Floatover
method
has
been
widely
applied
in
the
installation
of
offshore
platforms,
which
advantages
high
efficiency,
economy,
and
large
lifting
capacity.
Few
studies
could
numerically
experimentally
simulate
continuous
load
transfer
process
shows
significant
nonstationary
characteristics.
This
paper
conducts
experimental
research
on
mating
floatover
system.
The
ballasting
system
based
control
logic
feedback
adjustment
is
developed
to
adjust
inertia
properties
vessel,
validation
tests
are
conducted
verify
feasibility
reliability
buffer
devices
designed
carefully
nonlinear
stiffnesses
elastic
cushion.
stationary
model
for
0%
100%
stages
established
tested
tests,
dynamic
responses
analyzed
by
using
statistical
spectral
methods
respectively.
Stationary
indicate
that
characteristics
distribution
values
LMU
(Leg
Mating
Unit)
loads
transverse
symmetric
positions
similar.
segmented
according
physical
process,
time-frequency
spectrum
piecewise
statistics
diagram
find
critical
stage.
Applied Ocean Research,
Год журнала:
2023,
Номер
141, С. 103757 - 103757
Опубликована: Окт. 19, 2023
In
this
work,
we
propose
numerical
validations
of
the
DeepCwind
semi-submersible
floating
platform
configuration
for
a
single
horizontal
axis
wind
turbine
using
data
from
two
experimental
testing
investigations.
A
Smoothed
Particle
Hydrodynamics
solver
is
employed
to
estimate
fluid
induced
loads,
whereas
mooring
connections
are
handled
via
an
external
library.
The
first
validation
setup
based
on
offshore
concept
moored
with
system
taut-lines
and
tested
free-decay
surge
heave
motion
(OC6-Phase
Ia).
damping
evaluation
yields
fair
estimation
behavior,
much
more
dissipation
experienced
surge.
second
features
full
hydrodynamic
characterization
frequency-related
load
patterns
by
three
different
sea-state
representations
(mono-,
bi-chromatic,
irregular
waves)
Ib).
model
accurately
matches
whole
spectrum
investigated
wave
components,
perfectly
capturing
non-linear
behavior
shown
considered
patterns.
This
work
concludes
systematic
study
response,
tension,
pressure
vorticity,
suggesting
that:
steepness
criterion
alone
cannot
identify
most
restrictive
case;
waves
spectral
characteristics
close
resonance
period
lead
higher
tensions
in
systems,
maximum
fluid-induced
loads
hull
decoupled
displacement
peaks,
showing
average
reduction
30%
respect
maxima;
very
steep
maximize
likelihood
overtopping
slamming
resulting
locally
overpressure
free-board
up
100%
than
expected
similar
heights
milder
profiles.
input
these
last
tests
released
sake
reproduction.
Physics of Fluids,
Год журнала:
2023,
Номер
35(11)
Опубликована: Ноя. 1, 2023
Renewable
energy
converters,
such
as
bio-inspired
fluttering
foils,
are
gaining
popularity
due
to
their
eco-friendly
properties.
However,
the
system
with
multiple
objects
has
received
scant
attention.
Here,
we
analyze
how
spacing
influences
transverse
(one-degree-of-freedom)
vortex-induced
vibration
of
two
tandem
identical
elliptic
cylinders
at
a
constant
Reynolds
number
by
employing
wide
range
reduced
velocities
(Ur∈[2,14])
and
space
ratios
(L∗∈[2,6]).
The
incompressible
Navier–Stokes
equations
solved
using
overset
mesh
method
in
OpenFOAM®
library.
findings
indicate
that
wake
structure
goes
through
eight
distinct
modes,
well
gap
flow
patterns
(reattachment
co-shedding).
Vibrational
responses,
force
parameters,
determine
three
configurations.
At
small
(L∗=2),
upstream
cylinder
(UC)
traditional
lock-in
(the
frequency
ratio
fy/fn≃0.95–1.05)
velocity
(Ur≃7),
downstream
(DC)
narrow
region
around
Ur≃9.
UC
soft-lock-in
synchronization
fy/fn≃1.15)
high
(Ur≃8–10).
vibrations
both
cylinders,
but
especially
DC,
reach
relatively
amplitudes.
moderate
(L∗=3),
bears
zone
analogous
single
same
mass
ratio,
while
DC
shows
vast
(Ur≃8–14).
large
(L∗=4,
5,
6),
amplitude
is
often
larger
than
when
it
region.
exhibits
peak
Ur
=
7
wake-galloping
for
>
12.
Journal of Marine Science and Engineering,
Год журнала:
2025,
Номер
13(5), С. 995 - 995
Опубликована: Май 21, 2025
In
recent
years,
the
twin-barge
float-over
method
has
been
widely
used
in
offshore
installations.
This
paper
conducts
numerical
simulation
and
experimental
research
on
installation
of
wind
turbines
(TBFOI-OWTs),
focusing
primarily
seakeeping
performance,
also
explores
influence
gap
distance
hydrodynamic
behavior
TBFOI-OWTs.
Model
tests
are
conducted
ocean
basin
at
Tsinghua
Shenzhen
International
Graduate
School.
A
physical
model
with
a
scale
ratio
1:50
is
designed
fabricated,
comprising
two
barges,
truss
carriage
frame,
small
turbines,
spread
catenary
mooring
system.
series
tests,
including
free
decay
regular
wave
random
carried
out
to
investigate
hydrodynamics
The
results
good
agreement,
thereby
validating
accuracy
method.
motion
RAOs
TBFOI-OWTs
small,
demonstrating
their
performance.
Compared
situation,
surge
sway
motions
waves
have
greater
ranges
amplitudes.
reveals
that
analysis
cannot
depend
only,
more
importantly,
nature
realistic
less
favorable
for
responses
controlled
by
motions’
natural
frequencies
incident
frequency.
It
revealed
between
barges
significant
beam
seas.
Within
certain
range
periods
(10.00
s
<
T
15.00
s),
increasing
reduces
RAO
roll
due
energy
dissipated
damping
pool
barge
gap.
For
safety
within
an
operating
window,
it
meaningful
but
challenging
accurate
predictions
forthcoming
motions.
this,
this
study
employs
Whale
Optimization
Algorithm
(WOA)
optimize
Long
Short-Term
Memory
(LSTM)
neural
network.
Both
stepwise
iterative
direct
multi-step
LSTM
achieve
high
predicted
heave
study,
some
extent,
affirms
feasibility
power
industry
provides
useful
scheme
short-term
Journal of Ocean Engineering and Science,
Год журнала:
2024,
Номер
unknown
Опубликована: Июнь 1, 2024
The
twin-barge
float-over
technique,
incorporating
a
dynamic
positioning
(DP)
system,
has
been
increasingly
utilized
to
enhance
the
installation
capacity
and
efficiency
of
offshore
platforms.
But
DP
system
is
not
fully
considered
during
design
stage
at
present.
This
study
investigates
responses
integrating
flexible
connections
system.
A
numerical
model
developed
combined
with
model-scale
experiments
analyze
characteristics
findings
reveal
significant
influence
on
coupled
leading
harsh
oscillations
in
roll
heave
directions.
To
effectively
address
this
oscillation,
method
eigenmodes
analysis
filter
adjusting
proposed.
robustness
verified
through
sensitivity
analysis,
further
investigation
conducted
motion
response
under
varying
environmental
conditions.
proposed
paper
are
also
applicable
various
multi-vessel
cooperative
transportation
scenarios.
