THERMOCAPILLARY FLOW IN LIQUID BRIDGE UNDER MAGNETIC FIELD GENERATED BY COMBINED COIL CONFIGURATIONS

In order to optimize convection control in a liquid bridge, the effects of the magnetic fields generated respectively by axial coils, transversal coils and their combination on thermocapillary flow are investigated. The results demonstrate that the magnetic field produced by axial coils can help suppress melt flow in the radial direction and improve the axisymmetry of a convection structure; and that the magnetic field produced by transversal coils, however, may break the axisymmetry of a convection structure while damping melt flow in the axial direction. Furthermore, the coupled favorable effect, weakened melt flow in the axial direction with an axisymmetrical convection structure, is obtained under the magnetic field produced by the combination of axial coils and transversal coils, thereby attaining a better effect on melt convection, and therefore high-quality crystal in floating zone crystal growth.