Multiphase flow in small-gap geometry: A combined numerical and experimental study
Résumé
A joint experimental and simulation study of a gas-liquid flow with non-quiescent liquid is presented, in the case
of a small-gap geometry, such as the ones implemented in nuclear fuel recycling processes to mitigate criticality
issues. The numerical model is based on a Euler-Euler approach that has been selected and tested on existing
data published by Krepper et al. (2007) for the bubbly flow of air in a flat rectangular column filled with
quiescent water.
Thanks to the complementary experimental study implementing full-scale and non-intrusive velocimetry and
granulometry measurements, the effects of the liquid flow rate and of the bubbles polydispersity have been
investigated and the corresponding model's predictions validated based on velocity measurements.
These new results highlight that, although the flow field deviates strongly from the one encountered in the
typical configurations investigated so far (i.e. cylindrical or rectangular bubbly flows columns involving bubbles
injection at the bottom of a quiescent liquid), in this case also, the bubble size distribution plays a major role in
the two-phase flow features and that a proper description of it is needed.