Modeling Effective Water Vapor Transport and Subsequent Coarsening in Snow: A Rigorous Upscaling Approach
Dr. Quirine Krol (MSU Magnetic Resonance Laboratory)
4/18/2024 3:10pm
Abstract:
Snow comprises a collection of sintered ice crystals, forming a two-phase porous medium consisting of ice and vapor. Environmental boundary conditions such as gravity and natural temperature gradients throughout the snowpack induce water vapor diffusion. This flux acts as sinks and sources for recrystallization processes, leading to complex morphological changes known as snow metamorphism. Recent modeling and simulation advances have provided effective vapor transport and a rigorous model for morphological changes as a function of the local mass-transfer coefficient. By integrating this mathematical model, 3D microtomography time series, and finite element simulations for heat and mass transport, an estimate for the mass transfer coefficient can be determined. This estimate varies depending on the snow type and the stage of metamorphism, which is expected due to the complex kinetics of the vapor-ice phase transitions and the configurations of underlying ice lattices. Preliminary results from a simpler pore-network model align with these findings but offer more physics-based insights into two origins of coarsening in snow: self-similarity and preferential grain growth, leading to the irreversible selection of fast-growing grains.