Towards a unified approach for modelling uniform and non‐uniform bubbly flows

An important ingredient of closure relations for the Euler-Euler two-fluid model is the description of turbulent fluctuations. Models proposed in the literature disagree concerning the treatment of such on all scales. The large scale fluctuation structures as well as the bubble induced turbulence might be neglected or resolved and/or modeled respectively in different ways. Each treatment has been demonstrated to work for a certain application but a unifying perspective is lacking so far.
To this end a set of closure relations for the fluid dynamics of bubbly flow has been collected that represents the best available knowledge and may serve as a baseline for further improvements and extensions. This model comprises a set of bubble forces as well as a turbulence model including turbulence modification due to the bubbles and has been successfully validated for bubbly flows in pipes and bubble columns. Here it is applied to two sets of data representing non-uniform and uniform flows in bubble columns which are dominated by large scale fluctuations and bubble induced turbulence respectively.