Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Flowing System Gasdynamics. Part 3: Saint-Venant - Wantzel formula
  modern form   The modern form of the Saint-Venant - Wantzel formula for an outflow velocity
of gas stream from flowing element is submitted. Taking into account of contact
interaction of gas stream with the streamline surface in the form of the static
head law has allowed to find the spatial-energy liaison in flowing system. The
physically correct combination of mechanics of contact interaction and
thermodynamics of fluid medium in one formula has allowed simultaneously to be
liberated from the velocity coefficient and the discharge coefficient and
polytropic process. In the new form the formula has gained the key character
for computation of parameters of motion and state of gas stream in the flowing
system.

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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: eess