Abstract
Bubble column reactors are frequently applied to chemical plants and other industrial plants. To elucidate the practical properties of the bubble columns, the heat and mass transfer phenomena in consideration of the average bubble diameters and average void fractions have been investigated. Although the macroscopic flow structure and the fluctuation over a long time can be well-described, knowledge of microscopic and instantaneous flow structures is still insufficient experimentally and numerically. To solve this long-pending question, an optical fibre probe (OFP) is very useful practically. The OFP measures bubble diameters, velocities, and local void fractions simultaneously. Because of its intrusion, the OFP can successfully measure bubbles even in cases of high bubble density. Still, the OFP remains the measurements for laboratory conditions.
In this study, we originally analyse practical signals of a Single-Tip Optical fibre Probe (S-TOP) in a bubble column measurement. One of the authors already developed a numerical simulator, i.e. a ray tracing simulator. It rationally and quantitatively analyses optic signals delivered from the S-TOP. By using this, we can rapidly improve the S-TOP measurement. We discuss potential of this simulator through analysis of signals of bubble measurement in a large bubble column.
First, the S-TOP measurement in a bubble column (approximately 380 mm in diameter and 1500 mm in height) was conducted. Second, the analysis for obtained signals was conducted numerically and empirically. Finally, we discussed practical performance of OFP for the bubbly flow measurement based on the analytical results.
