Effect of orifice submergence on bubble formation

The effect of orifice submergence on bubble formation was experimentally studied. Four orifices were used of a diameter equal to 0.115, 0.210, 0.325 and 0.435 cm. Air was used as the gas phase and water as the liquid phase. Experiments were conducted in the range of gas flow rates 0.75-56.7 cm3/s, chamber volumes 150-7000 cm3 and orifice submergence 10-150 cm. Results show that in the region of single bubble formation the bubble size increases with the orifice submergence. In the region of group formation of bubbles the individual bubble size is independent of the orifice submergence, ranging from 0.1 to 0.5 cm3 for the smallest orifice and from 0.2 to 1 cm3 for the other ones. No effect of orifice submergence was observed on weeping.