论文标题
在流体流体界面上带电的和未充电的棕色胶体之间的流体动力相互作用
Hydrodynamic Interactions Between Charged and Uncharged Brownian Colloids at a Fluid-Fluid Interface
论文作者
论文摘要
假设：漂浮在流体/流体界面上的胶体的集体动力学和自组装是确定性的横向相互作用力，沿表面胶体运动的粘性和热（布朗）波动之间的平衡。随着胶体尺寸的减小，热力变得重要，并可能影响自组装成有序的模式和晶体结构，这是各种材料应用的起点。数字：涉及两个粒子的Langevin动态模拟，横跨具有高粘度对比度的液体/液体界面，以描述布朗和非布朗尼统治方案中颗粒的外侧界面组件。这些模拟包含毛细血管吸引力，静电排斥，热波动以及颗粒之间的HI（包括颗粒浸入深度的影响）。对中性湿颗粒的仿真结果表示，在界面处形成90度的接触角。发现：在PE数的较大值下观察到聚类，分形生长和颗粒排序，而较小的PE数表现出较高的屈服状态概率，在该状态下，颗粒在空间中保持不相关并且更广泛地分离。
Hypothesis: The collective dynamics and self-assembly of colloids floating at a fluid/fluid interface is a balance between deterministic lateral interaction forces, viscous resistance to colloid motion along the surface and thermal (Brownian) fluctuations. As the colloid size decreases, thermal forces become important and can affect the self assembly into ordered patterns and crystal structures that are the starting point for various materials applications. Numerics: Langevin dynamic simulations involving two particles straddling a liquid/liquid interface with a high viscosity contrast are presented to describe the lateral interfacial assembly of particles in Brownian and non-Brownian dominated regimes. These simulations incorporate capillary attraction, electrostatic repulsion, thermal fluctuations and HI between particles (including the effect of the particle immersion depth). Simulation results are presented for neutrally wetted particles which form a contact angle of 90 degrees at the interface. Findings: Clustering, fractal growth and particle ordering are observed at critically large values of the Pe numbers, while smaller Pe numbers exhibit higher probabilities of yielding states in which particles remain uncorrelated in space and more widely separated.
