液态钐铁合金中氮气泡的运动行为

Movement Behavior of Nitrogen Bubbles in Liquid Sm-Fe Alloy

对于钢包内底吹气体的精炼方法,通过物理实验和理论计算相结合的方法,研究了液态钐铁合金中底吹氮气泡的运动行为,重点讨论了氮气泡在液态钐铁合金中上浮时的形态。结果表明：液态钐铁合金中,底吹氮气泡生成时的最小压力与外界气压以及吹气管的半径有关;当外界压力一定时,吹气管的半径越小,生成气泡所需的最小压力越大;当吹气管的半径一定时,生成气泡所需的最小压力随外界压力的增大而增大。在常压条件下,底吹氮气泡半径随时间的的增大而增大,实验表明,2.5 s之前,氮气泡的长大速率比较缓慢。同一时刻,压力越大则氮气泡的半径越小,且不同压力下氮气泡的长大速率不同,压力越大,气泡的长大速率越小。

For the refining method of blowing gas from the bottom of ladle, the movement behavior of bottom-blown nitrogen bubbles in liquid Sm-Fe alloy were studied through combination of physical experiment and theoreiieal calculation, and the morphology of nitrogen bubbles during the floating in the liquid Sm-Fe alloy were emphatically discussed. The results show that in the liquid Sm-Fe alloy, the minimum pressure in the formation of bottom blowing nitrogen bubbles is related to the ambient pressure and the radius of blow pipe. When the ambient pressure is certain, the smaller the radius of the blowing pipe is, the bigger the minimum pressure required to generate bubbles is. When the radius of bowing pipe is fixed, the minimum pressure needed to generate bubbles increases with the increase of the ambient pressure. Under normal pressure, the radius of the bottom blowing nitrogen bubble increases with the increase of time. The experiment shows that the growth rate of nitrogen bubbles is slow before 2.5 s. At the same time, the bigger the pressure is, the smaller the radius of the bubble is. In addition, the growth rate of nitrogen bubbles is different under different pressures. The bigger the pressure is, the smaller the growth rate of the bubbles is.