Abstract
Dispersing fine particles of refining agents uniformly into a molten metal bath plays an important role for enhancing the efficiency of metal refining processes such as the desulfurization process. The densities of the particles are usually smaller than that of the molten metal. Water model experiments are carried out in this study to understand the dynamic behavior of the particles. Low-density spheres made of polypropylene are chosen as the model particle and vertically dropped onto the surface of a water bath. The wettability of each sphere is changed by coating water repellent on its surface. An air cavity is formed behind the sphere under a certain condition. The maximum cavity depth, the time required for the cavity to break up, and the maximum penetration distance are measured using a highspeed camera and compared with their respective empirical equations proposed previously for a single poorly-wetted sphere. These quantities can be correlated in terms of the Froude number similitude.
