Effect of orientation of the orifice plate on the formation of air bubbles at submerged orifices

The formation of air bubbles at orifices submerged below a liquid was investigated. The orifice was oriented at each of several different angles with respect to the horizontal, ranging from zero to ninety degrees. Several liquids were investigated in order to determine the effect of the physical properties of the liquid on the formation of the bubbles. Surface tension was varied from 17.8 to 72.4 dynes/cm. Density was varied from 0.68 to 700 cp. Three orifice diameters ranging from 0.159 to 0.318 cm were employed and the flow rate of the air was varied from about 1.5 to 150 cc/sec. The effect of the orientation of the orifice was found to be small. Newton's second law of motion was applied to the bubble at the instant prior to its release from the orifice. The resultant equations adequately predicted the frequency and volume of the bubbles formed as a function of the physical properties of the liquid and the geometry of the system