CFD Online Discussion Forums - Porous media in openfoam

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Mutiphase_Eulerian_Eulerain_porous media

Hi Arturo,

I'm stuck at a packed bed simulation in Fluent. The packed bed model is represented by air/water streams in porous media in Eulerian framework.

I aim at my model to predict pressure drop and liquid volume fraction in the bed.

Kindly let me know,

1) Is viscous resistance needs to be entered for both phase? I've calculated this resistance (1/m2) by Ergun Equation for single phase. But how do we account for two phase here?

I've used "Schiller Naumann" drag law to calculate "interphase coupling" considering 5 mm water bubble dia.

Do you feel it necessary to introduce two momentum source terms instead of entering viscous/inertial resistance?

A technical reply will be highly appreciated.

Regards,

SM

Quote:

Originally Posted by arturo (Post 192404)

BTW I work also with multiphase flows on porous media.

Thnx

Arturo

FLUENT Eulerian packed bed model can be seen as a three-phase Euler-Euler model, where one phase has zero velocity, and represents the porous zone. This makes things a bit easier, since you automatically have sum(vol. Fraction) = 1.

fluent_porous media_packed_bed

Hi Alberto,

Thanks for your reply. I've implemented 3 phase E-E model in Fluent, patching solid phase with constant packing factor 0.63 in the computational domain. But this 3 phase strategy is really computationally expensive and time consuming.

All I'm looking at is replacing the solid phase with "porous media" incorporating the suitable momentum sink terms in 2 phase E-E simulation. This saves time yet gives reasonable accuracy.

Any technical suggestion is more than welcome.

Regards,

SM

Quote:

Originally Posted by alberto (Post 288053)

I don't see why it is so much more computationally expensive of the two-phase simulation you have to run anyway, since you are not solving for the particle phase (it has constant zero velocity and constant volume fraction). The proper momentum sink is given by the drag coefficient, which should be based on the Ergun law for the phase pairs involving the porous zone.

Hi everyone,

I'm trying simulation porous media in rectangular channel, but the result isn't suitable with any research.

So, would you help me. I wish someone can check my simulation and give some reports if there is something wrong.

Thank you for your help.
Please send your e-mail, than i will send you my works to to your email.
my e-mail: oky.andytya.net@gmail.com

Regrads,
OKY Andytya P

note:
I use ANSYS Fluent 6.3 [CFD]

To: Dr. Alexander VAKHRUSHEV

I have been visited the website and make some contact. Theres is a problem with the address.

Would you like give your personal e-mail / website, because it's very helpfull. Tjanh you.

Regrads
Oky Andytya
oky.andytya.net@gmail.com

help in modeling compressible flow through porous media with heat transfer

Quote:

Originally Posted by hjasak (Post 192400)

Hi,

I have done a number of porous media flow model implementations, including scalar or tensorial resistance, using Darcy's law. They were typically a part of more complex model, like for example the biscuit baking model (mass transfer for air, liquid water and water vapour + heat transfer + stress analysis with large deformations) or similar complex heat/mass transfer models.

In these cases, the flow equations lose the momentum term and you can solve them just by solving for pressure. Currently, there's no top-level example code for porous media, because it's "too simple" and interesting only with some other phenomena.

Hrv

Hi Hrv,

I was looking for some help in modeling compressible flow in porous media, and to me you seem to be a senior member in this field. i would appreciate any help in this regard, if it does distract you from your schedule, I would understand,

In my problem I hava a vertical cylindrical domain and the complete domain is filled with porous media of porosity 0.6. Air inters to the domain at a velocity of 0.3 Mach no. and temp of 1000 degree centigrade, through 18 thin pipes mounted circumferentially at the side. and Air comes out from the top of the cylinder after passing through the porous media.

Actually I was facing problem in definig a porous zone on a tetrahedral mesh which I imported to discretize-setup as a *.stl import from star-CD mesh file. Also the imported mesh shows an extra patch "patch0", which has 0 face, and the rhoPorousSimpleFoam solver complains about this patch 0, and gives fatal error.

Please help me in getting some way to overcome this error. Also I would be grateful if you could suggest a solver for such kind of problems.

Regards,

MLD

Hi, everyone

How to get the value of convection coefficient [h] from Fluent directly ??

Regrads,

Oky

chemical reaction into porous media openfoam

Quote:

Originally Posted by arturo (Post 192403)

My main interest are chemical reactions and other physics on porous media, the so called packed bed reactors, so many other phenomena must be accounted for such as heat transfer, chemical reaction and mass transfer, its good to know that OpenFoam can tackle those cases.
Thanks for the answer and I hope I can post my questions if stucked.

Thanks to all

Arturo

hello, i'm new with openfoam and i'm using only the tutorials but for my preoblem i need a chemical reaction into a porous media so how can i do that like you did ?

Thank you in advance

Have you checked porousSimpleFoam?

yeah but there is not chemical reaction in porousSimpleFoam
how can i modify