(180a) Prediction of Transition Regime Properties in a Bubble Column Under Various Gas-Liquid Systems

This work studied the determination of flow regimes with various gas−liquid systems in a bubble column. Gas holdup, drift flux, volumetric mass transfer coefficient, and pressure standard deviations were measured to determine the transitional superficial gas velocity. For a low column aspect ratio (H/D=2.5-5), the superficial gas velocity at the transition regime became higher with lower liquid height. At the system with low-density gas, the reverse trend was observed since force balance acting around the bubble changed. In a lower axial position of the column, mass transfer was interrupted by the weak body force and drag force. Regardless of the parameter, the measured transitional superficial gas velocities were similar. Since there has been no accurate correlation to predict the transition regime, the correlations to predict both transitional superficial gas velocity and gas holdup were proposed, and they successfully estimated the transition regime properties within 15% errors.