Experimental Studies of Hydrodynamics and Regime Transition in Bubble Columns

Abstract

The detailed flow structures in bubble columns with and without internal draught tube have been investigated using the PIV technique. The onsets of transition due to vortex formation and different flow patterns with and without draught tube have been studied using the drift‐flux model and the experimentally measured Reynolds stresses. The role of solid particles and liquid viscosity, as well as bubbling orifice configuration on the flow patterns and regime transition has also been studied and discussed.

Determination of Liquid Multiscale Circulation Structure in a Bubble Column by Tracing the Liquid Flowing Trajectory

“…It means that under the uniform liquid flowing condition there also exists a macroscale liquid circulation loop in the column. Such an observation is just on the contrary to the results reported in a number of studies − but is consistent with the findings of Hills and other workers. , This may be due low gas flow rates; although the flow is uniform, the rising gas bubbles may move upward not in a straight line but in a spiral manner or in a meandering way, , which will also carry liquid upward in their wakes, thus inducing the convective circulation flow of liquid. It should be noted that the motion of liquid circulation flow under this condition is not vigorous and the liquid circulation velocity is much slower compared with that under the churn turbulent flow regime.…”

New methods for flow regime identification in bubble columns and fluidized beds

“…Zahradník et al (1997) studied the duality of the flow regimes in bubble columns. Thet et al (2006) performed good experimental studies on hydrodynamics and regime transitions in bubble columns. An interesting method for flow regime identification in high-pressure bubble columns has been presented by Lin et al (1999) All researchers reported that the mode of primary gas dispersion (bubbling regime) may essentially influence the character of the gas-liquid bubble beds and the respective values of its hydrodynamic and mass transfer characteristics.…”

Past and current components-based detailing of particle image velocimetry: A comprehensive review

“…Thet et al [ 65 ] investigated hydrodynamics and regime transition in bubble columns. In the study, experiments are carried out with and without an internal draught tube.…”