Initial results of pipeline modelling in Great Britain

Large geomagnetic field variations during geomagnetic storms induce telluric currents in pipelines. These currents can lead to variations in the pipe-to-soil potentials (PSPs) which interfere with corrosion-prevention measures and may enhance corrosion, leading to localised damage and a reduced lifetime of the pipeline. Modelling PSP fluctuations is useful for mitigation measures in existing pipelines, as well as at the design stage to allow new pipelines to be built to withstand such impacts. We present a first attempt to build capability for modelling these currents in the high-pressure gas pipeline network of the United Kingdom. Our philosophy is similar to the approach used in the modelling of the UK high-voltage (HV) electrical network, as the pipeline network topology is somewhat similar to that of the HV network across much of Britain. We use the method of Boteler (GJI, 2013, doi: 10.1093/gji/ggs113) and modify our existing HV code to account for the continuous grounding of the pipelines, splitting each pipeline into straight-line segments and assuming a constant surface electric field within each section. We present some early results for simple pipeline models and simplified electric fields and we discuss the results.