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ATMA 2014
20 YEARS OF RESEARCH
IN HYDRODYNAMIC AND STRUCTURE
AT BUREAU VERITAS
Quentin DERBANNE, Sime MALENICA, Xiao-Bo CHEN,
Louis DIEBOLD
BUREAU VERITAS – Division Marine & Offshore – Neuilly-sur-Seine
RESUME
Les travaux du Département Recherche du Bureau Veritas ont été récompensés par le prix 2013 du
CEMT (Confederation of European Maritime Technology Societies). A cette occasion, ce mémoire
revient sur les innovations principales de ces 20 dernières années dans les domaines de
l’hydrodynamique et de l’hydro-structure. Les logiciels HydroStar et Homer, développés par Bureau
Veritas, ont bénéficié de nombreuses innovations et sont maintenant des références dans leur domaine
largement utilisés de par le monde. Dans le domaine du sloshing, Bureau Veritas a su développer une
expertise de haut niveau grâce à des essais sur maquette indépendants, à l’emploi de la CFD et à des
travaux sur les statistiques des pressions de sloshing. Enfin des travaux importants ont été menés sur
les méthodologies de design, permettant de faire le lien entre l’approche calcul direct et l’approche
réglementaire.
SUMMARY
The Confederation of European Maritime Technology Societies (CEMT) 2013 Award in recognition
of a significant contribution to the European Maritime Industry was made to the Research Department
of the Marine Division of Bureau Veritas for their outstanding research in the field of hydrodynamics
and hydro-structure. This paper gives a quick overview of the past 20 years of innovations in these
fields. HydroStar and Homer software, developed by Bureau Veritas, are based on many innovations,
and are now at the state of the art level and widely used worldwide. Bureau Veritas has developed a
very high level expertise in sloshing, based on independent sloshing model tests, the use of CFD and
research on statistical laws to extrapolate the sloshing pressures. Finally important work has been done
on design methodologies that enables to treat the direct computation approach and the rule approach in
a consistent manner.
1. INTRODUCTION
Annually the CEMT (Confederation of
European Maritime Technology Societies) to
which ATMA is member, grants awards in
recognition of the outstanding contribution
made to the success of the European maritime
industry by an individual, company or
organisation. The 2013 award have been
granted to 4 engineers of the Research
Department of Bureau Veritas, so it appears of
interest to remind, in their main lines, the
studies which have been performed within this
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department since some 20 years ago, in the
domain of competence of the recipients:
hydrodynamic and hydro-structure.
The aim is not to detail all research studies
performed during this period at Bureau Veritas.
We shall remind only that the competences of
this department extend on a large set of
disciplines: hydrodynamic, mooring, hydro-
structure, tests and measurements, sloshing,
ice, structural integrity and risk, safety, energy
and environment, design methodologies, ….
2. HYDRODYNAMIC
Referring hydrodynamic, the most important
Bureau Veritas bringing is surely the
development of the HydroStar software,
seakeeping software which solves the potential
equations of the fluid dynamic around floating
or fixed structures. It is the result of research
studies started in 1984 at the Ecole Centrale de
Nantes during the Xia-Bo Chen Phd thesis,
then continued at the Institut Français du
Pétrole, then at Bureau Veritas since 1991.
HydroStar is now used by all the Bureau
Veritas technical teams, and by external clients
(some fifty licences have been sold all around
the world).
We shall not describe here the software
functions in detail but provide a quick view of
some innovative functionalities which have
been developed by Dr Chen and his team and
which now make HydroStar one of the best
computer code of this type in the world.
2.1. Efficient algorithms
Since its design HydroStar has been thought to
be quick and robust.
The Green function is a very complex
mathematical function, which is the basic brick
used to solve the potential flows. If its
formulation is known since very long time, the
methods to calculate it may be different. The
calculation of the Green function in HydroStar
is based on a separation between a singular
part (Rankine) and a regular part. To save
calculation time, the regular part is
approximated by a series of polynomials, the
coefficients of which have been pre-calculated
and integrated in the computer code.
