Numerical investigations into two-phase turbulent modalities for bubble column flows

Using the software Fluent, computational fluid dynamic simulations of bubble column flows were carried out in a 3D, unsteady, Euler-Euler framework, combined with a population balance model (PBM), and discussed in connection with laboratory-scale bubble columns, with special attention to two-phase turbulent modalities (TPTMs) representing gas-liquid turbulent interaction. Based on both time-averaged and instantaneous characteristics of the flow fields, including four typical modalities (single-phase, single-phase and bubble-induced turbulence (BIT), mixture, and per-phase) and two rare modalities (mixture-and-BIT, and per-phase-and-BIT), overall, six different TPTMs were comprehensively investigated. The results reveal that the single-phase-and-BIT modality is suitable for simulating bubble column flows. However, the utilities of the single-phase and per-phase modalities are highly consistent, and it is recommended to use them with BIT modification. Besides, the mixture modality is unique compared with the three other typical modalities, and can be used as an acceptable simplified approach.