Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(4)
Published: April 1, 2024
Sediment
movements
on
the
riverbeds
are
crucial
in
fluvial
processes.
Therefore,
studying
incipient
sediment
motion
is
valuable
for
predicting
changes
behavior.
In
this
study,
influence
of
aquatic
vegetation
introduced
into
momentum
balance
equation
under
condition
a
bare
bed.
The
presented
model
open
channels
covered
by
derived,
consideration
density
and
relative
submergence.
This
study
simplifies
format.
its
coefficients
demonstrate
good
applicability
to
various
working
conditions
without
requiring
numerous
changes.
predicted
velocity
determined
proposed
validated
against
experimental
data.
Results
show
excellent
agreement
between
two
scenarios,
including
combinations
rigid
or
flexible
submerged
emergent
states.
Additionally,
observed
decrease
with
increasing
density.
However,
further
increase
may
amplify
resistance,
hindering
motion.
Meanwhile,
movement
becomes
challenging
as
water
depth
increases,
assuming
that
flow
discharge
remain
constant.
Water Resources Research,
Journal Year:
2024,
Volume and Issue:
60(5)
Published: May 1, 2024
Abstract
Widely
distributed
in
natural
rivers
and
coasts,
vegetation
interacts
with
fluid
flows
sediments
a
variable
complicated
manner.
Such
interactions
make
it
difficult
to
predict
associated
drag
forces
during
sediment
transport.
This
paper
investigates
the
coefficient
for
an
emergent
vegetated
patch
area
under
nonuniform
flow
mobile
bed
conditions,
based
on
analytical
model
solving
momentum
equation
following
our
previous
work
(Zhang
et
al.,
2020,
https://doi.org/10.1029/2020WR027613
).
Emergent
was
modeled
rigid
cylinders
arranged
staggered
arrays
of
different
coverage
∅.
Laboratory
flume
tests
were
conducted
measure
variations
both
water
surfaces
along
sand
bed.
Based
experimental
theoretical
analyses,
dimensionless
integrating
terms
properties
effects
is
proposed
C
d
over
The
calculated
values
exhibit
two
trends,
that
is,
nonmonotonically
or
monotonically
increasing
streamwise
direction,
due
combined
effect
surface
gradient
slope.
morphodynamic
response
manifests
as
evolution
slope
within
patch.
Ongoing
scouring
directs
flow's
energy
toward
overcoming
rising
slope,
leading
relatively
stable
stage
low
transport
rate.
study
advances
existing
understanding
coefficient's
role
flows.
It
also
enhances
applicability
models
riverine
restoration.
Proceedings of the Institution of Civil Engineers - Water Management,
Journal Year:
2021,
Volume and Issue:
175(2), P. 55 - 66
Published: July 6, 2021
This
study
achieved
three
goals
to
clarify
the
impact
of
a
vegetation
patch
on
flow
adjustment
and
velocity.
First,
valid
equation
for
interior
distance
(L
d
)
inside
model
was
developed
wide
range
velocities
depths.
Second,
minimum
beyond
which
resuspension
fine
sediment
is
suppressed
min
found
be
related
position
at
local
velocity
decreases
threshold
generating
stem-scale
turbulence.
L
primarily
depends
blockage
(C
ab)
stem
diameter
(d):
shorter
result
larger
C
ab
smaller
d.
An
formulated
estimating
.
Third,
fully
region
>
x
),
an
estimate
increase
in
mean
bare
channel
relative
overall
For
<
2,
this
fraction
controlled
by
both
density
(ad)
(b/B)
whereas,
only
b/B.
A
suggestion
choosing
size
future
research
projects
presented.
Geophysical Research Letters,
Journal Year:
2021,
Volume and Issue:
48(21)
Published: Oct. 17, 2021
Abstract
Vegetation
provides
habitat
and
nature‐based
solutions
to
coastal
flooding
erosion,
drawing
significant
interest
in
its
restoration,
which
requires
an
understanding
of
sediment
transport
retention.
Laboratory
experiments
examined
the
influence
stem
diameter
arrangement
on
bedload
by
considering
arrays
different
mixed
diameters.
Bedload
rate
was
observed
depend
turbulent
kinetic
energy,
with
no
dependence
diameter,
shown
be
consistent
impulse
model
for
entrainment.
Existing
predictors
bare
beds,
based
bed
shear
stress,
were
recast
terms
turbulence.
The
new
turbulence‐based
predicted
measured
canopies
across
a
range
conditions
drawn
from
several
previous
studies.
A
prediction
turbulence
biomass
velocity
also
described,
providing
important
step
toward
predicting
real
vegetation
morphology.
Journal of Fluid Mechanics,
Journal Year:
2022,
Volume and Issue:
947
Published: Aug. 25, 2022
Abstract
In
this
study,
we
present
a
three-dimensional
numerical
model
for
the
interaction
of
flow
with
submerged
flexible
vegetation,
based
on
large-eddy
simulation
and
immersed
boundary
method.
The
innovatively
realises
between
highly
vegetation
clustered
leaves.
