Bubble Column CFD Model with Effects of Forced Oscillations on Bubble Dynamics

Bubble size distribution has a significant effect on gas holdup, residence time distribution, and mass transfer in bubble column reactors (BCRs). The occurrence of small gas bubbles has potential advantages such as a limited residence time distribution and perfect gas‐liquid phase contact. Gas‐liquid mass transfer in bubble columns can be significantly enhanced by subjecting the liquid phase to low‐frequency vibrations. However, the effect of vibration frequency on bubble formation and hydrodynamic characteristics in BCRs is still not well understood. Herein, a 3D numerical model of a BCR was developed to study the effect of vibration frequency on bubble dynamics under different operating conditions. The Sauter mean bubble diameter was found to be approximately inversely proportional to the vibration frequency.

Eulerian-Eulerian Approach to CFD Simulation of Two-Phase Bubble Column

Calculation work is carried out in the present project to study the effect of different parameters on hydrodynamics of gas-liquid flow by using CFD. The steady state and transient, three dimensional simulations are performed of the whole bubble column for various inlet gas and sparger designs. A standard k-ε is used to describe turbulence occurring in the continuous fluid. Results show he asymmetric recirculation stronger with an increase in the number of holes giving better mixing. The gas hold-up increased with superficial gas velocity but independent of the sparger design at high velocity. Comparison of simulation results with the previous experimental work data has provided a successful validation of the model.