title: Vesicle dynamics in a confined Poiseuille flow: from steady state to chaos.
abstract: Red blood cells (RBCs) are the major component of blood, and the flow of blood is dictated by that of RBCs. We employ vesicles, which consist of closed bilayer membranes enclosing a fluid, as a model system to study the behavior of RBCs under a confined Poiseuille flow. We extensively explore two main parameters: (i) the degree of confinement of vesicles within the channel and (ii) the flow strength. Rich and complex dynamics for vesicles are revealed, ranging from steady-state shapes (in the form of parachute and slipper shapes) to chaotic dynamics of shape. Chaos occurs through a cascade of multiple periodic oscillations of the vesicle shape. We summarize our results in a phase diagram in the parameter plane (degree of confinement and flow strength). This finding highlights the level of complexity of a flowing vesicle in the small Reynolds number where the flow is laminar in the absence of vesicles and can be rendered turbulent due to elasticity of vesicles.
authors.affiliation: Department of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany and Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France and LMPHE, URAC 12, Faculté des Sciences, Université Mohammed V-Agdal, Rabat, Morocco.
authors.forename: Othmane
authors.initials: O
authors.lastname: Aouane
authors.affiliation: Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France.
authors.forename: Marine
authors.initials: M
authors.lastname: Thiébaud
authors.affiliation: LMPHE, URAC 12, Faculté des Sciences, Université Mohammed V-Agdal, Rabat, Morocco.
authors.forename: Abdelilah
authors.initials: A
authors.lastname: Benyoussef
authors.affiliation: Department of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Wagner
authors.affiliation: Université Grenoble Alpes, LIPHY, F-38000 Grenoble, France.
authors.forename: Chaouqi
authors.initials: C
authors.lastname: Misbah
mesh_terms: D048430:Cell Shape; D004548:Elasticity; D004912:Erythrocytes / Q000166:cytology; D008051:Lipid Bilayers; D008955:Models, Cardiovascular; D009038:Motion; D017711:Nonlinear Dynamics
chemical_list: D008051:Lipid Bilayers