Figure 1 : Regular parts of the Green function
with infinite depth (upper part) and
complements for limited depth (lower part)
Always in the aim to improve the calculation
time, the used solvers to solve the integral
equations have been optimised, and the
software thought in a modular way.
2.2. Validations and comparisons
Since its design, the HydroStar code results
have been compared to existing analytical
results of simple geometries (half sphere,
cylinder, …) or to model test basin results for
more realistic geometries. Today a testing
procedure has been set up which compares
automatically the results of each new version
with reference results in view to verify the
code non-regression.
The HydroStar code results are also regularly
compared to competing codes. The result is
that HydroStar is a very robust code, as well
for the meshing convergence than for the
irregular frequencies treatment, all with a
calculation speed rather higher than the
average. The differences are more visible for
the second order loads, as illustrated here after.
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Figure 2 : Added masses and added damping
comparison with a half sphere analytical
results
Figure 3 : Test-calculation comparison for a
side by side tanker and FPSO
Figure 4 : Different computer codes drift loads
comparison
2.3. Second order loads
HydroStar presents significant differences with
its competitors by the innovations in the
calculation of the second order loads. The
classical theory considers two methods for the
calculation of these loads.
The near field method is based on a direct
integration of the hull pressures. This method
presents a very low convergence: it requires a
very fine mesh to obtain good results.
The far field method allows to solve this
dependence to the mesh, but its application is
limited to horizontal plane drift loads, and for
only one floater.
An intermediate method, called middle field,
has been introduced in HydroStar. It uses a
control surface which surrounds the floater and
allows to obtain the advantages of the two
previous methods: determination of all
components of the loads, applicability to multi-
floaters simulation, drift loads and low
frequency loads O(), very good
convergence with respect to the mesh.
Figure 5 : Control surface used by the mean
field method
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Figure 6 : Drift loads: mesh influence for the
near and mean field methods
The calculation of the second order low
frequency loads, resulting of the interaction
between two wave components with close
frequencies is very time consuming. An
approximated method, proposed by Newman,
allows a simple calculation of these low
frequency loads from the drift loads (mean
loads). But, this approach is only valid for very
low frequencies. An intermediate approach has
been introduced in HydroStar, based on an
innovative formulation, and it provides much
better results than the Newman approximation,
with a calculation time scarcely greater.
Figure 7 : Comparison of the second order
loads obtained with the complete QTF, the
Newman approximation, and the
approximation O()
2.4. Introduction of dissipation in the
potential flows
The potential theory presents the great
advantage to allow very efficiently solving of
the fluid dynamic equations, taking into
account very precisely the inertial effects
(waves, behaviour on wave, …), but locally it
leads to neglect the dissipation from the
viscous and turbulent origins, and so can lead
to very bad previsions for some pathological
cases.
A possibility offered by HydroStar is to
introduce a damping effect in the potential
equations, not to simulate precisely the viscous
flow, but to globally take into account the
resulting energy dissipation.
A damping area can be created on the free
surface. It is, for example, the case when two
ships side by side are simulated. In this case;
the potential theory has a tendency to over-
estimate the wave height between the two
ships. The introduction of a damping, which is
introduced by HydroStar directly at the level of
the integral equations which include the
dissipation area, allows to obtain a realistic
simulation of this case.
Figure 8 : Test-calculation comparison of the
surface motions between two barges
The other application case is the tank sloshing
simulation. The potential theory predicts, when
the excitation frequency is equal to the tank
free frequency, an infinite liquid motion
associated to infinite loads. Effectively, there is
no damping of potential origin. The
introduction of a numerical dissipation on the
tank walls allows to limit the sloshing to
realistic values, and to allow the calculation of
the ship dynamic coupled with her tanks
(tanker, LNG, FPSO).
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Figure 9 : Ship motion coupled with her tanks
3. HYDRO-STRUCTURE
The developments in the hydro-structure area
started at the beginning of the 2000s. It appears
necessary at that time to be able to link the ship
behaviour on wave performed with HydroStar
with the structural calculations performed with
a finite elements software (Nastran, Abaqus,
…). The exploratory studies, initiated by Sime
Malenica, lead in 2012 to the Homer software.
