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guillaume October 27, 2008 19:37

thin extrusion meshing
 
Hi I'd like to know your opinion on what is currently the best tool for meshing thin extrusions: I am modelling a double glazed window and its frame in 3D. The extrusion profile of the frame is fairly complex; it's made up of 2 mm thick aluminium. I'd like to mesh this profile anisotropic so that I don't end up with 10 billion cells. It becomes tricky with the fact that there are quite a few different materials in a window, and there are about 100 different interfaces between the different glass/frame materials and the air. The set up of all these interfaces is quite painful. Is there a tool around that could simplify the meshing process of this kind of geometry by offering reasonably anisotropic meshing techniques and automatic interface recognition? Thanks


Glenn Horrocks October 28, 2008 00:45

Re: thin extrusion meshing
 
Hi,

You will have to go to hex or sweep meshes for this geometry. Workbench is one option, ICEM hexa another, you can also look at the millions of other options (Gambit, Gridgen etc etc).

If you already have Workbench I would give that a go first. Interfaces can be set up in WB or automatically found on import to CFX-Pre. No guarantees on the accuracy of the automatic grid recognition in CFX-Pre however, you will have to test that.

Glenn Horrocks

guillaume October 28, 2008 00:53

Re: thin extrusion meshing
 
Glenn,

I used cfx a few years ago, but I am a bit rusty on it and not uptodate. You mentioned that CFX pre can recognise interfaces automaticaly. What's the process to create the mesh then? Do you need to go back into the CFX mesher once you've created the interfaces(in CFX pre)by exporting in some way or can you keep working and extruded mesh in CFX pre? Thanks

CycLone October 28, 2008 08:55

Re: thin extrusion meshing
 
If you group the bodies into a single part in DM, the sweep method will automatically match the nodes at the interfaces, so there will be no need for GGI connections. CFX-Pre will insert an automatic interface between the solid and fluid bodies when you create the domains.

If the bodies are not grouped into a part, the meshes may not match (though the surfaces still will). In that case Pre will determine contact between the bodes and insert an automatic interface to account for the contact. As you create your solid and fluid bodies, Pre will update the automatic contact regions to suit the appropriate physics (i.e. fluid-fluid, fluid-solid, solid-solid). You can also create the contact manually.

-CycLone

Rogerio Fernandes Brito October 28, 2008 21:09

Re: thin extrusion meshing
 
U can use Extrude tool inside the icem cfd. make a 2d mesh (hexahedrical mesh, i mean) and extrude the mesh. U can choose the number of layers and the thickness of each one.

Rogerio Fernandes Brito October 28, 2008 21:10

Re: thin extrusion meshing
 
#U can use Extrude tool inside the icem cfd. make a 2d mesh (hexahedrical mesh, i mean) and extrude the mesh. U can choose the number of layers and the thickness of each one.#

guillaume October 28, 2008 22:28

Re: thin extrusion meshing
 
Rogerio How difficult is it to create interfaces between bodies in ICEM?

Rogerio Fernandes Brito October 29, 2008 06:39

Re: thin extrusion meshing
 
Hi Sir Guillaume,

Untill nowadays, im still learning about it. One day, i will make a movie (name.AVI) with SnagIt 7 software ( http://www.4shared.com/dir/8616671/d...Downloads.html ) and i will send it to rapidshare. I think its easier to explain than typing in here. Wait please.


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