Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Life stages of wall-bounded decay of Taylor-Couette turbulence   The decay of Taylor-Couette turbulence, i.e~the flow between two coaxial and
independently rotating cylinders, is numerically studied by instantaneously
stopping the forcing from an initially statistically stationary flow field at a
Reynolds number of $Re=3.5\times 10^4$. The effect of wall-friction is analysed
by comparing three separate cases, in which the cylinders are either suddenly
made no-slip or stress-free. Different life stages are observed during the
decay. In the first stage, the decay is dominated by large-scale rolls.
Counterintuitively, when these rolls fade away, if the flow inertia is small a
redistribution of energy occurs, the energy of the azimuthal velocity behaves
non-monotonically: first decreasing by almost two orders of magnitude, and then
increasing during the redistribution. The second stage is dominated by
non-normal transient growth of perturbations in the axial (spanwise) direction.
Once this mechanism is exhausted, the flow enters the final life stage, viscous
decay, which is dominated by wall-friction. We show that this stage can be
modeled by a one-dimensional heat equation, and that self-similar velocity
profiles collapse onto the theoretical solution.

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The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
27
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: patt-sol
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The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: bayes-an
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-th
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The categories of this paper are: q-alg