Electromagnetic damping of convective contamination in self-diffusivity experiments with periodic heating conditions

Accurate mass diffusivity values are important in mass transfer processes. Diffusion experiments conducted on earth are typically convectively contaminated due to either thermal or solutal gradients. Liquid metals and semiconductors have high electrical conductivities, and applied magnetic fields may suppress buoyant convection in these liquids. In this paper, an axisymmetric self-diffusivity model is considered in the presence of a steady, strong, uniform axial magnetic field with liquid indium. An isopycnic (radioisotope) tracer is used so that only thermal differences drive the convection. Five different combinations of a steady, uniform heat flux and a steady, periodic heat flux are imposed along the vertical wall while uniform heat loss is allowed through the top and bottom walls of the cylinder. The addition of periodic heat flux with the reduced uniform heat flux has a positive impact on the output diffusivity results for the same applied magnetic field of 5.24 T.