NUMERICAL COMPUTATION OF METAL OXIDATION PROBLEMS ON BOUNDED DOMAINS

This paper is a study of metal oxidation problems with moving oxidatio n fronts, modeled by Fickian oxygen diffusion through the oxide scale and metal. A numerical algorithm is developed and implemented based on a variable grid finite difference scheme. A domain transformation tec hnique is introduced for the space and time variables, resulting in a transformed problem defined over a fixed domain but with non-linear di ffusion equations. The numerical algorithm is implemented for nominal values of the material constants corresponding to titanium alloys at e levated temperatures. Three different benchmark problems with planar, cylindrical and spherical oxidation fronts are analyzed in this work. Also, the influence of the geometry of bounded domains on moving oxida tion Fronts is discussed. (C) 1998 Elsevier Science Ltd. All rights re served.