Calculation of three-phase bubble columns

The scope of this work is the numerical calculation of the three-dimensional, time-dependent velocity and concentration fields in cylindrical bubble columns with two-phase gas-liquid and three-phase gas-liquid-solid flow. Therefore all phases are described by an Eulerian approach. In particular the local interfacial area density and the interphase transfer terms for mass and momentum are calculated based on a population balance equation approach. The proposed approach enables an effective way to couple population balance and computational fluid dynamics. For three-phase gas-liquid-solid flow heavy particles with diameters in the range of 100 mu m are considered as catalyst for a heterogeneous chemical reaction. The solids phase viscosity and pressure are described based on the granular flow theory. The influence of particles on bubble coalescence has been investigated to extend the model. From the calculation the three-dimensional, time-dependent velocity and concentration fields are obtained.