Visualization of Flow Induced by Bubble Dispersion

Bubbles generated successively at the exit of a single-hole nozzle rise upwards independently without any interactions when the gas flow rate through the nozzle is very low. Coalescence of bubbles and breakup of a bubble become to take place near the nozzle exit with an increase in the gas flow rate. As a result, many small bubbles and droplets are produced there. Meanwhile, multi-nozzle gas injection operations are employed in the real materials processes at high temperatures. Three or four nozzles are usually settled on the bottom wall of the reactor. A bubbling jet is formed above every nozzle. Interactions occur among the bubbling jets under certain conditions through the Coanda effect. In this chapter, some topics in relation to bubble interactions are introduced.