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arXiv · 1207.0110

Bulk elastic fingering instability in Hele-Shaw cells

Baudouin Saintyves·Olivier Dauchot·Elisabeth Bouchaud
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Abstract

We demonstrate experimentally the existence of a purely elastic fingering instability which arises when air penetrates into an elastomer confined in a Hele-Shaw cell. Fingers appear sequentially and propagate within the bulk of the material as soon as a critical strain, independent of the elastic modulus, is exceeded. Their width depends non-linearly on the distance between the confining glass plates. A key element in the driving force of the instability is the adhesion of layers of gels to the plates, which results in a considerable expense of elastic energy during the growth of the air bubble.

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Baudouin Saintyves, Olivier Dauchot, Elisabeth Bouchaud. 2012-06-30. Bulk elastic fingering instability in Hele-Shaw cells. https://doi.org/10.1103/physrevlett.111.047801

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