Analysis of Cohesive Microsized Particle Packing Structure Using History-Dependent Contact Models
Analysis of Cohesive Microsized Particle Packing Structure Using History-Dependent Contact Models
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DOI：
10.1115/1.4031246
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发表时间：
2016-03
影响因子：
4
通讯作者：
Raihan Tayeb;Xin Dou;Yijin Mao;Yuwen Zhang
中科院分区：
文献类型：
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作者：
Raihan Tayeb;Xin Dou;Yijin Mao;Yuwen Zhang
采用离散元法（DEM），采用两种不同的历史相关接触模型，研究了不同粒径和粒径分布（包括单粒径分布、均匀分布和高斯分布）的粘性微粒的颗粒堆积结构。模拟是在广泛使用的开放源代码LAMMPS粒度包的分支基础上扩展的DEM模拟包ligghts框架下进行的。考虑了由平移和旋转引起的接触力、与其他颗粒或容器边界碰撞引起的摩擦力和阻尼力、凝聚力、货车德瓦尔斯力和重力。径向分布函数（RDFs），力分布，孔隙率，和协调数下的凝聚力和非凝聚力的条件下报告。结果表明，颗粒尺寸和尺寸分布对颗粒堆积的堆积密度有很大影响：高斯分布的颗粒堆积密度最低，均匀分布的颗粒次之，单一尺寸分布的颗粒堆积密度最高。研究还发现，内聚效应对体系配位数的影响并不显著，而配位数主要取决于粒径和粒径分布。虽然净力分布的大小不同，但两种接触模型之间的孔隙率、配位数和净力大小的平均值的结果没有显著差异。
Granular packing structures of cohesive microsized particles with different sizes and size distributions, including monosized, uniform, and Gaussian distribution, are investigated by using two different history dependent contact models with discrete element method (DEM). The simulation is carried out in the framework of liggghts, which is a DEM simulation package extended based on branch of granular package of widely used open-source code LAMMPS. Contact force caused by translation and rotation, frictional and damping forces due to collision with other particles or container boundaries, cohesive force, van der Waals force, and gravity is considered. The radial distribution functions (RDFs), force distributions, porosities, and coordination numbers under cohesive and noncohesive conditions are reported. The results indicate that particle size and size distributions have great influences on the packing density for particle packing under cohesive effect: particles with Gaussian distribution have the lowest packing density, followed by the particles with uniform distribution; the particles with monosized distribution have the highest packing density. It is also found that cohesive effect to the system does not significantly affect the coordination number that mainly depends on the particle size and size distribution. Although the magnitude of net force distribution is different, the results for porosity, coordination number, and mean value of magnitude of net force do not vary significantly between the two contact models.