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arXiv · 0809.4028

Vesicles in a Poiseuille flow

Gerrit Danker·Petia Vlahovska·Chaouqi Misbah
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Abstract

Vesicle dynamics in unbounded Poiseuille flow is analyzed using a small-deformation theory. Our analytical results quantitatively describe vesicle migration and provide new physical insights. At low ratio between the inner and outer viscosity $λ$ (i.e. in the tank-treading regime), the vesicle always migrates towards the flow centerline, unlike other soft particles such as drops. Above a critical $λ$, vesicle tumbles and cross-stream migration vanishes. A novel feature is predicted, namely the coexistence of two types of nonequilibrium configurations at the centreline, a bullet-like and a parachute-like shapes.

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BibTeXRIS

Gerrit Danker, Petia Vlahovska, Chaouqi Misbah. 2008-09-23. Vesicles in a Poiseuille flow. https://doi.org/10.1103/physrevlett.102.148102

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