title: Revisiting the Saffman-Taylor experiment: imbibition patterns and liquid-entrainment transitions.
abstract: We revisit the Saffman-Taylor experiment focusing on the forced-imbibition regime where the displacing fluid wets the confining walls. We demonstrate a new class of invasion patterns that do not display the canonical fingering shapes. We evidence that these unanticipated patterns stem from the entrainment of thin liquid films from the moving meniscus. We then theoretically explain how the interplay between the fluid flow at the contact line and the interface deformations results in the destabilization of liquid interfaces. In addition, this minimal model conveys a unified framework which consistently accounts for all the liquid-entrainment scenarios that have been hitherto reported.
authors.affiliation: PMMH-CNRS-ESPCI ParisTech-Université Paris 6-Université Paris 7, 10, rue Vauquelin, 75005 Paris, France and Total France, Pole d'Etudes et de Recherche de Lacq, BP47-64170 Lacq, France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Levaché
authors.affiliation: PMMH-CNRS-ESPCI ParisTech-Université Paris 6-Université Paris 7, 10, rue Vauquelin, 75005 Paris, France and Ecole Normale Supérieure de Lyon, CNRS, Université de Lyon, 46, allée d'Italie, 69007 Lyon, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Bartolo