Three-dimensional modeling of in-ground cathodic protection systems with deforming anodes

Abstract

The design of sacrificial cathodic protection (CP) systems conventionally involves steady-state assumptions, which means design parameters are considered constant during the in-service life of CP systems. In contrast, it is evident by experimental observations (including field measurements) that cathodic protection is a transient process due to variations in electrolyte properties such as seasonal changes in electrical conductivity of soil, depletion of anodes, and formation of corrosion deposits on anode material surface, to name a few. The lack of practical time-dependent models on this critical issue is apparent in the literature; accordingly, in this study, a pseudo transient electrochemical model is adopted to highlight the transient behavior of cathodic protection systems and investigate key differences with steady-state behavior. For the sake of demonstration, the developed model is used to simulate the time-dependent performance of a sacrificial anode bed for cathodic protection of screw-pile foundations. The methodology proposed in this study can be used by corrosion engineers to improve and optimize the design of CP systems and numerically estimate the performance of sacrificial anodes and the level of protection over time.

Corrosion deposition in deforming anodes of in-ground cathodic protection systems: A three-dimensional transient study

“…In previous works and using 3D simulations, the design of the anode bed and the selection of the optimal mode in the steady-state were investigated 27,28 and in another work, with the development of simulation factors, the process of protecting the structure over 30 years with anode deformation was studied. 29 In the end, by using wire anodes with backfill and ribbon mesh, the cathodic protection process of the tank bottom was investigated and economic aspects and key parameters were examined. 30 This paper is organized as follows: in the first section, after presenting the considered geometry and expressing the problem hypotheses, the relations governing the simulation model are described i.e.…”

Numerical Analysis and Design Recommendation for Linear Anodes in above Ground Storage Tank Cathodic Protection Systems: Mesh Grid system vs. Concentric Rings

“…Furthermore, a thorough study of wire anodes has been lacking in previous studies. In previous works, we investigated the 3D simulation of anode beds from the perspective of design and optimization under steady-state conditions [10,11] and considered the transient nature of the corrosion process with deforming anodes for cathodic protection of irregular geometries [12].…”