Migration of rigid particles in non-Brownian viscous suspensions
Migration of rigid particles in non-Brownian viscous suspensions
复制标题
非布朗粘性悬浮液中刚性颗粒的迁移
DOI：
10.1063/1.3079672
复制
发表时间：
2009
影响因子：
4.6
通讯作者：
D. Lhuillier
中科院分区：
文献类型：
--
作者：
D. Lhuillier
显然需要获得一组描述多相流及其构型复杂性的封闭方程。尽管刚性粒子的界面被冻结，但刚性粒子的悬浮也受到了这个问题的关注。两相之间的相对运动的描述仍然是有争议的，特别是关于作用在颗粒上的力，涉及到它们的浓度梯度或剪切速率梯度。我们的目的是(A)建立一个专门为分散在粘性液体中的颗粒而设计的双流体模型，(B)借助低雷诺数流体力学来封闭刚性颗粒的模型。除了重力的明显作用外，颗粒相对于流体的迁移是由两种不同的物理现象引起的：(A)直接颗粒间力引起的应力不均匀和(B)作用于颗粒的流体动力中的类Fick项。
There is an obvious need for obtaining a closed set of equations describing multiphase flows and the complexity of their configurations. Despite their “frozen” interfaces, suspensions of rigid particles are also concerned by this issue. The description of the relative motion between the two phases is still controversial, in particular, concerning the forces acting on the particles and involving their concentration gradient or a shear rate gradient. It is our purpose here (a) to develop a two-fluid model especially designed for particles dispersed in a viscous liquid and (b) to close the model for rigid particles with the help of low-Reynolds-number hydrodynamics. Besides the obvious role of gravity forces, the migration of particles relative to the fluid is shown to result from two different physical phenomena: (a) the inhomogeneity of the stress resulting from direct interparticle forces and (b) Fick-like terms in the hydrodynamic force acting on the particles.