[theshard]

How do I make a geometry for a porous media and then mesh it? What softwares can I use?

[ashokac7]

Originally Posted by theshard

How do I make a geometry for a porous media and then mesh it? What softwares can I use?

You can do this in any CFD software like Fluent or Star-CCM+ etc. For the geometry you only have to extract outside surfaces. Create a separate region where porous medium is there. We assign it a porous media and give Inertial and Viscous coefficient values.

P.S. Try reading some papers and then ask more appropriate question.

[theshard]

I'm trying to construct the internal geometry of the membrane/porous media itself. I know that you can create a porous media using the method you mentioned but that is not my question.

Originally Posted by ashokac7

You can do this in any CFD software like Fluent or Star-CCM+ etc. For the geometry you only have to extract outside surfaces. Create a separate region where porous medium is there. We assign it a porous media and give Inertial and Viscous coefficient values.

P.S. Try reading some papers and then ask more appropriate question.

[lcarasik]

Originally Posted by theshard

I'm trying to construct the internal geometry of the membrane/porous media itself. I know that you can create a porous media using the method you mentioned but that is not my question.

Like ashokac7 stated, Star-CCM+, ANSYS FLUENT, ANSYS CFX, OpenFOAM, others can model this program. This is a very generic CFD problem (you can use a unit cell representation).

[ashokac7]

Originally Posted by theshard

I'm trying to construct the internal geometry of the membrane/porous media itself. I know that you can create a porous media using the method you mentioned but that is not my question.

This is really your choice though. Like if only pressure drop is concerned to you it is not advisable to model the whole porous structure. Porous approach is sufficient for that. But if you want to model each and every layer/membrane in porous media, that's tricky. Think in terms of resource you need for that. Like between two adjacent layers, we have to put atleast 4-5 layers in between so that CFD have some domain to make calculations there. This is also on the top of refinement we have to do to capture exact surface feature which also increase the mesh count exponentially. And this is why porous coefficient approach come to existence, isn't it?

[theshard]

I'm trying to work with many factors including pressure drop. I have the pore diameter, length of pores, number of pores in given area and thickness of membrane. I'm encountering a problem when I construct the geometry because the diameter of the pore is in nanometre (1.8 nm) and the area is in mm(0.8mm*0.8mm). I tried working this out in Catia but in vain. Even if if do model it in these dimensions, I guess it will pose meshing problems?
I want to know how to approach this situation.

[ashokac7]

Originally Posted by theshard

I'm trying to work with many factors including pressure drop. I have the pore diameter, length of pores, number of pores in given area and thickness of membrane. I'm encountering a problem when I construct the geometry because the diameter of the pore is in nanometre (1.8 nm) and the area is in mm(0.8mm*0.8mm). I tried working this out in Catia but in vain. Even if if do model it in these dimensions, I guess it will pose meshing problems?
I want to know how to approach this situation.

Clearly you can not easily model such problem as it is in CFD. Diameter is too small. Instead try to calculate the porous coefficients for your case. refer this https://en.wikipedia.org/wiki/Fluid_...h_porous_media

Darcy's law is there to deal with these cases.Even if you are able to create the geometry in Catia how will you model it here. The factors you have maintained will be taken care by porous coefficients.