颗粒孔结构的积木分形模型

Fractal Model of Building Blocks for Pore Structure of Particles

构造了立方和四面体两种积木分形体,得到一般积木分形体模型,导出关联表面积和体积增量的3个分形表达式,并分析了表面分数维的几何意义. 实验结果表明,利用该模型的表面积与体积增量分形表达式可以从压汞和BET的实验数据计算表面分数维,相关系数较高. 对同一种颗粒,两种实验方法可以得到相同的分数维. 讨论了体积增量的计算方法.

Two fractal bodies of building blocks, cube and tetrahedron were structured and a general building blocks model was obtained, from which three fractal equations on surface area, volume increment, and their interrelation were derived to describe the pore structure of porous particles. The experimental results show that surface fractal dimension can be calculated from the data measured experimentally by mercury porosimetry or the BET method using the fractal equation on surface area and volume increment. The same value of fractal dimension can be obtained from the two methods for certain kind of porous particles. The geometrical meaning of surface fractal dimension and the calculation method of volume increment were also discussed.