Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The clustering morphology of freely rising deformable bubbles   We investigate the clustering morphology of a swarm of freely rising
deformable bubbles. A three-dimensional Vorono\"i analysis enables us to
quantitatively distinguish between two typical clustering configurations:
preferential clustering and a grid-like structure. The bubble data is obtained
from direct numerical simulations (DNS) using the front-tracking method. It is
found that the bubble deformation, represented by the aspect ratio \chi, plays
a significant role in determining which type of clustering is realized: Nearly
spherical bubbles with \chi <~ 1.015 form a grid-like structure, while more
deformed bubbles show preferential clustering. Remarkably, this criteria for
the clustering morphology holds for different diameters of the bubbles, surface
tension, and viscosity of the liquid in the studied parameter regime. The
mechanism of this clustering behavior is connected to the amount of vorticity
generated at the bubble surfaces.

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The categories of this paper are: cs
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The categories of this paper are: patt-sol
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: plasm-ph
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The categories of this paper are: math