Bubble behavior and evolution characteristics in the RH riser tube-vacuum chamber

Abstract The motion behavior of bubbles in a riser tube is studied in order to analyze the bubble evolution characteristics. Gas distribution and bubble movement in risers and vacuum chambers have important effects on liquid steel flow, mixing and refining process. It is found that the initial diameter of argon bubbles in the riser tube decreased with decreasing vacuum degree. The diameter of argon bubbles in the riser tube increased with increasing gas flow rate. The bubbles could be divided into the single bubble rising zone and the bubble breaking coalescence zone in the rising tube. After the bubbles were blown in, they changed from regular spherical shapes to flat shapes in the single bubble rising zone, and then broke apart into small bubbles in the bubble breaking coalescence zone. Variations in the gas flow rate and vacuum degree had significant effects on the regional distribution of bubble motion and bubble residence time. The critical height of the single bubble rising zone and the bubble breaking coalescence zone were stable when the bubble travel distance was greater than 280 mm.