Formation of air bubbles at orifices submerged beneath liquids

The results of two investigations are reported. Air bubbles were formed at orifices submerged beneath each of fourteen liquids. The surface tension of the liquids varied from 17.8 to 72.4 dynes/cm., and the viscosities ranged from 0.436 to 713 centipoise. In the first investigation, air bubbles were formed at orifices at various angles of inclihation. Orifice diameters ranging from 0.159 to 0.396 cm. were employed. The air‐flow rate was varied from 0.1 to 100 cc. (at standard conditions)/sec. The results were obtained with two different apparatuses by three independent investigators. In the second investigation, the effect of the velocity of a liquid flowing past a horizontal, submerged orifice on the formation of air bubbles was determined. Liquid velocities ranging from 0.34 to 2.5 cm/sec., which spanned the region of laminar flow, were employed. Orifice diameters ranged from 0.15875 to 0.3175 cm., air‐flow rates from 0.5 to 100 cc/sec. (at standard conditions). It was found that the bubble formation observed in each of these investigations could be correlated with the physical variables of the system by the application of Newton's second law of motion to the bubble at the instant just prior to its release from the orifice.