Speaker
Description
A fluid/fluid mass transfer model implemented in computational fluid dynamics (CFD) is presented. This includes the model description, proving and application for a liquid steel/ slag mass transfer within a purged steel ladle. The model considers the prevailing flow as well as concentration and for the flow it distinguishes between laminar and turbulent flow. For the case of turbulent flow, the boundary layer at the liquid/liquid interface is modelled analogous to the wall treatment for species. Interface concentrations are determined by the diffusion equation. Contrary to other presently available mass transfer and reaction models the established model aims the calculation of the mass transfer coefficient depending on the local fluid flow- and concentration conditions. For a case without convection the model is tested by comparison with the solution of one-dimensional diffusion equation. In the ladle case the mass flux density is compared with data from literature. The model is applied for the steel/slag mass transfer in a gas purged steel ladle and it is found that the mass transfer increases with increasing purging rates within a certain range, slag bath heights as well as decreasing viscosities.