Yang RY, Zou RP, Yu AB
School of Materials Science and Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 2000 Sep;62(3 Pt B):3900-8. doi: 10.1103/physreve.62.3900.
This paper presents a simulation study of the packing of uniform fine-spherical particles where the van der Waals force is dominant. It is shown that porosity increases with the decreases of particle size from about 100 to 1 &mgr;m and the simulated relationship can match the literature data well. The packing structure of fine particles is qualitatively depicted by illustrative pictures and quantified in terms of radial distribution function, angular distribution, and coordination number. The results indicate that in line with the increase in porosity, the first component of the split second peak and then the other peaks beyond the second one in the radial distribution function gradually vanish; the first peak becomes narrower, with a sharp decrease to the first minimum. As particle size decreases, the peaks at 120 degrees and then 60 degrees in the angular distribution will gradually vanish; the coordination number distribution shifts to the left and becomes narrower. The mean coordination number can decrease to a value as low as two for 1 &mgr;m particles, giving a very loose and chainlike structure. The interparticle forces acting on individual particles in a stable packing are analyzed and shown to be related to the packing properties.
本文展示了一项关于均匀细球形颗粒堆积的模拟研究，其中范德华力起主导作用。结果表明，当粒径从约100微米减小到1微米时，孔隙率会增加，且模拟关系与文献数据匹配良好。通过示例图片定性地描绘了细颗粒的堆积结构，并根据径向分布函数、角分布和配位数进行了量化。结果表明，随着孔隙率的增加，径向分布函数中分裂的第二个峰的第一个成分以及第二个峰之后的其他峰逐渐消失；第一个峰变窄，急剧下降到第一个最小值。随着粒径减小，角分布中120度处的峰以及随后60度处的峰将逐渐消失；配位数分布向左移动并变窄。对于1微米的颗粒，平均配位数可降至低至2的值，形成非常松散的链状结构。分析了作用于稳定堆积中单个颗粒的颗粒间力，并表明其与堆积性质有关。
