A
large
amount
of
vegetation
in
nature
exists
the
form
heterogeneous
patches,
and
variations
characteristics
significantly
affect
water
flow
structures.
The
objective
this
study
is
to
investigate
effect
alternating
sparse
dense
patches
on
turbulence
characteristics.
Multiple
sets
scenarios
were
designed
for
numerical
simulation
analysis,
a
comparison
was
made
with
homogeneous
vegetation.
Results
indicate
that
compared
vegetation,
arrangement
alters
distribution
velocities
zone
main
channel,
promoting
material
exchange
between
these
regions.
density
difference
channel
increases
larger
differences,
but
magnitude
limited
generally
remains
within
10%
width.
In
balance
equation
turbulent
kinetic
energy,
terms
are
influenced
differently
by
changes
density.
As
increases,
convective
term
gradually
while
production
diffusion
exhibit
“lower
middle,
higher
at
both
ends”
pattern.
dissipation
demonstrates
reduction
low-density
ultimately
exhibits
an
amplification
effect.
Furthermore,
determines
using
data
from
mid-height
represent
entire
cross
section
may
result
maximum
error
up
11%.
Environmental Science and Ecotechnology,
Год журнала:
2024,
Номер
21, С. 100429 - 100429
Опубликована: Май 10, 2024
In-channel
vegetation
is
ubiquitous
in
aquatic
environments
and
plays
a
critical
role
the
fate
transport
of
solutes
particles
ecosystems.
Recent
studies
have
advanced
our
understanding
solute
flow
particle
This
review
summarizes
these
papers
discusses
impacts
emergent
rigid
on
surface
flow,
advection
dispersion
solutes,
suspended
load
transport,
bedload
hyporheic
exchange.
The
two
competing
effects
above
processes
are
discussed.
On
one
hand,
reduces
mean
velocity
at
same
slope,
which
mass
transport.
other
velocity,
generates
turbulence,
enhances
Mechanistic
predictive
equations
derived
from
laboratory
experiments
Predictive
for
turbulent
kinetic
energy
inside
an
canopy
based
force
balance.
advection-dispersion
process,
exchange
summarized.
vegetation-related
factors,
such
as
morphology,
submergence,
flexibility,
briefly
transporting
particles,
micro-
macro-plastics,
also
Finally,
suggestions
future
research
directions
proposed
to
advance
dynamic
interplays
among
natural
vegetation,
dynamics,
sedimentary
processes.
Aquatic
plants
play
a
crucial
role
in
the
hydrodynamic
and
material
transport
processes
within
aquatic
environments
due
to
additional
flow
resistance
induced
by
vegetation
stems.
In
this
study,
high-resolution
numerical
experiments
were
performed
investigate
drag
characteristics
of
circular
patches
fully
immersed
turbulent
open
channel
flow.
The
submerged
patch
was
modeled
as
rigid
cylinder
array
with
diameter
D
composed
N
elements
d.
effects
density
Φ
(0.023
≤
1)
relative
d/D
(d/D
=
0.051
0.072)
tested.
simulation
results
show
that
affect
exerted
modifying
bleeding
intensity.
With
increase
Φ,
forces
acting
on
individual
decrease,
whereas
total
increase.
oscillation
strength
force
cylinders
depends
fixed
positions
patch.
presence
free
end
leads
enhanced
wake
entrainment
Φ.
coefficient
is
smaller
than
emergent
when
dimensionless
frontal
area
aD
>
3.
However,
two
exhibit
comparable
coefficients
for
values.
Bank
angle
and
floodplain
vegetation
emergence
determine
the
flow
nature
in
a
compound
channel.
Two
sets
of
45°
90°
bank
channel
is
considered
present
work.
Each
set
considers
three
cases
arrangements:
no
vegetation,
multi-layered
fully
submerged,
partially
emergent.
The
characteristics
like
velocity,
Reynolds
shear
stress
(RSS),
turbulent
kinetic
energy
(TKE)
do
not
vary
much
cross
section
absence
vegetation.
However,
with
slopes
nearby
region
are
affected
most
as
it
acts
an
intermediary
between
main
floodplain.
An
analysis
anisotropic
invariant
map
shows
dominance
transverse
component
compared
to
velocity
around
higher
for
steep
(90°)
gradual
slope
(45°)
streamwise
RSS
bursting
events
also
show
magnitude
near
bed
sloping
region.
This
indicates
instability
banks
slopes.
increase
affects
TKE
greater
vulnerability
presence
emergence.
From
hydraulic
engineering
perspective,
this
study
will
be
helpful
field
understanding
failure
ways
maintain
their
stability.
A
large
amount
of
vegetation
in
nature
exists
the
form
heterogeneous
patches,
and
variations
characteristics
significantly
affect
water
flow
structures.
The
objective
this
study
is
to
investigate
effect
alternating
sparse
dense
patches
on
turbulence
characteristics.
Multiple
sets
scenarios
were
designed
for
numerical
simulation
analysis,
a
comparison
was
made
with
homogeneous
vegetation.
Results
indicate
that
compared
vegetation,
arrangement
alters
distribution
velocities
zone
main
channel,
promoting
material
exchange
between
these
regions.
density
difference
channel
increases
larger
differences,
but
magnitude
limited
generally
remains
within
10%
width.
In
balance
equation
turbulent
kinetic
energy,
terms
are
influenced
differently
by
changes
density.
As
increases,
convective
term
gradually
while
production
diffusion
exhibit
“lower
middle,
higher
at
both
ends”
pattern.
dissipation
demonstrates
reduction
low-density
ultimately
exhibits
an
amplification
effect.
Furthermore,
determines
using
data
from
mid-height
represent
entire
cross
section
may
result
maximum
error
up
11%.
