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Phase separation in a chaotic flow

Ludovic Berthier·Jean-Louis Barrat·Jorge Kurchan
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Abstract

The phase separation between two immiscible liquids advected by a bidimensional velocity field is investigated numerically by solving the corresponding Cahn-Hilliard equation. We study how the spinodal decomposition process depends on the presence -or absence- of Lagrangian chaos. A fully chaotic flow, in particular, limits the growth of domains and for unequal volume fractions of the liquids, a characteristic exponential distribution of droplet sizes is obtained. The limiting domain size results from a balance between chaotic mixing and spinodal decomposition, measured in terms of Lyapunov exponent and diffusivity constant, respectively.

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BibTeXRIS

Ludovic Berthier, Jean-Louis Barrat, Jorge Kurchan. 2001-02-08. Phase separation in a chaotic flow. https://doi.org/10.1103/physrevlett.86.2014

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