Eur. Phys. J. Special Topics 197, 213-220 (2011)
https://doi.org/10.1140/epjst/e2011-01462-7

Regular Article

Note on thin film equations for solutions and suspensions

Department of Mathematical Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK

^a e-mail: u.thiele@lboro.ac.uk; homepage: www.uwethiele.de

Received: 2 June 2011
Revised: 15 June 2011
Published online: 30 August 2011

Abstract

This note discusses how one may further develop thin film evolution equations for solutions and suspensions. First, we review the time evolution equation of a film or drop of simple liquid under the sole influence of wettability and capillarity and its formulation as a gradient dynamics. Second, we introduce such a gradient dynamics for a film of suspension or solution and show that it is equivalent to thin film equations in the literature. Finally, the new formulation is used to discuss extensions towards solute molecules/particles with net attractive interactions, decomposing solute-solvent systems and a solute-dependent wettability.