Computational Modeling of CP Penetration and Corrosion Risk in Subsea Crevice Geometries

Abstract Crevices formed in subsea assemblies such as flange interfaces, bolted joints, and tube-to-tube connections, especially those involving bare steel, pose a significant challenge to corrosion control. Depending on geometrical conditions, these confined zones often restrict electrolyte flow and oxygen diffusion, and increase pH towards the deep end, creating conditions where cathodic protection (CP) may not fully penetrate. Predicting the extent of CP penetration into such crevices is essential for ensuring long-term integrity of submerged assets, especially in chloride-rich seawater. This paper describes a deterministic model simulation for CP penetration inside a crevice in a subsea assembly, and presents results obtained in commonly occurring scenarios of crevices occurring in marine offshore environments. The model considers geometrical and physical parameters such as oxygen, and CP potential levels to evaluate their impact on corrosion rates and corrosion risk inside the crevice.