MODELING OF A DIFFUSION CONTROLLING OXIDATION PROCESS WITH SCALE REMOVAL IN OXYGEN-CONTAINING LIQUID FLOW

摘要

A diffusion controlling oxidation model, considering scale removal, is developed in an oxygen-containing liquid flow environment. Scale removal is implemented and the effect of the scale removal rate on the formation mechanism of the duplex oxide layer structure is analyzed in the model. The volume expansion effect caused by density difference is coupled with the weight gain during oxidation. A coordinate transform technique is employed to obtain the diffusion equations with advection term. The governing equations are non-dimensionalized and analogized with the Stefan problem and solved numerically by the finite difference method. The non-dimensional parameters are studied and the model is extended to an oxide growth model with duplex layer structure and noble elements. The model is benchmarked with previous results, and good agreement is obtained.