Fretting wear and fatigue in submarine power cable conductors for floating offshore wind energy

Multi-strand, copper conductors in submarine power cables (SPCs) for offshore wind are susceptible to fretting wear and fatigue, due to multiplicity and complexity of contacts, subjected to potentially severe dynamic loading. This paper presents (i) a global-local methodology for coupled hydro-aero-elastic dynamic loading of a representative SPC for identification of local inter-wire fretting-related conditions, (ii) fretting wear characterisation of copper conductor material, and (iii) local fretting multiaxial wear-fatigue finite element models for fretting fatigue life assessment of SPC copper conductor contacts. Predicted fretting fatigue lives are shown to be consistent with previously published bending fatigue test data on SPC copper conductors. Fretting fatigue life is shown to be significantly affected by aero-hydrodynamic loading, wear, slip regime and wire diameter.