[Fabri91]

Hello! As part of my thesis I have to run some simulations concerting evaporation of a small pool of water inserted in a slow airflow, in order to compute a theoretical evaporation rate.

The problem is setup as a 2D problem, with one phase made up of liquid water and the other made up of a mixture of water vapour and air, using the VOF multiphase model and the Evaporation-Condensation mass transfer mechanism to account for evaporation, with air as the primary phase and water as the secondary one, with the intent of setting the evaporation/condensation frequency based on experimental data.


Right now I'm dealing with these two issues:
- I'm not sure how to setup the evaporation-condensation model in this particular instance: I assume that setting mass transfer from "water" to "air" would be incorrect since this wouldn't take into account the relative humidity in the gaseous phase, but I haven't been able to find resources as to the proper way to set this type of problem up. Any pointers in this regard would be greatly appreciated.

- I don't know how to obtain the output of the overall evaporation rate: I tried saving to file the volume integral on the entire domain of the mass transfer due to evaporation-condensation (under the "monitors" item in the "Solution" tab), but even in the simulations where simply seeing the animation of the volumetric fraction of the liquid water phase reveals that evaporation has taken place, the relative .out file has an output of 0, so I assume that I'm misunderstanding something here in a fundamental manner.