Numerical Investigation of Oxide Layer Growth of Stainless Steel LBE at a Mesoscopic Level

Abstract

The corrosiveness of LBE, as an ideal coolant candidate in reactors and accelerator driven systems (ADS), presents a critical challenge for safe applications. One of the effective ways to protect the materials is to form and maintain a protective oxide film along the structural material surfaces by active oxygen control technology. The oxidation process of metals in lead bismuth eutectic (LBE) environment is investigated numerically at a mesoscopic scale. An improved stochastic cellular automaton model based on an improved Moore neighborhood is proposed to investigate the development of a continuous oxide layer of metals in LBE. The ionization of metal and the oxidation reaction were simulated with consideration of the transport of oxygen along the grain boundary and the diffusion of metallic ions. The model was benchmarked with a pure diffusion process, both with the analytical solution and with the previous work. Significant agreement was reached between the data. The developed model is also mapped with the experimental data from an LBE loop. A parametric study was conducted in order to check the importance of the main explicit parameters of the mesoscopic model. The boundary condition at the far end of the specimen has been investigated for the CA model.