3-D PTV Measurement of Bubble-Bubble Interaction Appearing in a Free-Rising Bubbly Flow

Abstract

This paper concerns with experimental measurement of bubble-bubble interaction in a free-rising bubbly flow using three-dimensional Particle Tracking Velocimetry (3-D PTV). An accurate labeling method and a ghost-elimination algorithm are employed to measure correctly the center of gravity for individual bubble so that the relative velocity vector in a swarm of bubbles is captured with high statistic reliability. The bubble-bubble interaction is discussed for an intermediate Re number (Re = 10), where horizontal repulsive and vertical attractive motions are detected with the present experiment.