Note on thin film equations for solutions and suspensions

Thiele U

Research article (journal) | Peer reviewed

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 equa- tions in the literature. Finally, the new formulation is used to discuss extensions towards solute molecules/particles with net attractive in- teractions, decomposing solute-solvent systems and a solute-dependent wettability.