1017 Entrainment and Transport of Air Bubbles by a Vortex Ring Launched into Water

Abstract

The entrainment and transport of air bubbles by a vortex ring are experimentally illves − tigated． A vortex 血 g launcher ， composed of a cylinder and a piston， is mounted on the bottom of a water ta 皿 k． Air bubbles are injected from a needle ， which is attached on the cyllnder surface ， into the vortex ring ． The bubble motions relative to the vortex ring are found to be classi 丘ed according to the strength of the vortex ring and the bubble flow rate ． When the s七 rength of the vortex ring is low， the bubbles are 且 ess affected by the vortex ring ． With increasing the strength ， も he bubbles are favorably ep 七 rained into the vortex core and 七 ransported by the convection of the vortex ring ， Key VVords： Vortex ring ， Bubble ， Entrainment aud transport ， Vorticity