The Astrophysical Journal,
Год журнала:
2024,
Номер
975(1), С. 118 - 118
Опубликована: Окт. 29, 2024
Abstract
This
study
investigated
the
mechanisms
of
vorticity
generation
and
role
vortex
tubes
in
plasma
heating
energy
transport.
Vortex
were
identified
using
instantaneous
deviation
technique
MURaM
data
set
a
simulated
solar
plage
region
photosphere.
Within
3D
kinetic
tubes,
misalignment
magnetic
pressure
inverse
density
gradient,
rather
than
baroclinic
effects,
primarily
drive
within
tubes.
During
their
lifetime,
vortices
become
less
dense
as
Lorentz
force
pushes
outwards
against
gradients.
In
upper
photosphere,
contributes
to
adiabatic
cooling
by
expanding
or
compressing
around
turn,
motion
affects
field,
enhancing
current
intensifying
force,
which
may
further
increase
heating.
Moreover,
our
results
confirm
that
can
significantly
boost
viscous
ohmic
on
intergranular
scales
They
generate
more
energy,
with
transport
Poynting
flux
notably
nonuniform
dominant
at
boundaries.
creates
circulation
net
upwards
enhance
chromospheric
support
temperatures.
The Astrophysical Journal,
Год журнала:
2024,
Номер
963(1), С. 10 - 10
Опубликована: Фев. 21, 2024
Abstract
The
nature
of
energy
generation,
transport,
and
effective
dissipation
responsible
for
maintaining
a
hot
solar
upper
atmosphere
is
still
elusive.
Poynting
flux
vital
parameter
describing
the
direction
magnitude
flow,
which
mainly
used
in
physics
estimating
upward
generated
by
photospheric
plasma
motion.
This
study
presents
pioneering
3D
mapping
magnetic
transport
within
numerically
simulated
atmosphere.
By
calculating
Finite
Time
Lyapunov
Exponent
velocity,
defined
as
ratio
to
density,
we
precisely
identify
sources
destinations
flow
throughout
reveals
presence
barriers
lower
atmosphere,
restricting
amount
from
photosphere
reaching
chromosphere
corona.
Interacting
kinematic
vortices
create
channels,
breaking
through
these
allowing
three
times
more
input
motions
reach
than
before
formed.
vortex
system
also
substantially
alters
mapping,
acting
source
deposition
energy,
leading
localized
concentration.
Furthermore,
our
results
show
that
transported
following
vortical
motion:
vortex.
In
regions
where
coexist,
they
favor
conditions
ohmic
viscous
heating,
since
naturally
large
gradients
velocity
fields
over
small
spatial
scales.
Hence,
promotes
local
temperatures
around
million
Kelvins.
The Astrophysical Journal,
Год журнала:
2023,
Номер
949(1), С. 8 - 8
Опубликована: Май 1, 2023
Abstract
In
solving
the
solar
coronal
heating
problem,
it
is
crucial
to
comprehend
mechanisms
by
which
energy
conveyed
from
photosphere
corona.
Recently,
magnetic
tornadoes,
characterized
as
coherent,
rotating
magnetic-field
structures
extending
corona,
have
drawn
growing
interest
a
possible
means
of
efficient
transfer.
Despite
its
acknowledged
importance,
underlying
physics
tornadoes
remains
elusive.
this
study,
we
conduct
three-dimensional
radiative
magnetohydrodynamic
simulation
that
encompasses
upper
convective
layer
and
extends
into
with
view
investigating
how
are
generated
efficiently
transfer
We
find
single
event
flux
concentration
merger
on
gives
rise
formation
tornado.
The
Poynting
transferred
corona
found
be
four
times
greater
in
presence
tornado,
compared
absence.
This
increase
attributed
reduction
loss
chromosphere,
resulting
weakened
magnetic-energy
cascade.
Based
an
evaluation
fraction
merging
events,
our
results
suggest
contribute
approximately
50%
regions
where
strength
10
G.
Potentially,
contribution
could
even
areas
stronger
field.
Astronomy and Astrophysics,
Год журнала:
2024,
Номер
692, С. A71 - A71
Опубликована: Окт. 18, 2024
Parker
Solar
Probe's
(PSP)
discovery
of
the
prevalence
switchbacks
(SBs),
localised
magnetic
deflections
in
nascent
solar
wind,
has
sparked
interest
uncovering
their
origins.
A
prominent
theory
suggests
these
SBs
originate
lower
corona
through
reconnection
processes,
closely
linked
to
jet
phenomena.
Jets
are
impulsive
events,
observed
across
scales
and
atmosphere
layers,
associated
with
release
twist
helicity.
