[cwl]

Hi everyone

I am trying to model condensation of vapor on air streams. Case description: 2D axisymmetric cylinder with air inlet at one end (10 C; average velocity 0.3 m/s, set as MassFlow boundary condition), outlet at another end (Pressure outlet boundary condition) and an additional inlet for steam on the wall (50 C; average velocity 3 m/s).

Models: // not all, but the important ones
Implicit Unsteady
VOF: multi-component gas (vapor + air), multi-component liquid (water)
Antoine Equation for Saturation Pressure of Water
Condensation set at Phase Interaction (Primar Phase - water)
Surface Tension
Time-Step 0.01 s // whatever

Without Condensation model set at Phase Interaction everything is fine (see img.); but when this model is turned on - Temperature drops to 0 K at vapor inlet (see img.) and no condensation occurs at all (Volume Fraction of Water is strictly zero everywhere).

I have no idea, why this happens - neither physical explanations, nor computational i've got.

If anyone has any idea or a simple working case of condensation (no film) - i would appreciate yor help greatly.

[Miki12]

Hi cwl,

I'm doing the same kind of simulation, do you try to remove the surface tension model? Do you try with evaporation? I have the same problem as you, I have no creation of water.
I have asked the people from CD-Adapco, they told me to pue at the initial, a very little amount of water.

Do you try with another approach ( fluid film, lagrangian, eulerian-eulerian) ?

Thank you,

Miki,

[raskolnikov]

Do you have any solutions for this problem? I see also no phase change for a same flow simulation.