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Active Member
CStrass
Posts: 9
Registered: ‎02-22-2013
Accepted Solution

Meshing issue? Solver exits unexpectedly

335 Views, 14 Replies
03-30-2013 09:57 PM

Hello, this seems similar to the post a couple below this one except that I'm not getting a nice visible little error code.  I started off having issues with the auto surface refinement taking forever to run.  So I decided to make a region around the area that I know will cause issues.  This caused an "out of memory" error upon surface smoothing.  Now I've added a second region located elsewhere on the model in an attempt to decrease the total number of elements.  Unfortunately, now it won't even get to surface smoothing before the solver crashes.

I've attempted to attach the cfz file, but I doubt it'll go through as it's 240MB.

 

Computer has 24 Gb of RAM and over 300Gb of free hard-drive space.

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Product Support
wildej
Posts: 755
Registered: ‎08-25-2011

Re: Meshing issue? Solver exits unexpectedly

04-01-2013 11:52 AM in reply to: CStrass

Hi,

 

Can I ask why you think a particular region will cause meshing issues? Have you considered fixing this in CAD rather than increasing the mesh count?



Jon Wilde
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Active Member
CStrass
Posts: 9
Registered: ‎02-22-2013

Re: Meshing issue? Solver exits unexpectedly

04-01-2013 05:38 PM in reply to: wildej

the total volume is 3m by 3m by 2m and I have a section that's 1.4m x 1.4m that has 6mm holes in it.  When I analysed this section on its own (previously) the gap refinement kept bugging me until I set the smallest possible element to 7e-8.  Even then there were still a few corners that didn't get meshed correctly.

 

This section can't be simplified because one of the 2 purposes of this analysis is to determine whether they do a good enough job at straightening the flow or not.

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Product Support
wildej
Posts: 755
Registered: ‎08-25-2011

Re: Meshing issue? Solver exits unexpectedly

04-02-2013 01:11 AM in reply to: CStrass

Hi,

 

This sort of model should be fine, so long as you are working within the memory confines of the machine. What is your estimated element count? You should be OK to mesh up to about 12-15m elements.

 

Are you using automatic meshing, with surface and gap refinement on?

 

We could take a look at the model if you can share a cfz. 



Jon Wilde
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Active Member
CStrass
Posts: 9
Registered: ‎02-22-2013

Re: Meshing issue? Solver exits unexpectedly

04-02-2013 07:31 PM in reply to: wildej

According to the automatic tools dialog box it's over 600 million elements.  I can't get the 2nd region to accept a value above 5 or so.

 

I began with automatic meshing.  Then I turned on surface refinement and waited 2 weeks.  It hadn't finished by the end of that so I canceled it and decided to set a region where I knew the issues would occur.  Then I added another region in an attempt to force some of the elements to maintain a larger size (and thus reduce total element count).

 

I'd like to share it but the cfz file is 240MB and this forum system doesn't seem to like files that large.

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Product Support
wildej
Posts: 755
Registered: ‎08-25-2011

Re: Meshing issue? Solver exits unexpectedly

04-03-2013 12:05 AM in reply to: CStrass

Wow, 2 weeks. You must be very patient!

 

Typically this should not take more than a few minutes, if it does, something is wrong.

 

How about I set up a Dropbox folder, happy to pm you a link, so that you can share the cfz.

 

Cheers,

Jon



Jon Wilde
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Active Member
CStrass
Posts: 9
Registered: ‎02-22-2013

Re: Meshing issue? Solver exits unexpectedly

04-03-2013 08:25 AM in reply to: wildej

A dropbox folder would be wonderful for this

 

Thanks

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Product Support
wildej
Posts: 755
Registered: ‎08-25-2011

Re: Meshing issue? Solver exits unexpectedly

04-03-2013 08:26 AM in reply to: CStrass

Hi,

 

I sent one over this morning :smileyhappy:



Jon Wilde
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Active Member
CStrass
Posts: 9
Registered: ‎02-22-2013

Re: Meshing issue? Solver exits unexpectedly

04-03-2013 08:28 AM in reply to: wildej

hm, then how do I get to the PMs?  (it hasn't sent stuff to my e-mail address in a long time)

 

 

Edit:

oops, typo.  Could you please re-send the link?  Sorry for the inconvenience.

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Product Support
wildej
Posts: 755
Registered: ‎08-25-2011

Re: Meshing issue? Solver exits unexpectedly

04-03-2013 08:33 AM in reply to: CStrass

Ah, I sent you an invite directly from Dropbox to your email, maybe check your junk email from this morning.

 

Please could you also share the native CAD geometry?

 

Thanks!

Jon



Jon Wilde
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