Shape evolution and scaling analysis of soluble cylinders in dissolutive flow

Abstract

The evolution of solid shapes in dissolutive flows is studied using molecular dynamics simulations. The final self-similar structures of the solid are distinct under the convection- and diffusion-dominated conditions. Introducing a dimensionless number, Ds, allows characterizing the relative influence of convection and diffusion on the final structure. When convection dominates, the convergent shape of the solid is approximately triangular, while the solid is more likely to be sculptured into a cylinder when diffusion dominates. There is a critical value of Ds that controls the transition between convection- and diffusion-dominated cases. However, the convergent shapes are insensitive to their initial states due to the solid assembly at the nanoscale. Furthermore, we discuss the influences of solid dissolution and assembly on the liquid density along different directions and provide fitting curves for the theoretical density distribution as explained from the Smoluchowski equation. Finally, the scaling laws are constructed to quantify the solid evolution, which can analytically forecast the shape evolution under different dominant factors. We believe that these findings provide theoretical support for structure optimization and industrial applications.

Shape optimization of a meniscus-adherent nanotip

“…The dissolubility of the solid is controlled by ε : a smaller ε generates a higher dissolubility. 40 All the simulations are under periodic conditions. Compared with the fully 3-dimensional system, the 2-dimensional system can produce the expected results with a much smaller number of atoms.…”

Water transport performance of inhomgenous nanoconfined systems

“…非周期边界条件, 水模型采用SPC/E [13] , 水分子键和角 采用SHAKE [13] 算法固定, 原子间的相互作用势采用 Lennard-Jones (LJ)势以及库仑相互作用, 势能计算如 下 [5,14,17] :…”

“…Zhao等人 [11] 研究了0.6-1.5 nm高度平行石墨烯通道内 水的输运行为, 发现石墨烯狭缝孔道的尺寸效应及表 面性质对受限水分子的结构性质及动力学行为有着直 接的影响 [11][12][13][14][15][16][17][18][19] . 此外, Algara-Siller等人 [20] 用实验证明 了在两片石墨烯包裹下, 水可以结成四方冰的形态.…”