title: Vesicles in Poiseuille flow.
abstract: Blood microcirculation critically depends on the migration of red cells towards the flow centerline. We identify theoretically the ratio of the inner over the outer fluid viscosities lambda as a key parameter. At low lambda, the vesicle deforms into a tank-treading ellipsoid shape far away from the flow centerline. The migration is always towards the flow centerline, unlike drops. Above a critical lambda, the vesicle tumbles or breaths and migration is suppressed. A surprising coexistence of two types of shapes at the centerline, a bulletlike and a parachutelike shape, is predicted.
authors.affiliation: Laboratoire de Spectrométrie Physique, UMR, 140 avenue de la physique, Université Joseph Fourier Grenoble, and CNRS, 38402 Saint Martin d'Heres, France.
authors.forename: Gerrit
authors.initials: G
authors.lastname: Danker
authors.forename: Petia M
authors.initials: PM
authors.lastname: Vlahovska
authors.forename: Chaouqi
authors.initials: C
authors.lastname: Misbah
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology*; D003198:Computer Simulation; D004912:Erythrocytes / Q000166:cytology / Q000502:physiology*; D006801:Humans; D008833:Microcirculation / Q000502:physiology*; D055806:Microvessels / Q000166:cytology / Q000502:physiology*; D008955:Models, Cardiovascular