This software transfers the calculated pressures
by HydroStar to the ship structure mesh, then
collects the stresses and the deformations
calculated by the structural computer code. But
this apparent simplicity hides in fact numerous
more complex details to assure a robust and
efficient link.
3.1. An original solution to transfer the
pressures
The coupling requires a transfer of the
pressures calculated by the hydrodynamic code
to the structure mesh. But in general the
considered mesh to solve the hydrodynamic
problem differs from the mesh used to solve
the structural problem. The more intuitive
method consists to interpolate the pressures of
the hydrodynamic mesh toward the structural
mesh, but this method is not robust as the
interpolation introduces errors, and the loads
obtained by pressure integration on the
structural mesh are then different than the
loads considered in the seakeeping code! The
result is that the model is not correctly
balanced for the finite element calculations.
Figure 10 : Structure and hydrodynamic mesh
of a container ship
Homer uses an original method which comes
from the core of HydroStar using the
properties of the Green function. HydroStar is
only used to solve the flow around the ship.
Then it calculates the pressures directly at the
Gauss points of the structural mesh (no
interpolation). The global loads are then
obtained by pressure integration on the
structural mesh, and the ship motions are
solved by Homer. This method assures a
perfect equilibrium of the finite element
model, whatever are the differences between
the hydrodynamic and structural mesh. Homer
is, as we know, the only hydro-structure
software in the world that applies this method.
3.2. Hydro-elastic calculations
For large size ships it has become necessary to
take into account dynamically the ship girder
main deformations. The method used by
Homer is based on a modal approach. The
method is not new, but it is used here with a
3D approach for the structure. The free modes
of the dry ship are obtained from a modal
analysis of the finite element model. The
deformations are then transferred to the
hydrodynamic model, and the ship motions
and deformations are solved in the same way
than for a rigid body, the only difference being
that there are now N deformation modes
instead of 6.
The coupled elastic hydrodynamic behaviour
solution leads to resonance peaks at the
structural natural frequencies, which can
induce a significant increase of the fatigue
damage of the structural details.
The modal approach has the advantage to
allow to take into account some free mode
resonances of the ship hull girder, but
considers a cut-off of the ship deformation
basis. The direct approach (also called quasi
static) does not take into account the structure
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dynamic, but take into account all degrees of
freedom of the structural model. The approach
used in Homer is hybrid; it combines the two
previous approaches: the response is split
between a quasi static response and a dynamic
response. The quasi static response is
calculated by a direct approach and the
dynamic response by the modal approach. The
so obtained total response combines the
advantages of the two previous methods.
Figure 11 : Free mode of a container ship and
application of the deformation to the
hydrodynamic mesh
Figure 12 : Transfer function of a hatch corner
stress
3.3. Whipping simulation
The large container ships are subject to
whipping, transient vibration induced by the
wave impacts on the ship bow, with a possible
significant increase of the stresses in the ship
structure. The hydro-elastic model previously
presented can be used to simulate this
phenomenon. To do so a simplified model for
the impact loads is introduced, and the ship
motions are solved in time domain, taking into
account the hydrostatic deformations and
incident wave non linear loads. Studies are
always under progress to improve the impact
load prediction.
Figure 13 : Midship section bending moment
with whipping
3.4. A very general software
Homer, even if it has been developed to
answer to an urgent need of hydroelastic
simulations of container ships, can be applied
for any kind of ship or offshore structures, and
for any type of simulation (quasi static,
springing, whipping, multi-bodies).
Figure 14 : Homer simulations of different
units
4. SLOSHING
The sloshing phenomenon in LNG carriers
corresponds to the LNG motion induced by the
ship motions during navigation or at fixed
point. The sloshing is a multi scale
phenomenon highly non-linear and can be
violent, i.e., can induce damages in LNG,
FLNG or FSRU tanks. Since the 2000s,
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research studies have been performed at
Bureau Veritas by Mirela Zalar and Louis
Diebold, based on the experimental and
numerical approaches.
