title: Tumbling of vesicles under shear flow within an advected-field approach.
abstract: We study dynamics of vesicles with a viscosity contrast between the interior and exterior, and subjected to a linear shear flow. It is shown that the vesicle, which assumes a steady orientation with respect to the shear flow for r identical with eta(in)/eta(out)<r(c) (where eta(in) and eta(out) are the internal and external viscosities, and r(c) is a critical value which depends upon the swelling factor), undergoes a tumbling bifurcation for r>or=r(c). Tumbling occurs as a saddle-node bifurcation. We present analytical and numerical results. We develop a powerful method, the advected-field approach. This method allows one to treat several different phenomena with great flexibility.
authors.affiliation: Groupe de Recherche sur les Phénomènes hors Equilibre, LSP, Université Joseph Fourier, CNRS UMR5588, Boîte Postale 87, F-38402 Saint-Martin d'Hères CEDEX, France.
authors.forename: T
authors.initials: T
authors.lastname: Biben
authors.forename: C
authors.initials: C
authors.lastname: Misbah
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D004912:Erythrocytes / Q000473:pathology / Q000502:physiology*; D006801:Humans; D008962:Models, Theoretical; D013314:Stress, Mechanical; D014783:Viscosity