1. Advancing Contact Line Dynamics Induced by Soluble Surfactant Deposition on a Thin Liquid Film.
- Author
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Beacham, D. R., Matar, O. K., and Craster, R. V.
- Subjects
LIQUID films ,MICELLES ,DYNAMICS ,NANOPARTICLES ,SURFACE active agents - Abstract
Recent experimental results have helped to elucidate the mechanisms of surfactant enhanced spreading and the subclass of superspreading. Unfortunately, the multiple scale nature of the problem has hindered a general theoretical treatment. Macroscopic models have not had the required resolution to capture the dynamics at the contact line where a thin precursor layer is seen in experiments and dynamic variations in wettability are expected to be important. We examine the dynamics in this region in the presence of surfactant above the critical micelle concentration. We couple a lubrication model to advection-diffusion equations for surfactant transport allowing for micelle formation and break-up in the bulk and adsorptive fluxes at both interfaces. Equations of state are supplied to model variations in surface tension and wettability. We exploit the structural disjoining pressure within our lubrication model, noting the importance of microscopic forces at this scale. Promisingly, the use of the disjoining pressure has recently yielded the formation of step like structures in nanoparticle laden fluids [1]. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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