4.1. CFD calculations
The target of the CFD (Computational Fluid
Dynamics) is to evaluate the flow cinematic
and the loads applied to the structure which
lays behind the insulation system. The Flow3D
code, used at the beginning has been
substituted by the OpenFOAM code which is a
parallel CFD code and an "open source" which
can simulate complex flows (large scale
simulations, RANSE model, compressible
flows…). This calculation tool has been
validated by numerous comparisons with test
results.
Within the scope of the European project
Marstruct, a series of tests have been
performed in a quasi 2D tank. The agreement
between tests and OpenFOAM (CFD
calculations) are excellent for the free surface
elevation, the applied moment by the fluid on
the tank walls and for the pressure as
illustrated on figure 15.
-5
0
5
10
15
20
25
0 5 10 15 20
Pre
ssure
at sensor N
°3
Time (s)
Case B - T=T0 - Sensor N°6
Comparison Experiments / Numerics
Num.
Exp.
-4
-2
0
2
4
10 11 12 13 14 15 16
Glo
bal T
orqu
e
Time (s)
Case A - T=T0 - Global Torque
Comparison Experiments / Numerics
Exp.
Num.
Figure 15 : Comparison between tests and CFD
calculations of the surface elevation, pressure and
global moment induced by the fluid on the tank
Within the scope of a cooperation with Ecole
Centrale de Nantes, BV performs its own
sloshing test programs. Numerous filling
configurations, motion amplitudes and
frequencies have been tested. The comparisons
between the measured loads and the loads
calculated by Flow3D and OpenFOAM are
presented on figure 16.
-100
-50
0
50
100
22 23 24 25 26 27 28 29 30
Fy(N
)
Time (s)
comparison -Flow3d-OpenFoam-EXP- test586
Amplitude=1m
Frequency=0.854
OpenFoam 1m Fy
Flow3D 1m Fy
EXP essai 586 Fy
Figure 16 : Comparison of the global loads
given by tests and CFD calculations (Flow3D
& OpenFOAM) – 20%H – 1m – f=0.854Hz.
The computers today allow to perform long
simulations of several hours for irregular sea
states, to extract the statistics of the loads and
to compare them to the measured loads during
tests. Here also the statistical comparison is
very good.
Figure 17 : Comparison of the global loads on
irregular waves and convergence with different
meshes (simulation of 3 hours)
4.2. Dynamic gauges
An innovation of Bureau Veritas in CFD
calculations has been the development of a
dynamic gauges module.
In principle, the CFD calculations providing all
data at each time step and in all mesh can
provide a complete representation of the
sloshing impacts on the tank walls.
Unfortunately the CFD studies must be only
concentrated on predefined areas (as for the
sloshing test on small scale model) as the
storage of all the data at each time step
requires too much place on a storage disc.
To solve this problem a specific post-treatment
called "Dynamic gauge" has been developed at
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Bureau Veritas. At each time step, the flow is
analysed and the eventual sloshing impacts are
detected and recorded when the pressure or the
velocity normal to wall flow exceeds a
threshold fixed by the user level. When an
impact is detected (pressure or normal velocity
exceeding the threshold) a "dynamic gauge" is
created at the impact point. Each impact is then
recorded within a time window also fixed by
the user for a later verification. Finally this
specific post-treatment tool allows to obtain a
complete knowledge of all sloshing impacts on
the tank walls and that during all the
simulation time.
The following figure 18 represents all sloshing
impacts detected on the tank top during a
simulation of a real sea state (i.e. irregular
motions and simulation corresponding to a
duration of 5 hours).
Figure 18 : Map of impacts on the tank top for
a sea state simulation during 5 hours at real
scale with OpenFOAM
4.3. Independent tests
Thanks to a cooperation with Ecole Centrale
de Nantes and to GTT which provided a tank
model, Bureau Veritas has been able to have
its own tests in view to obtain its own expertise
leading to the writing of the guidance note
NI554 which describes the method to evaluate
the sloshing loads and the tank wall scantlings.
