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arXiv · 1402.5883

Microrheology close to an equilibrium phase transition

J. Reinhardt·A. Scacchi·J. M. Brader
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Abstract

We investigate the microstructural and microrheological response to a tracer particle of a two- dimensional colloidal suspension under thermodynamic conditions close to a liquid-gas phase bound- ary. On the liquid side of the binodal, increasing the velocity of the (repulsive) tracer leads to the development of a pronounced cavitation bubble, within which the concentration of colloidal parti- cles is strongly depleted. The tendency of the liquid to cavitate is characterized by a dimensionless colloidal cavitation number. On the gas side of the binodal, a pulled (attractive) tracer leaves behind it an extended trail of colloidal liquid, arising from downstream advection of a wetting layer on its surface. For both situations the velocity dependent friction is calculated.

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J. Reinhardt, A. Scacchi, J. M. Brader. 2014-02-24. Microrheology close to an equilibrium phase transition. https://doi.org/10.1063/1.4870497

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