Transient surface tension in miscible liquids

Laurent Lacaze (1) , Patrick Guenoun (2) , Daniel Null Beysens (3) , Michel Delsanti , Philippe Petitjeans (3) , Pascal Kurowski (3)

1 IMFT - Institut de mécanique des fluides de Toulouse
2 SPEC - UMR3680 - Service de physique de l'état condensé
3 PMMH - Physique et mécanique des milieux hétérogenes (UMR 7636)

Evidence of the existence of a transient surface tension between two miscible fluid phases is given. This is done by making use of a density matched free of gravity perturbations, binary liquid of isobutyric acid and water, which presents a miscibility gap and is studied by light scattering. The experiment is performed very near the critical point of the binary liquid, where the diffusion of phases is extremely slow. The surface tension is deduced from the evolution of the structure factor obtained from low angle light scattering. The latter evolution is successfully analyzed in terms of a local equilibrium diffusive approach that makes explicit how the surface tension decreases with time.

Domaines: Milieux fluides et réactifs

Laurent Lacaze, Patrick Guenoun, Daniel Null Beysens, Michel Delsanti, Philippe Petitjeans, et al.. Transient surface tension in miscible liquids. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2010, 82 (4), ⟨10.1103/PhysRevE.82.041606⟩. ⟨hal-02454194⟩