In particular this note indicates the tests to be
performed, the pressure gauges to be used, the
sampling frequencies, the identification of the
pressure peaks, the type of statistical post-
treatment …
Figure 19 : Sloshing test on hexapod
4.4. Sloshing statistics
The applied approach for the LNG tank design
was based at the beginning of the 2000s on a
called short term approach, using only the 3h
pressures obtained on some design sea states.
The method is now a long term method taking
into account all sea states encountered by the
ship. This method requires the extrapolation of
the test results on durations much longer than
the test durations.
The Weibull distribution is generally applied
by industry as statistical adjustment for
pressure samples. In view to determine if this
Weibull law is the best adapted adjustment law
for peak pressures, Bureau Veritas performed a
specific test campaign to obtain a sample of
480 hours (96 tests of 5 hours), instead of the
maximum 30 hours generally considered, and
adjusted the pressure samples using different
techniques: Weibull law, Pareto or GEV law,
POT method, Maxima Block method. The
studies have shown that the Weibull law leads
systematically to underestimate the extreme
pressures. On the opposite, the Pareto law, or
the Maxima Block method allow a better
statistical evaluation of the extreme pressures.
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Figure 20 : Extrapolation of a 5h duration test
with a Weibull and a Pareto law
Figure 21 : Sloshing test of 480h duration
5. DESIGN METHODOLOGIES
All these direct calculation software which
allow to precisely simulate the hydrodynamic
and structural response of a ship under a given
sea state are of no use if they are not associated
with a design methodology. The target of a
direct calculation procedure, or a rule
approach, is to provide the scantling of a ship
or offshore structure versus the environmental
and operational conditions which will be
encountered. It is necessary to evaluate, on the
whole life time of the unit, the extreme
responses in terms of stresses, deformations or
motions, and the fatigue damage.
The rule procedures are more and more
substituted, or complemented, by direct
approaches, based on deterministic
calculations (for example whipping
calculation) or by tests (sloshing tests). To
assure the consistency between these two
approaches, it is necessary that both are based
on the same hypothesis in terms of
environmental and operational conditions. It
will be therefore even possible to use direct
calculations to validate or modify rules.
5.1. Direct calculation methodology
There is a great number of types of
deterministic simulation models (HydroStar,
Homer, CFD, ….) from the simplest and less
calculation time consuming models till the
more precise and more time consuming ones.
All are unfortunately not able to simulate the
total life of a structure (25 years for a ship;
more than 50 years for an offshore structure).
It is therefore necessary to be able to simplify
the encountered sea state statistics to be able to
have shorter simulations.
The most complete description is given by a
statistic of the sea states classed versus
significant height and peak period. These
tables are used for a long term approach which
consists to simulate all the life time of the unit.
The use of this approach is limited to very
simplified deterministic simulations (linear
approach for example).
0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 1
0 0 0 0 0 0 0 0 0 0 0 0 1
0 0 0 1 1 1 0 0 0 0 0 0 3
0 0 0 1 2 2 1 0 0 0 0 0 0 6
0 0 1 3 4 3 2 1 0 0 0 0 0 13
0 1 3 6 7 5 3 1 0 0 0 0 0 26
0 0 2 7 13 13 8 4 1 0 0 0 0 0 48
0 1 5 16 24 20 11 5 2 0 0 0 0 0 83
0 2 14 33 39 27 13 5 1 0 0 0 0 133
0 0 7 32 57 51 28 11 3 1 0 0 0 0 191
0 2 22 62 74 49 21 6 2 0 0 0 0 238
0 10 50 77 56 24 7 2 0 0 0 0 226
0 1 9 12 6 2 0 0 0 0 31
1-2 2-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10 10-11 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19 Total
0 0 0 2 21 93 199 249 209 129 62 25 8 2 1 0 0 0 1 000
< 1
�
Up-crossing period Tz
Total
4 - 5
3 - 4
2 - 3
1 - 2
8 - 9
7 - 8
6 - 7
5 - 6
Sig
nif
ican
t w
ave
he
igh
t (m
)
> 16
15 - 16
14 - 15
13 - 14
12 - 13
11 - 12
10 - 11
9 - 10
Figure 22 : IACS sea states table
With certain hypothesis it is possible to reduce
the sea states table to only some design sea
states for which the extreme responses will be
determined: This is the short term approach.
