Plunging jet entrainment is a highly efficient mechanism for producing large gas-liquid interfacial areas. Applications include minerals-processing flotation cells, waste-water treatment, oxygenation of mammalian-cell bioreactors, riverine re-oxygenation weirs and the understanding of plunging ocean breakers. While detailed air-water flow measurements were conducted in a two-dimensional plunging jet, most studies of air entrainment processes at circular plunging jets have been qualitative. It is understood that plunging jet entrainment takes place when the jet impact velocity exceeds a critical velocity. For larger jet velocities, the developing region of plunging jet flow is subjected to strong interactions between the entrained air bubbles and the momentum transfer mechanism.
This video presents the latest development in air entrainment at vertical plunging jets.
CHANSON, H. (1997). "Air Bubble Entrainment in Free-Surface Turbulent Shear Flows." Academic Press, London, UK, 401 pages (ISBN 0-12-168110-6).
CHANSON, H., AOKI, S., and HOQUE, A. (2004). "Physical Modelling and Similitude of Air Bubble Entrainment at Vertical Circular Plunging Jets." Chemical Engineering Science, Vol. 59, No. 4, pp. 747-754 (ISSN 0009-2509).