Magnetic field tomography on two electrically conducting fluids

A cylindrical cell containing GaInSn alloy and aqueous solution of KOH, a highly simplified aluminium reduction cell, is constructed. A direct current is applied to the cylindrical cell to generate the magnetic field. In a range of amplitude and frequency of vertical vibration, a stable, non-axisymmetric wave pattern is produced, and the displacement of the oscillating interface is measured by a digital camcorder. The perturbation of the magnetic field caused by the non-axisymmetric interface is measured by fluxgate sensors and processed by fast Fourier transforms. The measurements are consistent with forward calculations, and have been exploited to reconstruct the deformed interface by solving an inverse problem so as to develop magnetic field tomography to reconstruct an unknown interface between two electrically conducting fluids.