It is sometime necessary to simplify even more
the sea state description to consider only one
wave, or one group of waves: It is then the
design wave approach.
Evidently, each time that we simplify the
environmental description, accuracy is lost for
the sea state representation, but is gained for
the ship response simulation with the used of a
more precise simulation software.
The optimal design approach is the approach
which will combine these different approaches
to step by step reduce the simulation
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conditions and increase the complexity of the
simulations.
-15
-10
-5
0
5
10
15
-50 -25 0 25 50Time (s)
Wave
Figure 23 : Irregular design wave
The extreme simplification of the sea
conditions consists to delete the hydrodynamic
calculations and to apply formulas which
provide directly the loads to be applied to the
structure. It is the approach selected for the
classification society rules. These require to
verify the structure with a limited number of
loading cases, indicating each time the load to
be applied. These loading cases are in fact a
rule simplification of the design waves which
are finally a simplification of some 70 000 sea
states that the ship will see during her life.
5.2. Direct calculation and rules
development
When the consistency is found between the
direct calculation and the rules approach, it is
possible to use the calculation for the rules
evolution.
A first example has been, within the IACS, to
harmonize the tanker and bulk carrier rules.
Bureau Veritas was in charge of a working
group dealing with the scantling loads. At this
occasion the application of the design waves
has been generalised, and all the loading
combination coefficients as well as the sea
pressure have been calibrated applying this
approach. The application of the design wave
approach has also been applied to justify the
selection of a limited number of the rule
loading cases, for fatigue and for extreme
responses.
In addition, a refine analysis of the
contribution of the stress cycles to the
cumulative fatigue has shown, because more
robust, that it is better to define the rule loads
for fatigue with a probability level of 10-2
(there were before defined at 10-4
). This
approach, duly justified by calculations, is a
major modification in the fatigue rule
approach, and a lot of pedagogy and patience
have been necessary to convince our IACS
partners.
N25
s ref
P ref * N25
0
50
100
150
200
250
300
1E+00 1E+02 1E+04 1E+06 1E+08
Cumulative number of cycles
Str
ess
ran
ge s
x = 1.15
x = 0.8
10-6
10-4
10-2
1
Probability
Figure 24 : Weibull law distribution shape
parameter influence on the fatigue life time
Other works in progress within IACS planned
to be finalized at the end of 2014, aim to
redefine the rule vertical wave bending
moment formula, using direct calculation
results. The calculations effectively allow to
identify the different components of the rule
formula: wave parameter, non dimensional
part, non linearity coefficient. The results show
that the difference between the current formula
and the calculation are more important for
containerships that for tankers or bulk carriers.
The new formula, which are always under
discussion, aim to decrease this difference.
0.50
0.70
0.90
1.10
1.30
1.50
1.70
1.90
0.7 0.8 0.8 0.9 0.9 1.0 1.0
Cb / Cw
Lin
ear
VB
M / R
ule
valu
e
Bulk Carriers Oil Tankers
Containerships General Cargo
LNG Carrier Passengerships & Ro-Ro
Figure 25 : Comparison between the rule
vertical bending moment and the calculated
moment by a direct approach
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6. CONCLUSION
The Research and Development works allow
Bureau Veritas to develop its own tools and
methods at the upper level of the State of the
Art in view to acquire an independent expertise
to develop its classification rules, answer to the
client questions, and act within IACS and the
maritime and offshore scientific community.
Research and Development is based on a
continuous questioning in view to maintain a
newer as possible eye on the problems which
we have to face.
