Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamics of a reactive spherical particle falling in a linearly
  stratified fluid   Motivated by numerous geophysical applications, we have carried out
laboratory experiments of a reactive (i.e. melting) solid sphere freely falling
by gravity in a stratified environment, in the regime of large Reynolds ($Re$)
and Froude numbers. We compare our results to non-reactive spheres in the same
regime. First, we confirm for larger values of $Re$, the stratification drag
enhancement previously observed for low and moderate Re (Magnaudet and Mercier,
2020). We also show an even more significant drag enhancement due to melting,
much larger than the stratification-induced one. We argue that the mechanism
for both enhancements is similar, due to the specific structure of the
vorticity field sets by buoyancy effects and associated baroclinic torques, as
deciphered for stratification by Zhang et al. (2019). Using particle image
velocimetry, we then characterize the long-term evolution (at time $t \gg 1/N$
with $N$ the Br\"unt-V\"ais\"al\"a frequency) of the internal wave field
generated by the wake of the spheres. Measured wave field is similar for both
reactive and inert spheres: indeed, each sphere fall might be considered as a
quasi impulsive source of energy in time and the horizontal direction, as the
falling time (resp. the sphere radius) is much smaller than $N$ (resp. than the
tank width). Internal gravity waves are generated by wake turbulence over a
broad spectrum, with the least damped component being at the
Br\"unt-V\"ais\"al\"a frequency and the largest admissible horizontal
wavelength. About 1% of the initial potential energy of each sphere is
converted in to kinetic energy in the internal waves, with no significant
dependence on the Froude number over the explored range.

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The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
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The categories of this paper are: eess
37
The categories of this paper are: supr-con
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The categories of this paper are: math
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th