无定形态及晶态颗粒堆积结构的三维构建及表征

Construction and Structure Characterization of Amorphous and Crystalline Packings of Spheres by Discrete Element Method

采用离散元法对等径球在振动条件下堆积形成的无定形结构及晶态结构进行三维构建,并对两种堆积结构的宏观性能如堆积密度及微观性能如配位数、径向分布函数及Voronoi-Delaunay孔尺寸分布进行表征及对比。结果表明:所获得的无定形结构和晶态结构的最大相对堆积密度分别为0.64和0.74,对应的配位数分布的峰值分别为7和12,径向分布函数曲线上,晶态堆积中粒子之间的位置具有长程相关性,同时晶态结构所对应的尺寸分布较无定形结构高且窄,且整体左移。

The amorphous and crystalline packings of equal spheres under vibrations were numerically constructed by discrete element method, and the macro property such as packing density and the micro properties such as coordination number, radial distribution function, and Voronoi-Delaunay void size distribution for both structures were characterized and compared. The results showed that the maximum relative packing densities for both amorphous and crystalline structures were 0.64 and 0.74, respectively, the corresponding peaks for coordination number distribution were 7 and 12, the long distance correlation in radial distribution function distribution could be found for crystalline structure. Compared with the amorphous structure, the void size distribution for the crystalline structure was higher and narrower, and shifted to the left.