Within the future research axis in Bureau
Veritas, the CFD is called to be extended. The
CFD, which is used since some ten years to
solve the ship resistance and ship hull
optimisation has now reached a sufficient
maturity to begin to be used for ship behaviour
on waves, which requires to be able to simulate
irregular sea state during long time. It will
allow so, to more precisely answer to the
slamming, green water on deck, ship behaviour
on extreme waves, wave added resistance,
local and violent flows problems. The aim for
the coming years is to develop CFD tools and
to include them in the global methodological
approach which will have to efficiently apply
the linear, non linear potential codes, and the
CFD to obtain the more complete and precise
design procedure.
Another important research axis deals with the
dynamic simulation of one or various offshore
structures coupled with their mooring lines,
risers, including the effects of current, wind,
the second order loads, the wave non linearity,
the large motion amplitudes.
Finally, the rule development is always at the
working agenda to allow to propose rules each
time more precise, but also easier to be
understood, and more coherent with the direct
approaches.
7. REFERENCES
7.1. Hydrodynamic
[1] Evaluation de la fonction de Green du
problème de diffraction/radiation en
profondeur d’eau finie, 4èmes Journées
de l’Hydrodynamique, 1993
[2] On the Irregular Frequencies Appearing
in Wave Diffraction-Radiation
Solutions, S. Malenica and X.B. Chen,
Int. J. of Offshore and Polar Eng., 1998,
vol.8, no.2
[3] Hydrodynamics in Offshore and Naval
Applications, Chen X-B., 6th
International Conference on
Hydrodynamics, Perth, Australia, 2004
[4] Middle-field formulation for the
computation of wave-drift loads, J. Eng.
Math., 2007, vol.59
[5] Second-Order Wave Loads on a LNG
Carrier in Multi-Directional Waves, M.
Renaud, F. Rezende, O. Waals, X.B.
Chen and R. van Dijk, OMAE, 2008
[6] First and Second Order Wave-Current
Interactions for Floating Bodies, C.
Monroy, Y. Giorgiutti and X.B. Chen,
OMAE, 2012
[7] Hydrodynamic issues of FLNG systems,
X.B. Chen, L. Diebold and G. de
Hauteclocque, OMAE, 2013
[8] A Practical O() Approximation of
Low Frequency Wave Loads, C.
Monroy, G. de Hautecloque and X.B.
Chen, OMAE, 2013
7.2. Hydro-structure
[9] Hydroelastic response of a barge to
impulsive and non-impulsive wave
loads, Malenica S., Molin B., Remy F.
& Senjanovic I., 3rd Int. Conf. On
Hydroelasticity, 2003
[10] Hydro structure interactions in
seakeeping, Malenica S., International
Workshop on Coupled Methods in
Numerical Dynamics, 2007
[11] Consistent hydro-structure interface for
evaluation of global structural responses
in linear seakeeping, Malenica S.,
Stumpf E., Sireta F.X. & Chen X.B,
OMAE 2008
[12] 3DFEM – 3DBEM model for springing
and whipping analyses of ships,
Malenica S. & Tuitman J., RINA Conf.
on Design and Operation of Container
Vessels, 2008
[13] Fully coupled seakeeping, slamming and
whipping calculations, Tuitman J.T. &
Malenica S, Journal of Engineering for
Maritime Environment Vol. 223, No
M3, 2009
Tous droits de reproduction réservés – ATMA 2014
[14] Consistent hydro structure interface for
partial structural model, Sireta F.X.,
Malenica S., Chen X.B. & Marchal N,
Deep water Offshore Specialty
Symposium, 2009
[15] Transfer of non-linear seakeeping loads
to FEM model using quasi static
approach, Tuitman J.T., Sireta F.X.,
Malenica S. & Bosman T.N, ISOPE
2009
[16] Local hydro-structure interactions due to
slamming, Malenica S., Sireta F.X.,
Tomasevic S., Tuitman J.T. &
Schipperen I., MARSTRUCT 2009
[17] Validation of the global hydroelastic
model for springing & whipping of
ships, Derbanne Q., Malenica S.,
Tuitman J.T., Bigot F. & Chen X.B,
PRADS 2010
[18] Discussion on hydroelastic contribution
to fatigue damage of containerships, Q.
