Effect of the interaction strength and range on the wetting behavior in confined binary fluid

The effects of interaction strength and range on the wetting behavior in two-dimensional binary fluid (which is composed of water-like and water-oil particles) confined between two parallel plane walls have been investigated by using the free energy analysis and discontinuous molecular dynamic simulations. Some rules are found. When the concentration of water-like particles c(w) is comparable to that of oil-like particles c(o), the concave-water-lens may exist. As the strength or range of the preferential attraction between the walls and water-like particles increase, the system undergoes the transition from the partial wetting to complete wetting, and the occupied rate of water-like particles on the wall eta varies gradually from a low fractional value to unity. When cw is very smaller or larger than co, the concave-water-lens exist no long, and eta increases abruptly from a low fractional value to unity. (C) 2004 Elsevier B.V. All rights reserved.