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-   -   Gridgen Cobalt 3D Export Issue (http://www.cfd-online.com/Forums/pointwise/79749-gridgen-cobalt-3d-export-issue.html)

AeroCat September 2, 2010 11:54

Gridgen Cobalt 3D Export Issue
 
I have used Gridgen's Anisotropic feature for the first time to build an unstructured grid around an aircraft. The total cell count is roughly 15 million.

I set the BC's, and when I try to export the analysis data I get a face allocation error. I realize that Gridgen is limited in memory usage with 32 byte and all.

Pointwise suggested I import the grid into Pointwise since it is 64 byte. When I try to do this, it stops and hangs at 78% when reading the .gg file.

Anyone have any advice? I'm running on a Dell workstation with 48 Gb of RAM running Vista.

carodear September 3, 2010 12:22

Quote:

Originally Posted by AeroCat (Post 273771)
I have used Gridgen's Anisotropic feature for the first time to build an unstructured grid around an aircraft. The total cell count is roughly 15 million.

I set the BC's, and when I try to export the analysis data I get a face allocation error. I realize that Gridgen is limited in memory usage with 32 byte and all.

Pointwise suggested I import the grid into Pointwise since it is 64 byte. When I try to do this, it stops and hangs at 78% when reading the .gg file.

Anyone have any advice? I'm running on a Dell workstation with 48 Gb of RAM running Vista.

Hi AeroCat,

I should be able to help you. Do you mind answering a couple of questions first?

What versions of Gridgen and Pointwise are you using currently?

Do you have a Linux workstation available? A 64-bit version of Gridgen is available for Linux platforms. If you have one, this is an easy way to get around the memory limitation.

For the grid you generated, how many blocks does it contain?

AeroCat September 5, 2010 19:44

Hi Carolyn,

I uploaded my grid so that George could take a look. Haven't heard back from him yet. He was the one suggesting that I export the grid and then import it in Pointwise. When I went to import into Pointwise, it got stuck on me.

We have the latest version of Gridgen. Whenever we get the notice that a new version is out we update it.

No access to a Linux workstation.

One block. I realize that is probably part of what is giving me fits, but there really wasn't any need to break it up into smaller blocks. I guess I could try to turn on the MaxBlockSize thing on the unstructured solver and limit my block size. Any recommendations on what size?

carodear September 7, 2010 10:20

Hi AeroCat,

Last week we just released Gridgen V15.16 and Pointwise V16.03 R4. You may not have had time to try these versions yet.

Both versions contain a good number of bug fixes that I think could help your situation. Could you double-check to see if they've been installed yet and let me know?

Also, what solver are you exporting to? Each solver's export routine is a little different and some use a bit more memory than others to get a grid out.

Thanks!


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