Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vortical and Self-similar Flows of 2D Compressible Euler Equations   This paper presents the vortical and self-similar solutions for 2D
compressible Euler equations using the separation method. These solutions
complement Makino's solutions in radial symmetry without rotation. The
rotational solutions provide new information that furthers our understanding of
ocean vortices and reference examples for numerical methods. In addition, the
corresponding blowup, time-periodic or global existence conditions are
classified through an analysis of the new Emden equation. A conjecture
regarding rotational solutions in 3D is also made.

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The categories of this paper are: plasm-ph
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The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
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The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex