A stochastic model for prediction of Erosion-oxidation interaction on boiler grade steel Surfaces

Abstract

The simultaneous action of high temperature oxidation and mechanical erosion on the boiler component fabricated using various boiler grade steel comprises of a composite mechanism of degradation of material which has significant techno-economical ramification. A mathematical model has been developed to study the oxidation-erosion process in which, oxidation is treated deterministically and erosion is described from a stochastic point of view. Oxidation is treated with a power law dependence on scale thickness and time. Erosion is treated stochastically as a spatially random event on the oxide surface. This model can be applied to characterize erosion-oxidation interaction on the steel surfaces of plant components. The model incorporates necessary details relative to the oxidation process and to individual erosion events. The treatment of oxide scale erosion as a stochastic process has been incorporated as a fundamental idea to characterize the oxidation-erosion interaction phenomena, which includes explicit details relative to the ‘erodent flux’ and the erosion ‘footprint’. Although the model does appear to be physically reasonable, improvements can be made on the basis of critical data generated from controlled experiments.