Diffraction Contrast Tomography, Metamorphism of snow and Phase field modeling of kinetic faceting
Diffraction Contrast Tomography, Metamorphism of snow and Phase field modeling of kinetic faceting
Thesis defence

Thèse de Rémi Granger

on the 17 December 2019
Crystal growth physics in dry snow metamorphism: Characterisation and modeling of kinetic effects

The main objective of the thesis is to improve our understanding of faceting occurring during dry snow metamorphism. The thesis focuses on the interplay between heat and mass diffusion, and kinetic effects in the context of snow. For the first time, Diffraction Contrast Tomography (DCT) has been performed to monitor an experiment of temperature gradient metamorphism. The technique permits retrieval of the crystalline orientation of the grains constituting the microstructure of the sample. Links between orientation of crystals and mass fluxes were analyzed.

The study shows that kinetic differences between basal and prismatic faces have effects on phase change fluxes at the ice/air interface. From a numerical modeling point of view, a highly anisotropic kinetic coefficient has been taken into account for the evolution of the ice/air interface. The model uses the phase-field approach and couples phase changes to heat and water vapor diffusion.

The model was compared to an experiment of air cavity migration under a temperature gradient in a monocrystalline ice block monitored with X-ray microtomography, and to the growth of a negative crystal during a pumping experiment followed with optical microscopy. Such anisotropy permits reproduction of the observed faceting.
Finally, the potential of the proposed model to describe snow metamorphism is highlighted.


Ian Baker, Professor, Thayer School of Engineering, Dartmouth College, USA
Etsuro Yokoyama, Professor, Computer Center, Gakushuin University, Japan
Wolfgang LUDWIG, Directeur de Recherche, INSA Lyon
Luc SALVO Professor, Grenoble INP
Christian GEINDREAU, Professor, Université Grenoble Alpes, supervisor
Frédéric FLIN researcher, CNRM/CEN, supervisor


Saint-Martin-d'Hères - Domaine universitaire
Laboratoire LEGI, amphitheatre K118, bergès site, 1209 Rue de la Piscine, 38610 Gières.
Mis à jour le 10 December 2019