Abstract:
Multiphase flows are commonly encountered in industrial processes but remain
challenging to predict. The role of droplets in the setting of various flow patterns
seen in pipes is capital. Being able to simulate accurately the motion, the dispersion,
the deposition and the entrainment of droplets from a liquid film or pool
would allow refining the various numerical models and would provide a useful
insight to people involved with such flows. The PhD work summarised in this
thesis aims at answering that ambitious goal, i.e. to reproduce the whole "life"
of a cloud of droplets, with application to pipes and industrial systems. To the
author’s knowledge, such study has never been realized with any open source
computational fluid dynamics code such as OpenFOAM and in such details. An
original surface-tracking motion has also been developed to solve wavy-stratified
flows and droplets entrainment by extending OpenFOAM’s capabilities. The Lagrangian
framework has been selected for this study as the relationship with
various forces could be expressed directly and statistical information, including
any Eulerian field if needed, could be retrieved.
