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running out of memory importing an assembly

361 Views, 9 Replies
01/03/2018 8:51 PM

I am trying to load a inventor assembly into CFD. (This is the same file I have been designing with for a while now.) For some reason, when I try to update a design or make a new design with this IAM my memory starts to skyrocket until it runs out and cfd crashes. The assembly is not large (<400k mesh cells). each of the parts that make up the assembly can be loaded into cfd with no problem, but when I make them into an assembly it crashes (I tried multiple times). 

I exported an old version from CFD and re imported it. CFD did not crash, but I used about 80% to 90% of memory. So it seems that the most recent change (which was a slight increase in length of the fins) has cause the amount of memory to go beyond what my compute can handle.

 

Has anyone else had this problem and solved it? 

 

I'm using 

Inventor 2015

CFD 2018 

Windows 7 Professional 64 bit

64GB RAM


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Message 1 of 9 ( Views: 361 )

Re: running out of memory importing an assembly

01/04/2018 4:31 PM

Hello @PolsenAR,

 

This is an intersting issue you are having.

What is the total number of designs and scenarios you now have in the same file?

Did you try saving the assembly in a ACIS (*.sat) format and using that to update the design?  It is worth a try to see if it behaves differently.

 

Regards,

 

Marwan Azzam


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Message 2 of 9 ( Views: 332 )

Re: running out of memory importing an assembly

01/04/2018 5:39 PM

This will be the third design with one scenario each. (I like to start fresh after I start to get to many designs, so this is my second file) 

 

Yes I did, I tried .sat, .spt and .igs and the results were the same. 

 

Because of this I think that the problem isn't necessarily the file, it could be something in CFD. 

 

So I changed the model so that there would not be any automatic void filling on import. This seems to be a work around, I just have to do the Void fill command in the geometry tools after the assembly is imported. 

 

 


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Message 3 of 9 ( Views: 330 )

Re: running out of memory importing an assembly

01/04/2018 6:30 PM

@PolsenAR,

 

Interesting and smart approach. A while back I dealt with a heat sink model (maybe 100 channels, thousands of faces) which would stall for a long time (>8 hours) during the "creating internal volume" segment of a new Design launch. I didn't think of this earlier because it sounded like you were not even getting to the volume generation point.

 

For the issue mentioned above with the heat sink, the workaround was to just create the internal volume in CAD.

 

 

Best Regards,



Matt Bemis

Technical Support Specialist


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Message 4 of 9 ( Views: 327 )

Re: running out of memory importing an assembly

01/04/2018 9:02 PM

Well that must have been a fluke... The problem returns. It worked fine for that one time and now it doesn't work any more.

 

You are correct Matt I don't get past the "assembly model generated" text. 


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Message 5 of 9 ( Views: 321 )

Re: running out of memory importing an assembly

01/05/2018 4:30 PM

@PolsenAR Interesting.

 

 

Sorry to hear the issue came back. Would you be willing to share the CAD files with us? I'd like to test this on my machine and if appropriate log it was our development team.

 

Thanks,



Matt Bemis

Technical Support Specialist


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Message 6 of 9 ( Views: 306 )

Re: running out of memory importing an assembly

01/09/2018 6:30 PM

Sorry it took so long to respond...

 

I have attached an assembly with the parts that are causing the problem.  I have found out that the problem lies with the fins. If I shorten the fins by a couple of mils so they do not touch anything, The assembly loads very quickly with no problem. The only issue with that is the mesh count goes up and an hour simulation now takes a day. 

 

Let me know if you have the same issues on your machine. 

 

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Message 7 of 9 ( Views: 298 )

Re: running out of memory importing an assembly

01/16/2018 6:26 PM

Hello @PolsenAR,

 

The problem had to do with a slight interference as well as the way caps were made.  We used a boolean operation to remove the interference as well as made the caps separate parts.  It does us 10GB or so of RAM to open, but once the model is open it drops back down.

 

I am attaching a new zip file.

 

Regards,

 

Marwan Azzam

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Message 8 of 9 ( Views: 269 )

Re: running out of memory importing an assembly

01/23/2018 1:39 PM

Thank you, I finally had a chance to try it, and it worked. 


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Message 9 of 9 ( Views: 254 )