A STUDY OF LIQUID JETS FORMED BY BUBBLE COLLAPSE UNDER SHOCK-WAVES INELASTIC AND NEWTONIAN LIQUIDS

This paper describes a study of the formation of liquid jets in elasti c and Newtonian liquids. The technique used to study this phenomenon i nvolves a shock wave, emanating from the collapse of a cavitation bubb le, which causes a gas bubble underneath the free surface of a liquid column to collapse, thereby producing a liquid jet. A comparison of th e jets formed by commercial multigrade motor oils and their Newtonian counterparts shows that, in the former, liquid jet production is marke dly suppressed, with up to an order-of-magnitude reduction in length b eing recorded. Similar findings are made when elastic 'Boger' liquids and their Newtonian counterparts are compared. (C) 1998 Elsevier Scien ce B.V. All rights reserved.