[rock_md]

Hello, good day.

I'm doing my master degree about water desalination by solar stills with phase change materials in the bottom. Right now I'm trying to run the simulation without PCM and whole "interesting" part is that I'm not using any multiphase models or evaporation-condensation equations Fluent has (using only UDFs, but that's another topic).

The thing is that when I run the simulation in order to get the mass fraction of water, I received an error message: "Species are not solved in neighbor cell threads" and ID of cells and boundary conditions referenced to this problem. I was reading an article that considered the water and the mixture vapor-air interface as a coupled wall, however I don't know how it will work as a wall or how to setup this in Fluent. For example I made the coupled wall for the glass and mixture interface but I don't know if it is possible to do this in a fluid-fluid interface.

I'm attaching the geometry and the mesh:

https://ibb.co/xFhc4Hc

https://ibb.co/TcqwVBk

And this is a snippet from the article I mentioned before:

https://ibb.co/28XPbDm

I believe there is something about the geometry or meshing setup. For the fluent, I activate the energy, species, radiation and turbulence models and indicate the cells for water, mixture and glass, and when I try to initialize the simulation I receive the error above with bold letters.

I will appreciate your help. I don't know if I was clear enough.