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Dimensions of vessel
and mooring lines in Vessel Lines Screen
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Dimensions of berth
and ship mooring points in Berth Screen.
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Mooring arrangement in
Mooring Screen with extra features drag-and-drop in
graphical interface.
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Wind, current and
tides in General Environment Screen.
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Special circumstances
such as a tug boat, ice bergs, a passing vessel and wind
gusts.
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Catenary effects
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Different types of
wire: steel, kevlar, nylon, polyester, polypropylene,
chain, dynamax, VETS.
Any type of vessel that is
moored alongside a pier, a sea island or at any offshore
ship mooring.
There is a normal and a dynamic version available. Special
feature of the dynamic verison are vessel movement after
sudden mooring-line failure, wind gusts, sudden change in
current after turn in tide, a passing vessel, static
thruster requirements for a DP Ship.
In
addition the dynamic version can be used for all types of
single moorings and turrets because of their freedom of
movement and relatively long natural periods. Free drifting
can also be modelled, taking into account wind, waves,
current and tug boats.
Users:
U.S. Clients and Projects
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Allied Signal
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Conoco, Inc
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Du Pont
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Exxon Oil Corporation
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Mobil Corporation
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Shell Oil Company
(Riser Protection Net)
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U.S. Navy
International Clients and
Projects
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AMEC Offshore
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Aramco
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British Petroleum
Company
British Telecommunications
Documentation:
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Ongoing research and development for future program
releases
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Clear and easy to
reference manuals.
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Hotline telephone, fax
and e-mail support by experienced engineers.
Postprocessor output:
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Mooring line and
fender loads, vessel movements and change in freeboard.
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Local current and
tidal current forces and moments, wind forces and
moments in Environment Screen.
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Heaviest wind load
from least favourable direction, plotted in “Wind Force
Rose”
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Change in mooring
loads over time.
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Line tending feature to show how to alleviate the burden
on overloaded mooring-lines
Solution:
Normal analysis is
quasi-static. Disequilibrium-force, which is defined as the
difference between external forces and mooring-line reaction
forces, is calculated for assumed position. Position is
changed by iteration until satisfactory equilibrium is
reached.
When equilibrium is not
reached within 1000 iterations, the message “Inadequate
Mooring” appears, which can be due to physical problems.
In the dynamic analysis
short-term behaviour is dominated by forces that change over
a time-scale of seconds and minutes. Forces that change
slower than than the natural periods of mooring-oscillations
have little dynamic effect and can be calculated accurately
enough and much easier through the quasi-static method.
The dynamic
disequilibrium-force is calculated in the same way as for
the quasi-static situation. However, instead of convergence
to an equilibrium, accelerations are calculated. Velocity
and position of the vessel are calculated through
integration over time over time intervals of 0.1 second. All
forces are assumed to be constant in this interval. At each
new time-interval, all forces are recalculated.
Results are presented graphically and can be edited in the
“plot-window”.
Modelling:
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Quasi-static and
dynamic analysis of mooring lines and fender loads,
vessel movements and change in freeboard.
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Special circumstances such as DP-thrusters, winches,
ice, tug boats, wind gusts, change in mooring loads over
time and low frequency motions.
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No
different soil types, no animations possible and no
hydrodynamic interaction between floating bodies
Summary:
OPTIMOOR is a mooring-analysis program based on OCIMF
recommendations and procedures. There is a version for
vessels alongside a pier near the shore and in addition one
for offshore areas. It is possible to simulate quasi-static
as well as dynamic situations. The program is meant to plan
and analyse a vessel’s mooring arrangement and to train the
crew how to handle the moorings and how to react to in
different situations.

Wind
Force Rose
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