Interdiffusion and convection in high magnetic fields

In liquid diffusion measurements, the main problem is the additional mass t ransport by convection. In the system Indium-Tin, convection caused by dens ity gradients in horizontal and vertical capillaries was characterised, and the magnetohydrodynamic damping was investigated experimentally. While the magnetic field effect on diffusion experiments in vertical capillaries was relatively minor, the damping effect of the magnetic field could be clearl y demonstrated in horizontal capillaries. Comparing these experiments with experiments in microgravity it can be seen that in the investigated system convection was practically completely suppressed by transversal magnetic fi elds higher than 3T. In electrically conducting crucibles, the sample was m ixed by Lorentz forces on account of thermoelectric currents.