A Mathematical Model To Characterize Erosion Behaviour Of Boiler Grade Steels Impacted By Fly Ash In Coal Fired Power Plants

Abstract

A first principle based theoretical model has been developed on the erosion behaviour to predict erosion rates on the boiler components at room and elevated temperature. This model embodies mechanisms of erosion involving cutting wear, plastic deformation wear and effect of temperature on the erosion behaviour. Various grades of steels used in the fabrication of boiler components in conjunction with published data pertaining boiler fly ash has been used for modelling the process .The erosion sensitivity of silica content of fly ash, impact velocity, angle of impingement and variation of steel surface temperature have been studied to characterize the erosion behaviour. The model has been implemented in a computer code to predict the erosion rates at room and elevated temperature for various grades of steel used in boiler components. The model predictions have been found to be in good agreement with the published data, which depicted that minor increase in silica level in the ash can considerably enhances the erosion rate.