Besides
being
motion
full
degrees
freedom,
study
improves
consideration
in
all
directions,
addition
energy
momentum
transfer
spanwise
direction.
Furthermore,
perform
flume
experiment
results
which
are
used
to
validate
effects
model.
It
is
found
that
can
effectively
simulate
velocity
profiles
movement
induced
by
flow.
Using
analyse
flow–vegetation
interaction,
find
closely
related
velocity.
As
increases,
both
offset
angle
swaying
amplitude
increase.
Compared
vertical
rigid
tilting
does
not
significantly
change
difference
magnitude
turbulent
kinetic
inside
outside
canopy,
but
it
weaken
disturbance
flow,
thus
reducing
resistance
However,
dose
increase
canopy.
forms
Kelvin–Helmholtz
hairpin
vortices
intensifying
turbulence
production,
enhancing
Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(5)
Published: May 1, 2024
Vortices
are
generated
across
a
wide
range
of
scales
due
to
the
interaction
between
in-stream
vegetation
and
surrounding
flows,
significantly
influencing
hydro-geomorphodynamics
in
earth
surface
water
systems.
Recent
advance
patch
hydrodynamics
has
revealed
that
elongation
middle
channel
can
generate
complex
wake
flow
patterns
by
adjusting
bleed
from
triggering
patch-edge
Kelvin–Helmholtz
(KH)
vortices.
With
broader
experimental
configurations,
this
study
reveals
how
mixing
is
apparently
strengthened
presence
KH
vortices,
indicated
larger
steady
velocity,
shorter
length,
damped
energy
von
Karman
vortex.
Furthermore,
we
quantify
these
characteristic
metrics
behavior
with
without
influence
Our
findings
provide
insights
into
role
vegetation-induced
vortex
interactions
regulating
processes,
thereby
promoting
informed
practices
environmental
flows.
Journal of Fluid Mechanics,
Journal Year:
2022,
Volume and Issue:
951
Published: Nov. 11, 2022
Submerged
flexible
vegetation
occupies
the
core
of
aquatic
ecosystem
research.
Hydrodynamics
submerged
and
its
interaction
with
flow
in
an
open
channel
are
great
significance
studying
mass
momentum
transports
flow.
In
this
study,
a
numerical
model
for
highly
based
on
large
eddy
simulation
immersed
boundary
method
was
used
to
simulate
flow–vegetation
interaction.
It
is
recognised
that
alternate
vortices
opposite
sense
rotations
appear
at
interface.
These
prompt
canopy
have
wave-like
coherent
waving
motion,
commonly
called
monami
phenomena.
The
spatial
scale
spreading
velocity
streamwise
direction
these
determine
wavelength,
frequency
amplitude
motion.
fast
Fourier
transform
applied
analyse
factors
affecting
characteristics
revealed
that,
as
increases,
wavelength
motion
decreases,
while
increase.
Besides,
spacing
increase,
but
decreases.
Furthermore,
increase
relative
density
magnifies
without
frequency.
Water Resources Research,
Journal Year:
2024,
Volume and Issue:
60(7)
Published: July 1, 2024
Abstract
Investigations
of
water
flow
movements
affected
by
vegetation
is
a
research
hotspot
in
ecological
restoration.
The
theory
and
equations
the
velocity
distribution
under
influence
rigid
are
relatively
mature.
This
study
proposes
new
drag
force
equation
that
varies
with
bending
angle
analytical
solution
profile.
Comparisons
between
model
calculation
experimental
data,
results
showed
this
proposed
produced
accurate
simulations
for
through
flexible
various
deflections.
In
addition,
was
verified
to
be
applicable
without
angle.
Moreover,
features
parameters
adopted
discussed,
empirical
these
presented.
further
improves
field
environmental
fluid
mechanics
can
serve
as
theoretical
underpinning
restoration
river
courses.
Journal of Ecohydraulics,
Journal Year:
2025,
Volume and Issue:
unknown, P. 1 - 19
Published: Jan. 16, 2025
The
flow
dynamics
and
river
geomorphology
are
influenced
by
vegetation
patches,
which
naturally
exist
in
various
patterns.
Previous
studies
have
not
explored
the
effect
of
patches
with
different
shapes
placed
a
staggered
arrangement
varying
aspect
ratio
(AR:
longitudinal
to
lateral
patch
length).
We
used
numerical
method
examine
around
rigid,
emerged
rectangular
flume.
impact
(circle,
square,
rectangle)
was
investigated
using
Computational
Fluid
Dynamics
(CFD)
software
FLUENT.
findings
indicate
decrease
mean
streamwise
velocity
downstream
while
relaxation
occurs
alternate
(free)
regions.
significantly
affected
shape
circular
configuration
offering
maximum
resistance.
Vortex
shedding,
including
primitive
Kármán
vortex
(PKV)
large-scale
(LKV)
streets,
behind
found
be
strong
prominent
first
for
then
(with
AR
=
2)
shapes.
Flow
through
2
appeared
more
uniform
higher
efficiency
reduction
than
that
0.5.
this
research
helpful
assessing
structure
vegetation.
