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arXiv · 2305.16417

Thin-Film-Mediated Deformation of Droplet during Cryopreservation

Jochem G. Meijer·Pallav Kant·Duco Van Buuren·Detlef Lohse
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Abstract

Freezing of dispersions is omnipresent in science and technology. While the passing of a freezing front over a solid particle is reasonably understood, this is not so for soft particles. Here, using an oil-in-water emulsion as a model system, we show that when engulfed into a growing ice front, a soft particle severely deforms. This deformation strongly depends on the engulfment velocity $V$, even forming pointy-tip shapes for low values of $V$. We find such singular deformations are mediated by interfacial flows in $\textit{nanometric}$ thin liquid films separating the non-solidifying dispersed droplets and the solidifying bulk. We model the fluid flow in these intervening thin films using a lubrication approximation and then relate it to the deformation sustained by the dispersed droplet.

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Jochem G. Meijer, Pallav Kant, Duco Van Buuren, Detlef Lohse. 2023-05-25. Thin-Film-Mediated Deformation of Droplet during Cryopreservation. https://doi.org/10.1103/physrevlett.130.214002

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