Motion Measurement of Rising Bubble Trains in Cylindrical Pipe

Abstract

In this paper, authors have applied PTV and PIV techniques to measure behaviors of rising bubble and induced flow in a vertical cylindrical pipe.
The bubbles rise in regular space from a bottom nozzle of the pipe filled with silicone oil. In the experimental conditions, Reynolds number is from 0.8 to 1.0 at the diameter ratio 0.25 of the bubble to the pipe. Bubbles are pictured from front and side directions by two CCD cameras. By analyzing individual pictures, shapes and dimensions are obtained. From the analysis of sequential pictures, velocities of the bubbles and the flow are measured. The data enable to estimate apparent drag coefficients of the rising bubbles.