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A destabilizing vertical temperature gradient and a rotating magnetic field have been applied to a cylindrical column of liquid gallium. The convective flows which arise as a function of these parameters are identified. For small magnetic field strengths, a regime of stationary flow is observed. This regime is bounded by critical values of the Rayleigh and magnetic Taylor numbers. As the rotating magnetic field is increased, the critical Rayleigh number can increase by more than a factor of 10. The rotating magnetic field itself induces an instability at a critical value of the magnetic Taylor number independent of the Rayleigh number. The nature of the bifurcations (whether subcritical or supercritical) and the convective flows occurring at the critical Rayleigh numbers are dependent upon the magnetic Taylor number. For small magnetic Taylor numbers, the experimental observations are consistent with the occurrence of a single asymmetric meridional roll which is driven around the cylinder by the rotating magnetic field.

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An axially traveling magnetic wave can be used to induce a meridional base flow in a cylindrical zone of an electrically conducting liquid, such as a crystal growth melt. This flow generated non-intrusively can be conveniently controlled, in magnitude and direction, to derive potential benefits for crystal growth applications. In particular, it can be used to effectively stir the melt in long cylindrical columns. It can be used to modify the species concentration field and the thermal field (to some degree) in the melt and to also affect the interface shape of the growing crystal. The basic theory of such an application is developed and preliminary data from a model fluids experiment, using a mercury column, are presented.