Random loose packing of cohesive granular materials
Random loose packing of cohesive granular materials
复制标题
DOI：
10.1209/epl/i2006-10208-4
复制
发表时间：
2006-09-01
期刊：
影响因子：
--
通讯作者：
Castellanos, A.
中科院分区：
文献类型：
--
作者：
Valverde, J. M.;Castellanos, A.
非粘性硬球的无序堆积的体积分数phi可以在零重力应力极限下的无规松散堆积（phi（RLP）类似于或等于0.56）和无规紧密堆积（phi（RCP）类似于或等于0.64）之间变化。然而，当存在颗粒间吸引力时，已知对于纳米颗粒，f可以低至类似于0.01。实验和数值计算结果表明，f随颗粒间吸引力与颗粒重量之比（Bog）的增大而减小。我们专注于在零重力（堵塞过渡）的限制解决的粘性颗粒的包装分数。从悬浮液中颗粒团聚模型出发，得到了一个简单的方程：φ（J）= φ（J）* Bo（g）（（D-3）/（D+2）），其中φ（*）（J）为堵塞时颗粒团聚体的体积分数，与φ（RLP）相近，D为分形维数。我们的实验结果符合这个方程，并表明在悬浮液中的颗粒团聚是相关的物理机制来理解的粘性颗粒的包装。
The volume fraction phi of a disordered packing of noncohesive hard spheres may vary between the random loose packing at the limit of zero gravitational stress (phi(RLP) similar or equal to 0.56) and the random close packing (phi(RCP) similar or equal to 0.64). When interparticle attractive forces are present it is known however that f can be as low as similar to 0.01 for nanoparticles. Experimental and numerical works show that f decreases as the ratio of interparticle attractive force to particle weight ( Bog) is increased. We focus on the packing fraction of cohesive particles settled at the limit of zero gravity ( jamming transition). From a model of particle agglomeration in suspensions wefind the simple equation phi(J) similar or equal to phi(J)* Bo(g)((D-3)/(D+2)) ,where phi(*)(J) is the volume fraction of particle agglomerates at jamming, which is close to phi(RLP), and D their fractal dimension. Our experimental results on. ne powders agree with this equation and show that agglomeration of particles in suspension is the relevant physical mechanism to understand the packing of cohesive particles.