2000 Volume 86 Issue 8 Pages 514-518
In continuous casting, the free surface motion of a molten metal plays an important role for determining the surface quality of products. In order to clarify the free surface behavior of a molten metal under the imposition of an intermittent alternating magnetic field, free surface waves of a molten gallium were visualized and recorded by use of a high-speed video camera. It is noticed that the number of capillary waves generated in the radial direction increased with increase of the intermittent frequency and was decreased by inserting a copper shield between a coil and a mold. The number of the waves generated in the azimuthal direction decreased during propagating from the vicinity of a sidewall to the center. Asymmetric gravity waves were excited when the distribution of the magnetic field was non-uniform in the azimuthal direction or the intermittent frequency was adjusted near the resonance frequency.
