A
three-dimensional design code was developed to simulate
the corrosion process and cathodic protection systems
for offshore oil and gas platforms. The software
was developed as part of a project with Conoco Norway,
Corrocean AG and FEGS Ltd.
It is extremely expensive to correct
the effects of an ineffective cathodic protection
system, and there is strong motivation towards numerical
analysis to simulate these systems before the structure
is commissioned. CM developed the numerical simulation
software for the project. The software is known internationally
as BEASY CP and SEACORR/CP. Special tubular elements
were developed for this application to provide a
global analysis of the structure.
Corrosion in offshore structures
occurs by galvanic processes which take place because
the electrochemical properties of different materials
are different. This sets up an electrical current
between the materials and the anode degrades. Although
equations or electrostatics are linear within the
electrolyte (seawater), the boundary conditions are
typically non-linear and time dependent. Current
density and voltage are related by the polarisation
curve, a nonlinear function which can consider temperature,
salinity, oxygen content, and electrolyte flow velocity.
Another important factor is the buildup of calcareous
scale (organic films and marine growths) on the structure
surface.
The software is now available as
a commercial package and allows the corrosion engineer
to evaluate design options, look at problem areas,
interpret experimental observations, optimise the
design and predict with accuracy and confidence the
degree of protection and life expectancy of a cathodic
protection system.
A three-dimensional design code
based was developed to simulate the corrosion process
and cathodic protection systems for offshore oil
and gas platforms. The software was developed as
part of a project with Conoco Norway, Corrocean AG
and FEGS Ltd.
It is extremely expensive to correct
the effects of an ineffective cathodic protection
system, and there is strong motivation towards numerical
analysis to simulate these systems before the structure
is commissioned.
CM developed the numerical simulation
software for the project. The software is known internationally
as BEASY CP and SEACORR/CP.
 Special tubular elements were
developed for this application to provide a global
analysis of the structure.
Corrosion in offshore structures
occurs by galvanic processes which occur because
the electrochemical properties of different materials
are different. This sets up an electrical current
between the materials (anode degrades).
Although equations or electrostatics
are linear within the electrolyte (seawater) the
boundary conditions are typically non-linear and
time dependent. Current density and voltage are related
by the polarisation curve. Nonlinear function which
can consider temperature, salinity, oxygen content,
and velocity. Another important factor is the buildup
of calcareous scale (or organic films and marine
growths) on the structure surface.
The software is now available as
a commercial package and allows the corrosion engineer
to evaluate design options, look at problem areas,
interpret experimental observations, optimise the
design and predict with accuracy and confidence the
degree of protection and life expectancy of a cathodic
protection system.
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