The Measurement Of Hydrodynamic Parameters And Cfd Simulation Of Gas-Liquid Flow Behaviols In A Pressurized Bubble Column

The characteristics of gas-liquid flow are investigated in a bubble column reactor with300mm diameter and6600mm height under elevated pressures using conductivity probe measurements and electrical resistance tomography (ERT). In all the experiments, air is used as the gas phase and tap water as liquid phase, where the gas velocity is varied from0.119m/s to0.312m/s and pressures is varied from0.5MPa to2.0MPa. The effects of operation conditions on the radial distribution of gas hold-ups, bubble swarm rising velocities and Sauter mean diameter are discussed. The results show that the gas hold-ups, bubble swarm rising velocities and Sauter mean bubble diameter increase constantly with the increase of the superficial gas velocity. Moreover, there is a maximum gas hold-ups, bubble swarm rising velocities and Sauter mean bubble diameter at the centre of cross-section. The gas hold-ups increase constantly with the increase of the system pressures, but decrease for bubble swarm rising velocities and Sauter mean bubble diameter. According to experimental results, an empirical correlation of the radial gas hold-ups is also presented.Including, simulate the bubble column using CFD models. In the simulations, Euler-Euler model, standard k-ε model and population balance model (PBM) which predicted bubble size changes characterized are incorporated into the simulations. The time-averaged gas/liquid velocities and local gas hold-ups obtained from the simulations are good agreement with measured data. The liquid velocities increase with the increase of the superficial gas velocity and system pressure, and the direction of liquid velocity changed in the range of0.6<r/R<0.8, and the inflection point position are more near the wall with the increase of the superficial gas velocity. These characteristics are good agreement with the literatures.