Calculation of dissolution/deposition rates in flowing eutectic Pb–17Li with the MATLIM code

It is generally accepted that corrosion of steel components in flowing liquid Pb–17Li is ruled by dissolution/deposition processes. A simple method has been devised to calculate the mass transfer in liquid metal loops. It is based on the use of mass transfer coefficients which determine the mass flux from the wall into the fluid and vice versa. These coefficients depend on a characteristic dimensionless thermo-hydraulic number, namely the Sherwood number, which itself depends under forced convection flow conditions on the Reynolds number and the Schmidt number. This is supplemented by the application of differential equations for dissolved steel components. The dissolution and deposition rates determine then the evolution of the flow channel geometry along the loop and the flow velocity. The newly developed code MATLIM can routinely deal with multi-modular liquid metal loops. Thus, calculations have been done for the PICOLO loop based on iron solubility and diffusivity correlations of Feuerstein et al.