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j_p July 22, 2011 11:27

Creating a boundary condition within a face (ANSYS Workbench/Fluent)
Hi all

I'm new to CFD so apologies for the simple question.

I have a regime where there is a certain area of a face (i.e. not the whole face) which needs a velocity inlet.

I'm using workbench for generating the geometry and mesh, then FLUENT for the CFD analysis.

Using the geometry tool within workbench, I've managed to draw a 2D sketch on a face, it's just a problem when the geometry is imported into FLUENT and the meshed sketch isn't picked up to be selected as a BC inlet.

Thanks in advance for the help, I'm sure this is a basic question for someone who knows...!

J_P :)

PSYMN July 23, 2011 13:46

The secret to bocos in WB is "Named Selections"...

However, you will first need to use the sketch to cut out the face so you can select it... I forget how to do that off the top of my head, but you can look into the DM help for that. (or maybe someone else reading this can give that detail).

Andrew.Coughtrie July 24, 2011 15:49

What you'll be wanting to do from the sounds of things is to imprint your sketch on to the face. You do this by extruding your sketch and selecting imprint faces from the operation box, the solid you're imprinting into must be a none frozen solid for this option to be available. You can then select this face to create a named selection from it. Imprinting doesn't actually do anything to the geometry apart from give you a face to select and use elsewhere.

Hope this helps


j_p July 25, 2011 11:57

Thank you for your help guys, I'll try the suggestions :)

j_p July 28, 2011 11:16

Yep, extrude, select imprint, then named sections works fine. Many thanks

Tanjina July 3, 2013 14:06

Model information is incompatible with upcoming mesh
2 Attachment(s)
Hi all,

I got the problem described in this thread. Following the instruction described in this thread, I solved the problem. But Now I am facing new problem. After naming the all the edge I want, when I try to open fluent, it says me "model information is incompatible with upcoming mesh" and it says that it can;t found some zone. Please see the attached image. Thanks all.

PSYMN July 5, 2013 16:30

I think this only happens when you setup a model (say you applied a velocity inlet at INLET1) and then your new mesh is missing something you referred to in the previous setup (there is no INLET1).

You can fix the mesh, or proceed with the setup on the new mesh.

Tanjina July 8, 2013 00:15


I understand what are you trying to say, I faced similar problem before. But this time, I think this is not the case. Because no matter what I changed ( even I reset mesh sometimes) it always says that It can't find "surface zone ".

Is it something like that I have to create surface in two sides of the line which is lied within the rectangle ?

PSYMN July 8, 2013 09:44

I still think it is saying that "interior-surface_body.1" and "wall-surface_body" are used in the setup or post, but not included in the mesh you are currently providing. You must have had them in the initial mesh. Perhaps they were default names that you have since changed.

This is just a warning. Check your boundary conditions, post, etc. and if it all looks correct to you, try to solve it.

Tanjina July 8, 2013 11:39

1 Attachment(s)
Hi Psymn,

Thank you. You were right. Now it's working. But didn't give the expected result.

I have some queries. It will be very helpful if you can suggest any way. I want to model very simple geometry. a submerged porous pipe under water. For doing so, Upper portion is filled with water and lower portion is filled with air. In between these two portion I want to assign a porous medium so that water can come to lower portion through the porous media. for that

1) I assign a BC in between two portion which is porous jump. ( I don't know how can I assign porous media except this way)
2) I remained all default value except the thickness . I assigned thickness 0.1 m
3) What value should I assign as face permeability ? I just used the default value 1e10 which seems very large to me .

Please see the attached image. No changes take place .


Tanjina July 8, 2013 12:34

Porous pipe
1 Attachment(s)
After 350 run, it looks like the attached image. But it should be falling on by droplet, no If I am not wrong ?

Could anyone please tell me what should I modify ?

PSYMN July 8, 2013 14:13

I am only replying because you called me out, hopefully someone else can actually help.

Not sure about what settings you should use...

Also, I have only ever used volume regions with porous media, not zero thickness boundaries with assigned thickness.

Tanjina July 8, 2013 14:34

Thank you . :)

Could you please refer me any post where I can find steps of modeling of porous media in workbench? And could you please tell me which one is better for modelling of porous media, workbench or ICEM? I never used ICEM.

PSYMN July 8, 2013 16:17

To search CFD Online, I usually use a site specific search thru Google. I find it works much better than the CFD-Online built in search.

As for the setup, it doesn't matter which tool you use. Setting up a porous media in the solver is pretty much the same. The solver just needs to provide a boundary or zone for you to select, and they all do that.

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