Air-water flows in water engineering and hydraulic structures. Basic processes and metrology

ABSTRACT: Hydraulic researchers had been leading air–water flow studies until the mid-1950s. Since progresses have been dominated by multiphase flow experts despite the relevance of “white water ” phenomena to hydraulic engineering. In this lecture the writer reviews the basic mechanisms of air entrainment: singular aeration and interfacial entrainment. The relevant instrumentation and data processing technique are detailed. Later recent progresses in unsteady flow measurements and in seawater are discussed.