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arXiv · cond-mat/0702650

Dynamics of nearly spherical vesicles in an external flow

V. V. Lebedev·K. S. Turitsyn·S. S. Vergeles
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Abstract

We analytically derive an equation describing vesicle evolution in a fluid where some stationary flow is excited regarding that the vesicle shape is close to a sphere. A character of the evolution is governed by two dimensionless parameters, $S$ and $Λ$, depending on the vesicle excess area, viscosity contrast, membrane viscosity, strength of the flow, bending module, and ratio of the elongation and rotation components of the flow. We establish the ``phase diagram'' of the system on the $S-Λ$ plane: we find curves corresponding to the tank-treading to tumbling transition (described by the saddle-node bifurcation) and to the tank-treading to trembling transition (described by the Hopf bifurcation).

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V. V. Lebedev, K. S. Turitsyn, S. S. Vergeles. 2007-02-27. Dynamics of nearly spherical vesicles in an external flow. https://doi.org/10.1103/physrevlett.99.218101

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