Mass Transport by Waves: Bath-Metal Interface Deformation, Rafts Collision and Physical Model

In aluminium electrolysis cells, the interface between molten metal and electrolyte is animated by surface waves. It is well known that there is a permanent deformation of the bath-metal interface (BMI) due to the magnetohydrodynamic force in the cell. Rafts of agglomerated alumina may float on the BMI. A mathematical model was developed to describe the transport of these rafts by surface waves on the BMI. In this study, we examined the impact of the BMI deformation to the mass transport by waves. The mathematical model is validated by a low temperature physical model. Laboratory experiments with rigid objects driven by regular surface waves were performed for a range of amplitude and frequencies. Two immiscible fluids are used to model the electrolysis cell, the interface between water and silicone oil is animated by regular waves. Theoretical model predictions of the object drift motion are compared with the experimental data.