Characteristics of Momentum Transport in a Nanoscale Liquid Bridge - Archive ouverte HAL Accéder directement au contenu
Communication Dans Un Congrès Année : 2012

Characteristics of Momentum Transport in a Nanoscale Liquid Bridge

Résumé

In lubricated contacts, when the lubricant supply is not sufficient to fill the gap between the solid surfaces, or when the wettability conditions are bad, the film can fractionate into disjointed liquid bridges. In such conditions, the liquid surface tension at the menisci and the wall boundary conditions strongly influence the tribological behavior of the fractionated film. Liquid flows under the shape of nano/microscale liquid bridges, often occur in nano/micro devices, or can be formed due to capillary condensation between rough surfaces. The aim of this work is to investigate the dynamic nanoscale behavior of liquid bridges by Molecular Dynamics methods and to focus on the nanoscale phenomena occurring in the interfacial regions. In this research, the lubrication phenomenon by shearing a nanoscale liquid bridge without surfaces was simulated using the molecular dynamics method by changing the width of the liquid bridge and the momentum transport phenomena of liquid bridge were analyzed. The Fennell method was used to calculate the Coulombic interaction rather than Ewald method and the Lees-Edwards method was used to maintain the velocity gradient in the liquid bridge. The bulk and interfacial region of the liquid bridge were determined first to estimate the overall viscosity coefficient of the liquid bridge. The overall viscosity coefficient of the liquid bridges was then modeled by considering two contributions from the bulk and interfacial regions and the momentum fluxes or viscosity coefficient in the bulk and interfacial region was obtained. The model approximately expresses the simulation results and the viscosity of the interfacial region was determined to be from one fourth to one third of that for the bulk region. In addition, the partial momentum flux was calculated to verify the validity of the proposed model. These results are consistent with each other and it can be said that the momentum fluxes in bulk and interfacial region obtained in this research is valid.

Domaines

Autre
Fichier non déposé

Dates et versions

hal-00862957 , version 1 (17-09-2013)

Identifiants

  • HAL Id : hal-00862957 , version 1

Citer

Takashi Tokumasu, Marie-Hélène Meurisse, Nicolas Fillot, Philippe Vergne. Characteristics of Momentum Transport in a Nanoscale Liquid Bridge. NordTrib 2012 Symposium on Tribology, Jun 2012, Trondheim, Norway. ⟨hal-00862957⟩
45 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More