Matthieu Roche - Continuous Marangoni flows
|Starts:||14:00 5 Feb 2020|
|Ends:||15:00 5 Feb 2020|
|What is it:||Seminar|
|Organiser:||Department of Mathematics|
|Who is it for:||University staff, External researchers, Current University students|
Matthieu Roche (University of Paris Diderot) joins us for this seminar in the Physical Applied Mathematics Series.
Title: Continuous Marangoni flows
Abstract: The presence of a surface-concentration gradient of surface-active molecules along an interface between two liquids leads to the existence of an interfacial tension gradient and to the establishment of a flow in the volume of each liquid: this is the Marangoni effect. Although important for many applications (coating, stability of soap films, etc.), the Marangoni solutal effect has been studied mainly in the case of thin liquid films, and the theoretical interpretation considers mostly insoluble molecules. However, the solubility of the surfactants must affect the Marangoni flow obtained since the molecules can not only move along the interface, but also desorb from it to diffuse into the volume. During this seminar, I will present work that colleagues and I have carried until now on the effect of solubility on Marangoni flows. I will show how we have related the properties of Marangoni flow to the properties of the surfactants (solubility, presence of impurities, system geometry, etc.). This link between physico-chemistry and hydrodynamics makes it possible to quickly characterise the solution thermodynamics of surfactants. I will then present a study on the structure of the flow, and I will show in particular how these flows lead to interesting observations about vortex sheets and their roll-up, and how we can rationalize them.
Organisation: University of Paris Diderot
Travel and Contact Information
Frank Adams 1
Alan Turing Building