CFD-simulation of different bubbly flow situations applying the Euler-Euler framework


CFD-simulation of different bubbly flow situations applying the Euler-Euler framework

Krepper, E.; Lucas, D.; Rzehak, R.

A widely used approach to model two-phase bubbly flows for industrial applications is the Eulerian two-fluid framework of interpenetrating continua. The loss of details caused by the averaging procedure has to be compensated by consideration of additional closure relations. These concern the momentum exchange between the phases, the effect of the bubbles on liquid turbulence and bubble breakup & coalescence. A set of best available sub models was assembled (Rzehak and Krepper, 2013, 2015). To ensure the predictive capabilities it has to be shown that this model framework is able to describe different flow situations without any changes of model parameters.
The present contribution starts with validation work on upward turbulent bubbly flow in a vertical tube at the MTLoop facility using the wiremesh technique. A second step is the extension to counter-current and co-current downward flow at ROFEX using fast X-Ray tomography (Krepper et al. 2016). Both facilities were operated in Helmholtz - Zentrum Dresden-Rossendorf. Data on the cross sectional distribution of gas volume fraction, of gas and liquid velocity and on bubble size distributions were gained.
The presentation shows the capability of an unified framework of closure relationships to describe different flow situations.

Keywords: CFD; momentum exchange; bubble induced turbulence; fixed polydispersed flow

  • Lecture (Conference)
    The 3rd International Conference on Numerical Methods in Multiphase Flows, ICNMMF-III, 26.-29.06.2017, Tokyo, Japan

Permalink: https://www.hzdr.de/publications/Publ-26089
Publ.-Id: 26089