. Dans-ce-chapitre, existence d'une nouvelle transition capillaire provenant de la déstabilisation du ménisque entre l'eau et l'huile en films minces d'eau se propageant le long des parois. L'´ ecoulement

. Dans-le-chapitre-suivant, on s'intéressera ainsì a ces deux transitions d'entra??entra??nement et, plusparticulì erement, ` a comprendre ce qui détermine l'apparition de l

A. De and . Marchand, Pour ces troisétudestroisétudes, le rapport de mobilité utilisé est au plus de l'ordre de 1 et est généralement bien inférieur. Pour rappel, notré etude du chapitre 3 s'est focalisée uniquement sur le régime des hauts rapports de viscosité dans le but d'´ etudier l'influence du mouillage sur l'instabilité de Saffman-Taylor. Ainsi, pour essayer d'obtenir le second type d'invasion, on regarde ce que donne notre modèle théorique lorsque l'on baisse le rapport de viscositéviscositéà angle de contact toujours faible, Cette situation correspond dans le tableau 4.2 aux travaux

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