Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermal Rayleigh-Marangoni convection in a three-layer
  liquid-metal-battery model   The combined effects of buoyancy-driven Rayleigh-B\'{e}nard convection (RC)
and surface tension-driven Marangoni convection (MC) are studied in a
triple-layer configuration which serves as a simplified model for a liquid
metal battery (LMB). The three-layer model consists of a liquid metal alloy
cathode, a molten salt separation layer, and a liquid metal anode at the top.
Convection is triggered by the temperature gradient between the hot electrolyte
and the colder electrodes, which is a consequence of the release of resistive
heat during operation. We present a linear stability analysis of the state of
pure thermal conduction in combination with three-dimensional direct numerical
simulations of the nonlinear turbulent evolution on the basis of a
pseudospectral method. Five different modes of convection are identified in the
configuration, which are partly coupled to each other: RC in the upper
electrode, RC with internal heating in the molten salt layer, MC at both
interfaces between molten salt and electrode as well as anti-convectionin the
middle layer and lower electrode. The linear stability analysis confirms that
the additional Marangoni effect in the present setup increases the growth rates
of the linearly unstable modes, i.e. Marangoni and Rayleigh-B\'{e}nard
instability act together in the molten salt layer. The critical Grashof and
Marangoni numbers decrease with increasing middle layer thickness. The
calculated thresholds for the onset of convection are found for realistic
current densities of laboratory-sized LMBs. The global turbulent heat transfer
follows scaling predictions for internally heated RC. The global turbulent
momentum transfer is comparable with turbulent convection in the classical
Rayleigh-B\'{e}nard case.

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The categories of this paper are: eess
26
The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
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The categories of this paper are: nlin
10
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: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
2
The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph