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A Thermodynamic Model of Electric-Field-Induced Pattern Formation in Binary Dielectric Fluids

M. D. Johnson·X. Duan·Brett Riley·Aniket Bhattacharya·Weili Luo
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Abstract

An electric-field-induced phase transition and pattern formation in a binary dielectric fluid layer are studied using a coarse-grained free energy functional. The electrostatic part of the free energy is a nonlinear functional of the dielectric function, which depends in turn on the local colloidal concentration. We determine the phase co-existence curve and find that beyond a critical electric field the system phase separates. Accompanying the phase separation are patterns similar to those observed in a spinodal decomposition of an ordinary binary fluid. The temporal evolution of the phase separating patterns are discussed both analytically and numerically by integrating a Cahn-Hilliard type of equation.

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M. D. Johnson, X. Duan, Brett Riley, Aniket Bhattacharya, Weili Luo. 2002-11-21. A Thermodynamic Model of Electric-Field-Induced Pattern Formation in Binary Dielectric Fluids. https://arxiv.org/abs/cond-mat/0211495

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