This example models cathodic protection of a steel reinforcing bar in concrete. Three different electrochemical reactions are considered on the steel surface. Charge and oxygen transport are modeled in the concrete domain, where the electrolyte conductivity and oxygen diffusivity depend on the moisture content. The impact of different moisture levels on the corrosion currents is investigated.
This model exemplifies how the rate of steel corrosion in an oil platform increases over time due to build-up of a resistive film on the sacrificial anodes, formed by reaction products. The model also includes secondary current distribution electrode kinetics on the protected steel structure, defining simultaneous metal dissolution and oxygen reduction (mixed potential).
Galvanic corrosion between two different phases (alpha and beta phases) in a metallic (magnesium) alloy is simulated for a representative cross-sectional microstructure configuration. A key feature in the model formulation is the implementation of both anodic and cathodic regions at the electrode surface using a single boundary represented in terms of the level set function.
Cyclic voltammetry is a common analytical technique for investigating electrochemical systems. In this method, the potential difference between a working electrode and a reference electrode is swept linearly in time from a start potential to a vertex potential, and back again. The current-voltage waveform, called a voltammogram, provides information about the reactivity and mass transport ...
Mass transport limitations within thin crevices can often result in the local electrochemistry to differ significantly between the crevice opening (mouth) and end (tip), and as a result of the differences in local chemistry, corrosion may occur. This example models crevice corrosion of iron in an acetic acid/sodium acetate solution. The model reproduces the results of Walton.
This example extends the corrosion protection system analysis of the single oil platform example by modeling the influence of multiple oil platforms placed in an array. The use of the Current Distribution on Edges, BEM interface significantly reduces the problem size and computational time by modeling all electrodes as cylinders along the edges of a wireframe geometry.
At the electrode-electrolyte interface, there is a thin layer of space charge in a diffuse double layer. This may be of interest when modeling devices such as electrochemical capacitors and nanoelectrodes. This tutorial example shows how to couple the Nernst-Planck equations to the Poisson equation, in order to describe diffuse double layer according to a Gouy-Chapman-Stern model. The physics ...
Impressed current cathodic protection is a commonly employed strategy to mitigate the ship hull corrosion where an external current is applied to the hull surface, polarizing it to a lower potential. In this model, the effect of propeller coating on the current demand is demonstrated.
The use of Aluminum (Al) isolator is a commonly employed mitigation strategy for galvanic corrosion between magnesium alloy (Mg) and mild steel (MS). The present model demonstrates the effect of Al isolator thickness on galvanic corrosion severity using a parametric study. The electrode kinetics is implemented here using the experimental polarization data available in literature.
Electrochemical impedance spectroscopy (EIS) is a common technique in electroanalysis. It is used to study the harmonic response of an electrochemical system. A small, sinusoidal variation is applied to the potential at the working electrode, and the resulting current is analyzed in the frequency domain. The real and imaginary components of the impedance give information about the kinetic and ...