two-dimensional cross-sectional view, plan view or section view has the same form of expression, their coefficients was different with the variation in position observations. The results show that the fractal dimension decreases continuously with the increase of fiber diameter, but it increases gradually with the packing density increasing. Furthermore, the relationships between the fractal dimension and the fiber diameter and packing density were obtained.