Comparative analysis on mechanical behavior according to Armor-types of dynamic cable: A FEM-based design perspective

This study compares round-wire armour (RW) and flat-wire armour (FW) concepts for a 70 kV-class dynamic inter-array cable based on a DNV-verified baseline design; to clarify how armour-wire cross-sectional geometry affects mechanical response and fatigue behavior. To isolate geometry effects, both configurations were designed with equivalent armour-layer crosssectional area and analyzed under identical loading conditions using a commercially available finite element tool that accounts for contact–friction interaction and nonlinear stick–slip behavior. The FW concept enables a more compact cable and generally shows favorable trends in global mechanical performance, including axial and torsional stiffness/response and resistance to hydrostatic-pressure-induced radial deformation. These characteristics indicate strong potential for deep-water, tension-dominated applications where stable system-level behavior is critical. In bending, FW improves global flexibility; however, edge-related stress concentration and altered stick–slip response increase local stress levels, resulting in less favorable bending-fatigue performance for the idealized sharp-edge profile considered. Further work should refine the flat-wire cross-section, including edge fillets and aspect-ratio optimization, and validate the predictions through testing to confirm practical applicability.