Application of the coupled BEM/FEM method for calculation of cathodic protection system parameters
Cathodic protection (CP) is a technique that prevents corrosion of underground metallic structures. Design of any CP system first requires defining the protection of current density and potential distribution, which should meet the given criterion. It also needs to provide, as uniform as possible, current density distribution on the protected object surface. Determination of current density and potential distribution of CP system is based on solving the Laplace partial differential equation. Mathematical model, along with the Laplace equation, is represented by two additional equations that define boundary conditions. These two equations are non-linear and they represent the polarization curves that define the relationship between current density and potential on electrode surfaces. Nowadays, the only reliable way to determine current density and potential distribution is by applying numerical techniques. This paper presents efficient numerical techniques for the calculation of current density and potential distribution of CP system based on the coupled boundary element method (BEM) and finite element method (FEM).