Determination of Interfacial Concentration of a Contaminated Droplet from Shape Oscillation Damping

Benjamin Lalanne (1, 2) , Olivier Masbernat (1, 2) , Frédéric Risso (3, 2)

1 LGC - Laboratoire de Génie Chimique
2 FERMAT - Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts
3 IMFT - Institut de mécanique des fluides de Toulouse

We present a method to measure very small interfacial concentration of a contaminant that is irreversibly adsorbed on the interface of a bubble or droplet. It is an application of the linear theory of shape oscillation which relates the Gibbs elasticity to the damping, extended by numerical simulations to deal with moving droplets. It explains previous unexpected observations on the effect of contamination at various oscillation wavelengths. The experimental procedure is easy to implement and can thereby deeply enhance the analysis of most systems involving uncontrolled contamination.

Mots clés: Drop and bubble dynamics; Shape oscillation; Surfactants -Marangoni stresses; Frequency; Damping

Domaines: Génie chimique; Génie des procédés

Benjamin Lalanne, Olivier Masbernat, Frédéric Risso. Determination of Interfacial Concentration of a Contaminated Droplet from Shape Oscillation Damping. Physical Review Letters, 2020, 124 (19), pp.0. ⟨10.1103/PhysRevLett.124.194501⟩. ⟨hal-02641224⟩