Derbanne, F.X. Sireta, F. Bigot and G.
de Hauteclocque, 6th Int. Conf. On
Hydroelasticity, 2012
[19] Global Hydroelastic Ship Response:
Comparison of numerical model and
WILS model tests, F. Bigot, Q.
Derbanne, F.X.Sireta, S. Malenica,
ISOPE 2011
[20] Hydroelastic response of a ship
structural detail to seakeeping loads
using a top-down scheme, FX Sireta, Q.
Derbanne, F. Bigot, S. Malenica and E.
Baudin, OMAE 2012
7.3. Sloshing
[21] Dynamic coupling of seakeeping and
sloshing, S. Malenica, M. Zalar & X.B.
Chen, ISOPE 2003
[22] Sloshing effects accounting for dynamic
coupling between vessel and tank liquid
motion, M. Zalar, L. Diebold, E. Baudin,
J. Henry and X.B. Chen, OMAE 2007
[23] Design Sloshing Loads for LNG
Membrane Tanks, NI554 DT R00 E,
Guidance Note, May 2011
[24] Statistical Post-Processing of a Long
Duration Test, B. Fillon, L. Diebold, J.
Henry, Q. Derbanne, E. Baudin and G.
Parmentier, ISOPE 2011
[25] Experimental and Numerical
Investigations of Internal Global Forces
for Violent Irregular Excitations in
LNGC Prismatic Tanks, L. Diebold, N.
Moirod, E. Baudin and T. Gazzola,
ISOPE 2011
[26] Détermination des Chargements dus au
Sloshing. Application aux unités
flottantes d’opération et de liquéfaction
de gaz (FLNG, FSRU), L. Diebold, N.
Moirod, T. Gazzola and E. Baudin,
ATMA 2012
[27] Dynamic Probes: an on-the-fly CFD
Plug-in for Sloshing Impact Assessment,
T. Gazzola and L. Diebold, ISOPE 2013
[28] Bureau Veritas Sloshing Model Tests &
CFD Calculations within ISOPE
Benchmark, E. Baudin, L. Diebold, B.
Pettinotti, J.M. Rousset and M. Weber,
ISOPE 2013
[29] Extreme Values Theory Applied to
Sloshing Pressure Peaks, B. Fillon, J.
Henry, L. Diebold and Q. Derbanne,
ISOPE 2013
[30] Statistical Behaviour of Global and
Local Sloshing Key Parameters, L.
Diebold, Q. Derbanne and T. Gazzola,
ISOPE 2013
7.4. Long term methodologies
[31] Long-term non-linear bending moment
prediction, Q. Derbanne, J.F. Leguen, T.
Dupau, E. Hamel, OMAE 2008
[32] Evaluation of Rule-Based Fatigue
Design Loads Associated at a New
Probability Level, Q. Derbanne, F.
Rezende, G. de Hautecloque and X.B.
Chen, ISOPE 2011
[33] Comparison of Design Wave Approach
and Short Term Approach with
Increased Wave Height in the
Evaluation of Whipping Induced
Bending Moment, Derbanne Q., Bigot F.
and de Hauteclocque G, OMAE 2012
[34] Comparison of different equivalent
design waves with spectral analysis, G.
de Hauteclocque, Q. Derbanne and A.
El-Gharbaoui, OMAE 2012
Tous droits de reproduction réservés – ATMA 2014
[35] Non Linearity of Extreme Vertical
Bending Moment: Comparison of
Design Wave Approaches and Short
Term Approaches, Q. Derbanne; G. de
Hauteclocque and T. Mienhaou, OMAE
2013
[36] Non Linearity of Extreme Vertical
Bending Moment: Discussion on the
Existing Rule Formulation, Q.
Derbanne, G. de Hauteclocque and T.
Mienhaou, OMAE 2013
[37] Design Wave Selection for Strength
Assessment of Floating Structures, Q.
Derbanne, G. de Hauteclocque, A. El-
Gharbaoui, P. de Belizal, PRADS 2013