{"id":166295,"date":"2022-02-10T19:18:06","date_gmt":"2022-02-10T19:18:06","guid":{"rendered":"\/forum\/forums\/topic\/condensation-modelling-in-fluent\/"},"modified":"2022-02-14T12:35:50","modified_gmt":"2022-02-14T12:35:50","slug":"condensation-modelling-in-fluent","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/condensation-modelling-in-fluent\/","title":{"rendered":"Condensation modelling in Fluent"},"content":{"rendered":"
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Hi,<\/p>\n

<\/p>\n<\/p>\n

I posted to this forum a few week ago but was removed since it was attached to another thread and haven't posted a follow-up so here it is after diagnosis.<\/p>\n

I am trying to model condensation in a 3D domain. I am using the VoF model with Evaporation-Condensation Lee model and have followed set ups from various papers and Youtube tutorials which go through their set-ups (in varying detail) and have been unsuccessful. I have refined my mesh in the ways recommended (inflation layers, control, skewness) and the used a variety of turbulence modelling, boundary conditions and simulation controls (correct patching, time step < 0.005, large iteration number). I noticed that all of the work I have come across which details condensation set ups set up the phases changes in the following way: <\/p>\n

From Phase – Water<\/p>\n

Species – H2O<\/p>\n

To Phase – Water Vapor<\/p>\n

This initially struck me as incorrect since I am trying to model condensation so I should be going from Vapor to Water and not the other way around. So when my simulation failed to show condensation, I adjusted this model to:<\/p>\n

From Phase – Water Vapor<\/p>\n

Species – H2O<\/p>\n

To Phase – Water <\/p>\n

When I hit initialise I get the warning: Latent Heat cannot be less than 0! I tried running the programme anyway to see what would happen and I encountered a floating point exception. After googling on this forum about both the floating point exception and the Latent Heat cannot be less than 0, I made adjustments to my mesh (for the floating point exception) but could not figure out what to do for the Latent Heat is less than zero. I read that is has something to do with material properties not fully defined in fluent but as far as I could see I didn't see anything missing. I will add I am very new to this type of modelling but have a small grasp after a couple months of (mostly) failing.<\/p>\n

<\/p>\n<\/p>\n

TLDR:<\/p>\n

If I am trying to model condensation. In the Evaporation – Condensation model is the arrangement of the "From phase" and "To Phase" important?<\/p>\n

From Phase – Water<\/p>\n

Species – H2O<\/p>\n

To Phase – Water Vapor<\/p>\n

shows no condensation. <\/p>\n

From Phase – Water Vapor<\/p>\n

Species – H2O<\/p>\n

To Phase – Water <\/p>\n

gives a warning of Latent Heat cannot be less than Zero! I am not sure what I am missing in the material properties. <\/p>\n

<\/p>\n<\/p>\n

Screenshots showing Temperature and Volume Fractions in post processing of my most recent set up:<\/p>\n

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