Author(s)

A. Peratta

Abstract

This paper presents a hybrid two dimensional Dual Reciprocity Boundary Element Method (DRBEM) for modelling the primary reactions of iron corrosion in an acidic solution. The main focus is on the establishment of the DRBEM approach for this kind of problems in which the mathematical formulation is based on the Planck-Nerst law, the conservation of charge and the conservation of mass for the species participating in the process. The model is capable to describe the transport process of Fe+2 and H+ ions in the aqueous electrolyte driven by the instantaneous electric field that results from the existent charge distribution. The results of this work compare qualitatively well with previously established references. 1 Introduction Numerical modelling of corrosion cells is necessary in order to understand the basic principles involved in the process. Even the simplest system with primary chemical reactions can represent a challenging problem from both the theoretical and numerical points of view. The high complexity of the phenomenon is mainly due to the non-linear coupling between the transport and electric field equations in the electrolyte, and more specifically in the region close to the anodic and cathodic nests. The understanding of the basic principles may lead to novel techniques for corrosion control, and may help to avoid expensive experimental setups. The goal of this work is to establish a Dual Reciprocity Boundary Element Method (DRBEM) for solving iron corrosion problems in which the anodic and cathodic surfaces are well identified in advance. The conceptual model discussed in this work is sketched in Fig. 1. In particular, this paper focuses in the primary reactions occurring in the anode and cathode, and defers the secondary reactions (i.e. rust formation) for

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