Pore-Scale Analysis of Evaporation and Condensation Dynamics in Porous Media

We developed analytical models for surface- and capillary-assisted condensation and evaporation dynamics considering phase-change behavior in idealized wedge-shaped pores and in adsorbed liquid films as building blocks for condensation and evaporation in granular media. Phase-change rates are important for dust mobilization and deposition, vapor transport through partially saturated media, and for residence times of emitted combustion particulates. The basic wedge-film solution was scaled up to represent 3D transient evaporation and condensation processes within an assembly of rough spherical particles. Model comparisons with experimental data for evaporation from a single meniscus and condensation rates into sand samples show consistent agreement for a range of media and ambient conditions.