[bbita]

Dear Foamers,

I am going to solve the multi-component condensation. I already wrote the code for multi-component mass transfer in the presence of K-value at the boundary. I am wondering if condensation is the same thing here which can model with differing K-value at different temperature and pressure.
Besides that, I am wondering how someone would model the condensation of steam in the presence of other condensable gases.
My main problem is that I cannot formulate the problem in terms of boundary conditions and source terms. Any brainstorming is appreciated .

[tom_flint2012]

Hi,


How are you getting on with your problem?



I am solving a similar problem. In my case I use a volumetric dilation source term.
This introduces an error though as you may have the case where in a cell one of the components is condensing and the other isnt, leading to a volume change in the non-condensing phase. I apply a correction step to account for this, but it's messy.

[bbita]

Hi Thomas,

Thanks for your message. I am still working on that. Have you found any solution?

Thanks,

[tom_flint2012]

Yes,

You need to modify MULES and then add a dilation term. I’m currently finalising a manuscript on this. You should also check out the papers of Alex Rattner at Penn state on condensing and evaporating flows.
Once you have modified mules for the state transitions you have to adjust the fluxes to maintain the volume consistency of the non boiling/condensing components ( I have t found a neat way to do this yet, so it’s very clunky for me at the moment)

I’ll share my manuscript draft when I have it in a better state.

[bbita]

Thanks Thomas. Let's say you have two components in your gaseous phase which are going to condense at different temperatures. So I am wondering how you are going to change their concentration in the gaseous phase.

[tom_flint2012]

Hi,

If you are still interested in multiphase condensation, and/or evaporation, I have just had my paper on this subject published. You can find it here:

https://www.nature.com/articles/s42005-020-00462-7

Please let me know if you have any questions. This framework is fully mass conservative. I realised after submission I should have included a plot showing the mass continuity equation is solved perfectly up to a tolerance of 10^-12. Ill show this in a future publication I’m sure. There is a paper on a silver called dropletsmoke++ that shows some of the mathematics you will need to get to my equations.

All the best,

Tom

[Jamessmp23]

Hi Tom,

Congratulations, your paper is interesting.
you seem experienced in OpenFOAM, could you guide me how to apply the mass transfer model in form of Kla to reactingTwoPhaseEulerFoam solver ?

I found only a way to change mass transfer in empirical form.
(Frossling on reactingTwophaseEulerFoam)

Thanks in advanced

[tom_flint2012]

Thanks for the kind words. I don’t know about being too experienced in openfoam. I’m pretty sure I have just tried all the ways to get it wrong by now.

I’m not familiar with that problem. I’m very busy at the moment, but if you post some links to some literature and the equations you are trying to solve I’ll do my best to give you some pointers.
You will have to add the mass transfer terms as explicit/implicit I’m MULES - normally written as Su or Sp in examples I have seen. The mass transfer rate of phase1 -> 2 should be equal and opposite of that from 2->1 to conserve the mass of the system. If there is a density change between the two phases you will have to add a dilation term in the pressure equation also.

A really good start would be to look at interthermalphasechangefoam is SoftwareX by Nabil and Rattner (if my memory serves me correctly) I took a lot of inspiration from this work and the dropletsmoke++ publications.

I hope this helps. If you list some references I’ll try and help further but I really am very busy so can’t promise anything.