This
study
examines
whether
self-consistent
jets
can
form
propagate
into
super-Alfv\'enic
assesses
impact
distinct
wind
profiles
on
dynamics,
determines
if
jet-induced
untwisting
waves
display
signatures
typical
SBs.
We
employed
parametric
3D
numerical
MHD
simulations
using
ARMS
code
model
generation
jets.
Our
focuses
propagation
atmospheric
plasma
$\beta$
Alfv\'en
velocity
profiles,
including
a
wind.
findings
show
that
coronal
Notable
structures
such
as
leading
Alfv\'enic
wave
trailing
dense-jet
region
were
consistently
diverse
atmospheres.
The
dynamics
significantly
influenced
by
variations,
changes
affecting
group
ratio
structures.
U-loops,
prevalent
at
onset,
do
not
persist
low-$\beta$
corona,
but
SB-like
signatures.
However,
full-reversal
observed.
These
may
explain
absence
full
reversal
sub-Alfv\'enic
illustrate
jet-like
shedding
light
possible
SB
formation
processes.
The
rapid
pace
of
urbanization
across
the
globe
has
led
to
proliferation
various
urban
infrastructure.
They
generate
aerodynamic
noise,
posing
significant
challenges
planning
and
residents'
comfort.
Despite
Lighthill's
mathematical
analogy,
current
noise
control
applications
rely
heavily
on
wind
tunnel
tests
computer
simulations.
Physical
mechanisms
behind
aeroacoustic
have
yet
be
validated
elucidated
experimentally.
This
work
observed
geometry
sound-activated
vortices
determined
their
streamline
velocity
distribution.
theoretical
results
are
consistent
with
experimental
observations,
offering
a
kinematic
model
for
sound
activated
vortices.
experimentally
improves
understanding
provides
development
strategies.
The Astrophysical Journal,
Год журнала:
2025,
Номер
979(1), С. 27 - 27
Опубликована: Янв. 15, 2025
Abstract
Swirl-shaped
flow
structures
have
been
observed
throughout
the
solar
atmosphere,
in
both
emission
and
absorption,
at
different
altitudes
locations,
are
believed
to
be
associated
with
magnetic
structures.
However,
distribution
patterns
of
such
swirls,
especially
their
spatial
positions,
remain
unclear.
Using
Automated
Swirl
Detection
Algorithm,
we
identified
swirls
from
high-resolution
photospheric
observations,
centered
on
Fe
i
630.25
nm,
a
quiet
region
near
Sun's
central
meridian
by
Swedish
1-m
Solar
Telescope.
Via
detailed
study
locations
detected
small-scale
an
average
radius
~300
km,
found
that
most
them
located
lanes
between
mesogranules
(which
diameter
~5.4
Mm)
instead
commonly
intergranular
lanes.
The
squared
rotation,
expansion/contraction
vector
speeds,
proxy
kinetic
energy
all
follow
Gaussian
distributions.
Their
rotation
speed,
circulation
positively
correlated
radius.
All
these
results
suggest
scales
across
observational
56
.″
5
×
57
field
view
could
share
same
triggering
mechanism
preferred
scales.
A
comparison
our
previous
work
suggests
number
is
local
concentrations,
stressing
again
close
relation
concentrations:
should
correlate
strength
concentrations.
Journal of Fluid Mechanics,
Год журнала:
2025,
Номер
1009
Опубликована: Апрель 21, 2025
We
propose
an
analytical
approach
based
on
the
Frenet–Serret
(FL)
frame
field,
where
FL
and
corresponding
curvature
torsion
are
defined
at
each
point
along
magnetic
field
lines,
to
investigate
evolution
of
tubes
their
interaction
with
vortex
in
magnetohydrodynamics.
Within
this
framework,
simplified
expressions
for
Lorentz
force,
its
curl,
dynamics
flux
helicity
derived.
further
perform
direct
numerical
simulations
linkage
between
effect
initial
angle
$\theta$
,
ranging
from
$0^{\,\circ}$
$45^{\,\circ}$
evolution.
Our
results
show
that
non-zero
generate
forces,
which
turn
produce
dipole
vortices.
These
vortices
lead
splitting
into
smaller
structures,
releasing
energy.
Both
exhibit
quasi-Lagrangian
behaviour,
maintaining
similar
shapes
during
consistent
relative
positions
over
time.
A
tube
strength
comparable
tube,
kinetic
energy
induced
by
is
same
order
as
can
inhibit
disrupting
formation
dipoles.
Additionally,
minor
variations
angular
configuration
significantly
influence
large-scale
flow
structures.
