Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inverse Saffman-Taylor experiments with particles lead to capillarity
  driven fingering instabilities   Using air to displace a viscous fluid contained in Hele-Shaw cell can create
a fingering pattern at the interface between the fluids, if the capillary
number exceeds a critical value. This Saffman-Taylor instability is revisited
for the inverse case of a viscous fluid displacing air, when partially wettable
hydrophilic particles are lying on the walls. Though the inverse case is
otherwise stable, the presence of the particles results in a fingering
instability at low capillary number. This capillary-driven instability is
driven-by the integration of particles into the interface which results from
the minimization of the interfacial energy. Both axisymmetric and rectangular
geometries are considered in order to quantify this phenomenon.

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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: eess