Experimental study and modelling of the crystallization of a water droplet

Modelling the crystallisation of a water droplet into a cold humid airflow is the first step in modelling the behaviour of water droplets sprayed out of a snow gun. This modelling, which is based on an experimental study, deals with the behaviour of the droplet which is transformed successively from the supercooled liquid phase to the liquid–solid phase and then the solid phase. These three transformations are brought about by various exchanges: heat transfer with conduction and convection as well as mass transfer with evaporation and sublimation. The supercooling phenomenon is naturally observed during experiments and taken into account in the modelling. La modélisation de la cristallisation d'une goutte d'eau dans de l'air froid et humide en écoulement a pour but d'approcher le comportement d'une goutte d'eau issue d'un canon à neige. Cette modélisation, qui s'appuie sur une étude expérimentale, traite du comportement de la goutte liquide surfondue, liquide-solide et solide, soumise à un ensemble d'échanges par transfert de chaleur (convection, conduction) et par transfert de masse (évaporation, sublimation).