Dispersion Characteristics of Small Buoyant Particles in a Gas-agitated Vessel

Model experiments were made of the floating and dispersing characteristics of buoyant particles in a gas-agitated water vessel to learn the behavior of inclusion particles in a turbulent flow field of liquid steel. Hollow glass particles were put into the vessel, nitrogen gas was blown from the bottom of the vessel, and the particle concentration was measured by a silicon photodiode. It was found that the concentration of particles in the bulk water increased abruptly at a certain gas-flow rate and saturated at higher rates. This critical gas-flow rate was correlated well with the terminal velocity and vessel geometries. Numerical simulation of the particle dispersion was also carried out using the k-e model and the effect of turbulence on the particle behavior was discussed.