It has been shown in the analysis that there exist complex interactions between multiple adjacent pipelines, pipelines with changing coating properties or with coating holidays and pipelines with independent CP systems that are subject to stray current interference. These interactions cannot successfully be described by design equations and numerical simulation is required if accurate predictions are to be made.
The approach described here, using the Boundary Element Method software BEASY, provides a computationally efficient method to predict the performance of CP systems and assess the impact of electrical interference. The models are useful not only for the design of new CP systems, but also for the analysis of systems that are undergoing modifications or additions of components.
Using computer modelling it is possible to model CP interference in a manner, which is enlightening regarding the processes at work. It can provide information about the level of interference in terms of a parameter (i.e. current density) that more clearly defines the severity of the effect. Furthermore, it can provide important insight into the factors that influence the magnitude of the effect. This makes BEM a useful tool for the design of CP systems.
On the object of stray current corrosion see also: DC traction, Cathodic protection, Coating, Contour plots, Definition, Detection, Examples, External currents, Historical perspective, Impressed current, Interference, Mechanisms, Modeling. Pipeline, Potential distribution, Prevention, Stray fields and leakage, Transit systems
Computer Simulation as an aid to CP System Design and Interference Predictions, Robert Adey and John Baynham, BEASY