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MDB June 4, 2013 13:04

Assembling domains or blocks
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Dear Pointwise users,

I am a begginer user of Pointwise, and have been trying to sort out how it works on my own (version 16.04 is installed in my university's computers, but the user manual is not accessible, don't know why).
The good thing is that the geometry I'm trying to mesh is very simple, but several refinements are needed to accommodate the grid into RANS/LES turbulence models.

Capture1.png shows what I've been able to do: a 2D plane with the grid I would like to then extrude to obtain a 3D mesh.

I know how to create domains as I want them; from them I know how to create blocks (extruded...), but I don't know what to do afterwards: I end up with a bunch of blocks and domains which seem OK but they are not merged. Capture2.png is to show that the assemble option is not available. Assemble special is available but trying to use it I get empty blocks which cannot even be initialised (in Grid -> Solve).

What can I do in order to get a grid with the faces I need, highlighted in white in capture3.png and capture4.png, and all the cells as defined in capture1.png?

As a novel user I assume that I might have made many mistakes; any kind of reply would be helpful.

Naruto June 5, 2013 05:29

Dear MDB,
From your post it is not clear what you want to do afterwards. You can export blocks to your desired solver by selecting all the blocks and using export option. But before that you have to provide boundary and volume conditions.

MDB June 5, 2013 13:31

1 Attachment(s)
Dear Naruto,

First of all thank you for your reply.
My main problem is that I don't get how things are defined... Ideally I would like to have just a single domain in 2D, interior edges for walls of the cylinder and outer edges for inlet/outlet of the domain. On one hand trying to extrude all together, the assembly shows blue and pink colours whose meaning I don't know (see capture 1.png). On the other hand if domains are extruded one by one I have 7 interfacing blocks, therefore I have to set BC's on 22 boundaries (14 of them are set as front-back empty BC's).
Is that the usual procedure? Would that work properly on OpenFOAM instead of having just 1 front and 1 back face?

THanks again!

cnsidero June 5, 2013 22:35

This is a bit of a general reply but you seem to have some confusion about the the difference between the process of generating a mesh in Pointwise and exporting the mesh to your CAE solver (OpenFOAM in your case). I might suggest watching some of these videos:

If you still have some confusion after watching some of them, let me know your specific question.

Panboy June 6, 2013 10:31

I think it would be easier if you made a 3d sketch with connectors instead of a 2d and extruding.
Then you can set domains for all outer faces and the block will fill in everything inside. you might have to make domains on the inner surfaces as well to define biasing, but you won't need multiple inlets. I am not sure how Openfoam reads BC's though.

MDB June 8, 2013 12:19

Thanks a lot for your replies cnsidero and Panboy,

Finally my "problems" are solved. My confusion was that I thought a single block containing all grid points of the volume was needed, but thanks to cnsidero I saw that a mesh can be exported to CAE defined in many blocks.

Thank you again for your help.

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