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Journal of Bionic Engineering

, Volume 5, Issue 4, pp 271–281 | Cite as

Molecular Dynamics Simulation of Behaviours of Non-Polar Droplets Merging and Interactions with Hydrophobic Surfaces

  • Y. Y. Yan
  • C. Y. JiEmail author
Article

Abstract

This paper presents a molecular dynamics simulation of the behaviours of non-polar droplets merging and also the fluid molecules interacting with a hydrophobic surface. Such behaviours and transport phenomena are popular in general microchannel flow boiling and two-phase flow. The droplets are assumed to be composed of Lennards-Jones type molecules. Periodic boundary conditions are applied in three coordinate directions of a 3-D system, where there exist two liquid droplets and their vapour. The two droplets merge when they come within the prescribed small distance. The merging of two droplets apart from each other at different initial distances is tested and the possible larger (or critical) non-dimensional distance, in which droplets merging can occur, is discussed. The evolution of the merging process is simulated numerically by employing the Molecular Dynamics (MD) method. For interactions with hydrophobic solid wall, a system with fluid confined between two walls is used to study the wetting phenomena of fluid and solid wall. The results are compared with those of hydrophilic wall to show the unique characteristics of hydrophobic interactions by microscopic methods.

Keywords

molecular dynamics simulation mist flow droplets merging hydrophobic wetting 

Nomenclature

Nomenclature

F

intermolecular force

m

mass

N

molecular number in the system

r

intermolecular distance

T

temperature

V

system volume

ε

energy parameter of L-J potential

σ

length parameter of L-J potential or surface tension

ϕ

potential energy

Subscripts

L

liquid

S

solid

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Copyright information

© Jilin University 2008

Authors and Affiliations

  1. 1.School of the Built EnvironmentUniversity of NottinghamNottinghamUK

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