Numerical investigations of bubbles rising in water

The hydrodynamics of rising air bubbles in water filled bubble columns are examined using a transient numerical model following the Euler-Euler method. In this particular case the bubble-size distribution is assumed to be mono-disperse and the influence of this assumption on the specific mass-transfer area is discussed. Additionally, the influence of the bubble size is discussed with regard to the mass-transfer area, the air volume-fraction, and the axial air velocity profile. To validate the numerical model, experimental results from tomographic measurements at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) are used. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)