Optimum Design of Cathodic Protection System by 3-D BEM

Abstract

A three dimensional boundary element method is developed for optimizing the locations and impressed currents of electrodes in a cathodic protection system. The electrodes are regarded as the sources of current, and the potential in the electrolyte is described by the Poisson’s equation with appropriate boundary conditions, in which the polarization of the metal to be protected is taken into account. The Poisson’s equation is solved by the boundary element method, and the optimization is performed by minimizing the power necessary to keep the potential on the metal surface below a critical value. An effective method is proposed for obtaining the derivatives of potential, which are needed in the optimizing procedures. In order to demonstrate the usefulness of the method, some example problems are presented.