Characteristics of Iron Droplet Ejection Caused by Gas Bubble Bursting Under Reduced Pressure

Bursting of gas bubbles on the free surface of liquid iron produces iron droplets that are ejected into the surrounding atmosphere. The influence of the freeboard pressure on gas bubble bursting was investigated by collecting and measuring the formed droplets in water and in liquid iron systems. In water model, it was found that gas bubbles expanded markedly during the floating up when the freeboard was evacuated but the influence of the freeboard pressure on the mass of ejection is not significant when the freeboard pressure varied from 0.01 to 0.1 MPa. Besides, in steel melt, the mass of ejection was increased by 2-3 times when the pressure was reduced from atmospheric pressure to 66.5 Pa.