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Examines the numerical stability and characterization of flow induced by transverse rotating magnetic fields in cylindrical containers. Generation of Taylor vortices in infinite cylinders; Occurrence of instabilities at low magnetic inductions; Effects of pressure gradient imbalance and centrifugal force on flow.

Abstract: We present a numerical investigation of general flow features in a Ge floating zone, which was performed by using a commercial finite element program FIDAD™. The results demonstrate that for fluids with a very small Pr number the influence of buoyancy forces cannot be ignored in a numerical model. The transition of a steady axisymmetric flow to a time-dependent flow in the Ge floating zone (Ma =125 and Pr =0.007) can be clearly attributed to the interaction between the buoyancy flow and the surface flow. The time-dependent buoyancy–thermocapillary convection was purely hydrodynamical. The thermocapillary convection causes an increase of the average flow velocity from 4.07cm/s to 5.07cm/s. Due to the small Marangoni and Prandtl numbers as well as the stabilization effect of the buoyancy convection, the temperature fluctuations were smaller than 1°C in the melt and 2°C at the free surface. [Copyright &y& Elsevier]