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arXiv · 2408.03392

Ultra-soft liquid-ferrofluid interfaces

Arvind Arun Dev·Thomas Hermans·Bernard Doudin
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Abstract

Soft interfaces are ubiquitous in nature, governing quintessential hydrodynamics functions, like lubrication, stability and cargo transport. It is shown here how a magnetic force field at a magnetic-nonmagnetic fluid interface results in an ultra-soft interface with nonlinear elasticity and tunable viscous shear properties. The balance between magnetic pressure, viscous stress and Laplace pressure results in a deformed and stable liquid-in-liquid tube with apparent elasticity in the range 2 kPa -10 kPa, possibly extended by a proper choice of liquid properties. Such highly deformable liquid-liquid interfaces of arbitrary shape with vanishing viscous shear open doors to unique microfluidic phenomena, biomaterial flows and complex biosystems mimicking.

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Arvind Arun Dev, Thomas Hermans, Bernard Doudin. 2024-08-06. Ultra-soft liquid-ferrofluid interfaces. https://arxiv.org/abs/2408.03392

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