Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lattice Boltzmann simulations of capillary filling: finite vapour
  density effects   Numerical simulations of two-dimensional capillary filling using the
pseudo-potential lattice Boltzmann model for multiphase fluids are presented,
with special emphasis on the role of finite-vapour density effects. It is shown
that whenever the density of the light-phase exceeds about ten percent of the
dense phase, the front motion proceeds through a combined effect of capillary
advection and condensation. As a result, under these conditions, the front
proceeds at a higher speed as compared to the Washburn prediction. It is
suggested that such an acceleration effect might be observed in experiments
performed sufficiently close to critical conditions

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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: econ
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
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The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio
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The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: quant-ph