Physics of Fluids,
Год журнала:
2024,
Номер
36(11)
Опубликована: Ноя. 1, 2024
This
paper
presents
an
experimental
investigation
of
flow-induced
vibration
characteristics
cut-corner
prisms
with
various
aspect
ratios
(H*
=
1.0–13.33).
Experiments
were
conducted
in
a
recirculating
wind
tunnel
Reynolds
numbers
ranging
from
2651
to
7953,
based
on
the
prism's
side
length.
Four
prism
types
(square,
PS
0.2D,
0.5D,
and
0.8D,
where
is
length
parallel
incoming
flow)
exhibited
five
distinct
modes
as
speed
increased:
vortex-induced
(VIV),
transition
VIV
galloping,
pure
separated
weak
VIV-like
coupled
galloping.
Compared
square
prism,
mode
galloping
at
higher
ratios.
As
H*
increases,
end
effects
diminish,
resulting
more
concentrated
vortex
shedding
disappearance
splitting.
The
transitions
2S
(two
single
vortices
shed
per
cycle)
2
P
pairs
cycle).
Additionally,
largest
amplitude
0.8D
0.5D.
Unilateral
close-view
particle
image
velocimetry
results
show
that
decreases,
shear
layer
stretched
away
rear
due
effects,
altering
interaction
between
causing
modes.
study
provides
valuable
insights
for
optimizing
design
piezoelectric
energy
harvesters.
Physics of Fluids,
Год журнала:
2022,
Номер
34(11)
Опубликована: Окт. 19, 2022
The
flow-induced
transverse
vibration
of
a
cylinder
(diameter
D*)
with
an
attached
flexible
and
elastic
plate
high
aspect
ratio
to
its
leeward
side
is
investigated
numerically
at
low
Reynolds
number
150
for
range
reduced
velocities
(Ur)
using
in-house
developed
fluid
solver
based
on
curvilinear
immersed
boundary
method
strongly
coupled
open-source
finite
element-based
structural
solver.
It
was
observed
that
width
B=B*/D*=0.1
length
L=L*/D*=1
suppresses
large
vibrations
the
cylinder,
but
one
L
=
2,
contrary
previous
studies,
amplifies
up
five
times
isolated
cylinder.
Three
regimes
were
observed:
vortex-induced
(VIV),
suppression,
galloping.
In
VIV
regime
3≤Ur≤7,
lock-in
where
vortex
shedding
frequency
from
plate-cylinder
system
seen
slightly
increase
relative
static
cylinder–plate
match
natural
plate.
this
regime,
deformations
(max.
91%
L)
in
modes
(up
fifth
mode),
leading
new
patterns.
displacement
found
reach
nearly
twice
regime.
For
7<Ur≤9,
pushed
into
suppression
wherein
nullified
because
lack
vorticity
interaction
out-of-phase
deformation.
Beyond
Ur
9,
vibrated
galloping
it
shed
generated
forces
as
asymmetric
body
creating
angle
attack
incoming
flow.
primary
mode
deformation
progressively
increased
second
third
showed
linear
velocity
until
18.
amplitude
higher
more
intense
(higher
mode)
New
patterns
ranging
2S
till
2T
including
all
pattern
between
them
like
2S,
2P,
2Q,
P
+
T
modes,
which
are
reported
first
time.
