Dispersed Turbulent Two-Phase Flow

Purpose and focus of SIG

Dispersed turbulent two-phase flows are found in daily-life and in numerous technical and industrial processes. Examples are pollutant transport in the atmosphere, sediment transport in rivers, fuel injection in engines, pneumtic transport, bubble column reactors and spray driers for food processing, to name only a few. Due to the interaction between the phases and the involved different time and length scales such processes are rather complicated and a theoretically based design and optimisation of processes is almost impossible. Moreover, a scale-up is generally not straight forward and quite often experiments at different scale size are required. All these issues initiated the application of CFD to dispersed two-phase flows probably more than 20 years ago. However, for performing reliable numerical computations of two-phase flows detailed models describing the interfacial transport and other relevant elementary processes, as for example, particle-wall collisions, inter-particle collisions, agglomeration and coalescence, are needed. Mostly, such a model development requires detailed experimental information. Nowadays also direct numerical simulation (DNS) with interface resolution has become a very powerful tool for analysing the desired elementary process.

The major objective of SIG 12 is the improvement of numerical predictions of dispersed turbulent two-phase flows and the associated models. This involves the following issues:

• exchange of knowledge and results on elementary processes (experimental data and DNS results)

• development of models for the numerical computation of dispersed multiphase flows and their validation (test case database)

• definition and establishment of detailed test cases on dispersed two-phase flows for code validation

• organisation of workshops on the numerical prediction of dispersed two-phase flows for exchanging ideas and developments

• organisation of summerschools on experiments and numerical prediction for dispersed two-phase flows for the education of PhD students and other scientists from industry and academia

• collaboration with industry related to process design and optimisation