Abstract
This study was experimental investigation of the process of development of a bubble swarm and tries to clarify its relation to motion of liquid phase. The bubble swarm and its surrounding liquid motion were measured via high-speed CCD cameras and LDA system, respectively. As the bubble swarm progress, following bubbles are accelerated by the wake of preceding bubbles, and it caught up with preceding bubbles. Furthermore the members of the bubble swarm were dispersed. On the basis of the frequency analysis of the bubble motion in the bubble swarm and that of the liquid phase motion, a characteristic frequency has been found owing to the center of gravity motion of the bubbles.
