Experiments with large diameter gravity driven impacting liquid jets

The phenomenon of a liquid jet released under gravity and falling through o r impacting onto another liquid before colliding with an obstructing solid surface has been studied experimentally under isothermal conditions. Usuall y the jet diameter was sufficiently large to ensure jet coherency until col lision. Direct flow visualization was used to study jets released into wate r pools with no air head space and jets impacting onto water pools after fa lling through an air head space. It is shown that distances predicting the onset of buoyancy and the entrainment of air using derivations from continu ous plunging jets, are not applicable for impacting jets. The morphology of jet debris after collision with the solid surfaces correlates with the wet ting properties of the jet liquid on the surface.