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andrea.pasquali January 19, 2012 06:31

incompressible thermo type (in buoyantSimpleFoam)
Hi all,
I'm trying to compile the buoyantSimpleFoam with basicRhoThermo type to use the <incompressible> prop. to run simulation with water liquid (I saw this set up in chtMultiRegionLiquidFoam).
I tested the chtMultiRegionFoam with <incompressible> thermo type for liquid water and it work well, but it is transient. I want steady. So I tryied the chtMultiRegionSimpleFoam with <incompressible> thermo type and it crashes in hEqn because it divide rho/psi where psi = 0 !
If I use the hEqu of buoyantSimpleFoam it works but the temperature field is not solved !
Why the chtMultiRegionSimpleFoam with <incompressible> thermo type does not work? Should it work?
Did anyone meet this problem?
Thanks for any help, Andrea

andrea.pasquali January 20, 2012 12:25

1 Attachment(s)
in the hEqn I changed the term "rho/psi" with "p" (they have same dimensions).
Now it works but I think the T is not well solved.
I attached the same model solved with buoyanPimpleFoam (bottom) and buoyantSimpleFoam modified (top).
Note that for both I'm using basicRhoThermo type <incompressible> and I added porous medium.

Thanks for any suggestion


jaromin January 25, 2012 09:17

Hi Andrea,

You show here results for a case using buoyantPimpleFoam with the basicRhoThermo type <incompressible>. I also tried the same configuration, but convergence is terrible. There may be many reasons for bad convergence of course, but I am wondering if you also faced any convergence problems here. Have you made any changes to buoyantPimpleFoam?

About the buoyantSimpleFoam, the default thermo type is basicPsiThermo. What kind of changes have to be made to run here basicRhoThermo type <incompressible>?

Thanks for any answers.

andrea.pasquali January 25, 2012 09:49

Hi Maria,for pimple I did not find any strange problem. I used incompressible thermo type (check the multiRegionLiquidHeater tutorial).
You are right, for thesimple the default thermo type is the basicPsiThermo type. I changed it in the .C / .H code adding the basicRhoThermo.
But, as you can see from my results, I think this is not enough!
Let me know if you are going on with this,

aujamal20 November 21, 2013 07:42

Hello OpenFOAMers,
I am trying to run a multiRegion case using chtMultiRegionFoam solver and using icoPolynomial equationOfState for fluid region and its not working.
I want to use chtMultiRegionFoam with <incompressible> thermo type for fluid region and to use icoPolynomial for temperatur dependent properties. Please let me know how I can do this. I mean where and what modification are required.


Tobi November 21, 2013 07:46

Hello Asad,

it should be possible just to use icoPolynomial to set your fluid.

aujamal20 November 21, 2013 09:43

Helli Tobi,
Thanks for your immediate response. I have been using following thermotype for fluid region


type heRhoThermo;
mixture pureMixture;
transport polynomial;
thermo hPolynomial;
equationOfState icoPolynomial;
specie specie;
energy sensibleEnthalpy;
and in the start simulation does not show any error but its just stops after some itterations--> courant number shoots up to several hundreds and simulation stops. I also checked my pressue BC they seemed quite reasonable.
I just cant figure out what is wrong with my case...

aujamal20 November 21, 2013 09:50

0 folder of my case...
1 Attachment(s)
please find attached a 0 folder of my case and please let me know if there is any problem BCs.

Tobi November 21, 2013 16:10

I can not find any error in U,p and p_rgh.
Well I wanted to simulate a coat store like that one without success.

My problem was the p and p_rgh initialisation.
After a few modification it was posible to solve my problem with steady state conditions but not with transient solver.

Maybe you find any hints in that thread:

especially with the p and p_rgh initialisation

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