Behavior of a Cavitating Submerged Water Jet

Abstract

It is known that high speed and intermittent protrusion occurs on the surface of a cavitating submerged water jet. In the present report, particularly, protrusion which arises between the exit of a nozzle and the 1^<st> peak area is focused and photographed by a high-speed-video-camera in order to measure the protrusion velocity. Consequently, it is found that such high speed protrusion is in a supersonic state because the sound velocity is extremely declined under the influence of the void fraction around a submerged water jet. It also emerges that the interfacial behavior of such protrusion differs remarkably with the forms of the nozzle and the values of the injection pressure.