溶融金属の波動抑制に及ぼす表面に垂直に印加された直流磁場の効果

抄録

The surface wave of molten metal is a triger to induce instabilities and surface defects in several processes such as twin roll, electromagnetic casting and conventional continuous casting.
Molten metal is an electrically conducting fluid. So its surface wave motion is expected to be suppressed by imposing direct magnetic field.
In this work, a direct magnetic field was imposed vertically to surface of liquid mercury and damping behavior of wave motion was measured by using laser slit beam. On the other hand, a damping coefficient of wave motion was derived on the basis of magnetohydrodynamics, and experimental data verified the theoretical results. Magnetic field intensity to completely suppress wave motion of molten steel is evaluated by use of the dispersion relation and the damping coefficient derived here.