A corrosion rate model is developed for carbon steel in water containing CO2 at different temperatures, pH’s, CO2 fugacities and wall shear stresses. The model is based on loop experiments at temperatures from 20-160°C. The data are taken from a database containing more than 2400 data points at various temperatures, CO2 fugacities, pH’s and wall shear stresses. To find the best fit of the data, data for each temperature present in the data base was evaluated separately to find typical trends for the change in corrosion rate versus CO2 fugacity, wall shear stress and pH. To facilitate use of the corrosion model a simplified method for calculating wall shear stress in multiphase flow is included. This model includes a viscosity model for dispersions and is developed for oil wet
and water wet flow. Criteria for the maximum production rate to avoid mesa attach in straight sections and behind welds is also included.
Keywords: corrosion modelling, carbon dioxide, carbon steel, mesa attack, wall shear stress