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arXiv · 2011.00724

Note on the pairwise interactions of surfactant-covered drops in a uniform electric field

Chiara Sorgentone·Petia Vlahovska
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Abstract

We study the effect of surfactant on the pairwise interactions of drops in an applied uniform DC electric field using a combination of numerical simulations based on a boundary integral formulation and an analytical theory assuming small drop deformations. The surfactant is assumed to be insoluble in the bulk-phase fluids. We show that the surfactant weakens the electrohydrodynamic flow and thus dielectrophoretic interactions play more prominent role in the dynamics of surfactant-covered drops compared to clean drops. If drop conductivity is the same as the suspending fluid, a nondiffusing surfactant can arrest the drops' relative motion thereby effectively preventing coalescence.

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Chiara Sorgentone, Petia Vlahovska. 2020-10-29. Note on the pairwise interactions of surfactant-covered drops in a uniform electric field. https://arxiv.org/abs/2011.00724

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