MARTINI Coarse-Grained Model of Solid-Liquid Interface

Capillary driven motion of fluids is responsible for many natural phenomena and effective on several industrial applications. By way of illustration, consider water remediation and oil recovery, as well as the operation of some laboratory equipment such as trolling mode atomic force microscopy. Experimental study of formation of meniscus layer as a capillary driven motion in scales smaller than micro is extremely difficult and exceedingly costly. Consequently, computational models seem to be appropriate to study the capillary driven motion in nanoscale. In the present work, we have utilized the MARTINI coarse graining method to investigate the establishment of meniscus layer around a cylindrical nanoneedle. We have demonstrated that growth of meniscus layer height is a function of square root of time, which shows agreement with Lucas -Washburn relation for capillary penetration pace. Accordingly, consistency of the utilized model with the physics of the phenomenon can be concluded. Also the effect of variation of nonbonded solid fluid interaction potential parameters as well as needle diameter is investigated on the meniscus geometry, capillary force, and radial distribution function. Moreover, it is observed that a nondimensional comparison with the nearest available experimental data demonstrates a reasonable agreement.