Mechanism of air entrainment by a disturbed liquid jet

It was shown in recent work that the crests of surface disturbances on a fa lling jet are a powerful agent for air entrainment at the free surface of a liquid pool. The paper explores the opposite case in which the jet is dist urbed so as to form an axisymmetric trough, rather than a crest. It is foun d that no air is entrained in this case. The paper concludes with some cons iderations on the validity of a recently proposed model for air entrainment . (C) 2000 American Institute of Physics. [S1070-6631(00)02507-1].