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-   -   compressibleTwoPhaseEulerFoam pEqn missing code for particle pressure (https://www.cfd-online.com/Forums/openfoam-solving/103278-compressibletwophaseeulerfoam-peqn-missing-code-particle-pressure.html)

bruce June 15, 2012 11:28

compressibleTwoPhaseEulerFoam pEqn missing code for particle pressure
 
Hello,

I have found that compressible version of twoPhaseEulerFoam has missing code as shown below, which accounts for particle pressure in solid momentum equation. Which is being accounted in pressure loop.


Code:

    if (g0.value() > 0.0)
    {
        phiDraga -= ppMagf*fvc::snGrad(alpha)*mesh.magSf();
    }

    if (kineticTheory.on())
    {
        phiDraga -= rUaAf*fvc::snGrad(kineticTheory.pa()/rhoa)*mesh.magSf();
    }

The above code is not included in pEqn of compressibleTwoPhaseEulerFoam ! Is this really missing or it is being implemented in different way?

bruce June 23, 2012 13:41

Resolved by commit 5e27d9890131ea032a51bf2d0d0d3fe6ae724673

stern August 14, 2012 07:14

Dear Bruce,

from your post I found that compressibleTwoPhaseEulerFoam is not working well.
Can you inform me at which location the missing a "ppDrag" term has to be included in pEqn.H of compressibleTwoPhaseEulerFoam.

A second question is: Is it possible to simulate an isothermal problem with compressibleTwoPhaseEulerFoam? If not, did you know if twoPhaseEulerFoam is now working well?

Best regards,
Nicole

bruce August 14, 2012 08:54

Hi,

Which version of the solver are you using? There are many recent updates to compressibleTwoPhaseEulerFoam in git version 2.1.x. I have no issues using the latest version.

compressibleTwoPhaseEulerFoam can solve temperature for both phases. But twoPhaseEulerFoam has no such facility. You have two choices while using compressibleTwoPhaseEulerFoam. Set isothermal BC everywhere. Or, comment out temperature solution in the solver and make it cold flow solver.

Best,
Bruce

stern August 14, 2012 09:25

Hi Bruce,

now I use the latest release version 2.1.1

With twoPhaseEulerFoam of previous versions I have bad experiences, because in the freeboard region of a fluidization bed downward high velocities of the solid arise. Because in the release notes of version 2.1.1 nothing about this solver exists, I am unsure if the module twoPhaseEulerFoam was corrected. That is why I decide to work with compressibleTwoPhaseEulerFoam, although my problem is isothermal.

Now, my problem is that after certain time the field "pa" is blowing up in certain cells at the baffle boundary situated in the bed.

Actually, I am looking for a bug-free 2 phase Euler-Euler code, because I am trying since 2 years to use OpenFoam for fluidization problems and after each test I realize that the cod has bugs.

Many thanks for your help,
Nicole

sharonyue April 8, 2013 04:08

Quote:

Originally Posted by bruce (Post 377034)
Hi,

Which version of the solver are you using? There are many recent updates to compressibleTwoPhaseEulerFoam in git version 2.1.x. I have no issues using the latest version.

compressibleTwoPhaseEulerFoam can solve temperature for both phases. But twoPhaseEulerFoam has no such facility. You have two choices while using compressibleTwoPhaseEulerFoam. Set isothermal BC everywhere. Or, comment out temperature solution in the solver and make it cold flow solver.

Best,
Bruce

Hi,

Bruce,can compressibletwophaseeulerfoam works on a tet mesh?
I have tried twophaseeulerfoam but failed.

regards,

Annier July 31, 2013 09:20

is there any tutorials or solved examples on compressibleTwoPhaseEulerFoam
 
i need to learn about compressibleTwoPhaseEulerFoam. are there any tutorials or explanation of examples related to this solver in OpenFoam?

bruce July 31, 2013 09:45

annier,

there are 3 tutorials being shipped with OF. see for example in,

https://github.com/OpenFOAM/OpenFOAM...haseEulerFoam/

but no explanations of problem setup.

Annier August 1, 2013 08:30

thank you
 
Dear Bruce,
thank you very much for your kindness.

Annier August 1, 2013 08:47

my query on the tutorials
 
dear bruce,
the tutorials bubbleColumn and mixerVessel2D are also present in twoPhaseEulerFoam. what codes or files are added in those tutorials of compressibleTwoPhaseEulerFoam inorder to account for the compressibility? it would be easier for me to learn about these tutorials if you would explain me the difference between these tutorials with the same names. thanking you in advance.

bruce August 1, 2013 09:32

Hi, Sorry I ve been away using these solvers for long time. but first you could carefully observe the differences in the problem setup for both cases and come up with general understanding. and later on dig into the differences in the code itself. may be it is easier to start with "fluidisedBed" problem.

Regards,

Annier August 1, 2013 22:53

thank you
 
dear bruce,
thank you very much.

Fine August 11, 2013 16:55

energy equation in compressibleTwoPhaseEulerFoam
 
Hi

Does anybody know what the following two lines in the EEqn.H file of compressibleTwoPhaseEulerFoam mean?

Code:

+ heatTransferCoeff*he1/Cpv1/rho1
      - fvm::Sp(heatTransferCoeff/Cpv1/rho1, he1)

It appears as though the same term is added and then subtracted?

Regards
Josefine


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