Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modelling large scale airgun-bubble dynamics with highly non-spherical
  features   A thorough understanding of the dynamics of meter-sized airgun-bubbles is
very crucial to seabed geophysical exploration. In this study, we use the
boundary integral method to investigate the highly non-spherical airgun-bubble
dynamics and its corresponding pressure wave emission. Moreover, a model is
proposed to also consider the process of air release from the airgun port,
which is found to be the most crucial factor to estimate the initial peak of
the pressure wave. The numerical simulations show good agreement with
experiments, in terms of non-spherical bubble shapes and pressure waves.
Thereafter, the effects of the port opening time $T\rm_{open}$, airgun firing
depth, heat transfer, and gravity are numerically investigated. We find that a
smaller $T\rm_{open}$ leads to a more violent air release that consequently
causes stronger high-frequency pressure wave emissions; however, the
low-frequency pressure waves are little affected. Additionally, the
non-spherical bubble dynamics is highly dependent on the Froude number $Fr$.
Starting from $Fr=2$, as $Fr$ increases, the jet contains lower kinetic energy,
resulting in a stronger energy focusing of the bubble collapse itself and thus
a larger pressure peak during the bubble collapse phase. For $Fr \ge 7$, the
spherical bubble theory becomes an appropriate description of the
airgun-bubble. The new findings of this study may provide a reference for
practical operations and designing environmentally friendly airguns in the near
future.

12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph