Pihlajamaa Ilian, de Bruijn René, van der Schoot Paul
Group of Soft Matter and Biological Physics, Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands.
Soft Matter. 2022 Jun 1;18(21):4167-4177. doi: 10.1039/d2sm00375a.
We combine a heuristic theory of geometric percolation and the Smoluchowski theory of colloid dynamics to predict the impact of shear flow on the percolation threshold of hard spherical colloidal particles, and verify our findings by means of molecular dynamics simulations. It appears that the impact of shear flow is subtle and highly non-trivial, even in the absence of hydrodynamic interactions between the particles. The presence of shear flow can both increase and decrease the percolation threshold, depending on the criterion used for determining whether or not two particles are connected and on the Péclet number. Our approach opens up a route to quantitatively predict the percolation threshold in nanocomposite materials that, as a rule, are produced under non-equilibrium conditions, making comparison with equilibrium percolation theory tenuous. Our theory can be adapted straightforwardly for application in other types of flow field, and particles of different shape or interacting other than hard-core potentials.
我们将几何渗流的启发式理论与胶体动力学的斯莫卢霍夫斯基理论相结合，以预测剪切流对硬球形胶体颗粒渗流阈值的影响，并通过分子动力学模拟验证我们的发现。结果表明，即使在颗粒之间不存在流体动力学相互作用的情况下，剪切流的影响也是微妙且非常复杂的。根据用于确定两个颗粒是否相连的标准以及佩克莱数，剪切流的存在既可以提高也可以降低渗流阈值。我们的方法开辟了一条定量预测纳米复合材料渗流阈值的途径，通常情况下，纳米复合材料是在非平衡条件下生产的，这使得与平衡渗流理论的比较变得不那么可靠。我们的理论可以直接适用于其他类型的流场，以及不同形状或除硬核势之外存在相互作用的颗粒。
