Numerical Study of Bending Behavior for 66 kV Submarine Cables

Abstract

Submarine cables operate in complex marine environments and are repeatedly subjected to lateral loads from ocean currents, waves, and seabed irregularities. As these factors often create free spans that undergo substantial bending deformation, understanding the bending behavior of submarine cables is critical for ensuring their structural integrity. In this study, the bending behavior of a 66 kV submarine cable was investigated using a numerical approach, with particular emphasis on a novel modeling methodology that incorporates various conductor wire configurations. The numerical model was validated against experimentally obtained bending moment values through three-point bending tests, thereby ensuring an accurate representation of the structural response of the cable. As a result, the distribution of von Mises stress decreased by up to 27.3% as the cross-sectional area of the conductor wire increased under identical deflection. The single-conductor wire exhibited a bending moment approximately 132.3% higher than that of the 19-conductor wire. These findings indicate that assuming a conductor wire with a fully solid cross-section may lead to overestimation. This underscores the importance of determining the optimal number of conductor wires in 66 kV submarine cables, for which the proposed numerical modeling approach can be adopted.