Dresden 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

SYSS: Structure Formation and Self-Organization in non-equilibrium Systems

SYSS 1: Structure Formation and Self-Organization in non-equilibrium Systems I

SYSS 1.6: Vortrag

Donnerstag, 30. März 2006, 11:00–11:15, BAR Sch\"o

Gas-Enrichment at Liquid-Wall Interfaces — •Stephan M. Dammer and Detlef Lohse — University of Twente, Physics of Fluids

Molecular dynamics simulations are performed to study the effects of dissolved gas on liquid-wall interfaces. The systems are composed of different particle species (liquid/gas/wall) that interact via Lennard-Jones potentials. Liquid-gas mixtures in contact with walls exhibit gas enrichment at the walls, which increases with increasing hydrophobicity, quantified by the contact angle which is obtained from additional simulations of droplets at walls. When compared to the gas concentration in the bulk of the liquid, for atomically smooth hydrophobic walls the observed gas enrichment can exceed more than two orders of magnitude. In the case of nanometric wall roughness gas accumulates in nano-crevices on hydrophobic walls. Close to the walls the liquid shows a layered structure which is less pronounced for increasing contact angle and which for large contact angle is considerably altered by the presence of a gas. Furthermore, we investigate the influence of the gas enrichment at hydrophobic walls on dynamical properties, such as the slip length, by nonequilibrium molecular dynamics simulations.