No Beam Stresses

Haben Sie einen Fehler in Z88Aurora entdeckt? Dann helfen Sie mit und sagen es uns! /
You have discovered an error in Z88Aurora? Tell us the horrible truth!

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Inquisitor
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Registriert: Fr 7. Sep 2012, 00:14
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No Beam Stresses

Beitrag von Inquisitor »

I’m working with 3D Beams (2) and I see the stresses in the z88o3.txt file, but when I am in the Post Processor and select “Stresses per element”, I get “No results available!”

Is this a bug or do I have something mis-configured?

Thanks.

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auroraIco
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Re: No Beam Stresses

Beitrag von auroraIco »

Hlelo Inquisitor,
it´s not a bug, it´s a feature. :D
Please see theory manual, p.123:
"What can I plot? Nearly everything if a solver was run which stored the deflection file Z88O2.TXT and the three stress files Z88O3.TXT (for you to check the stresses), Z88O5.TXT (for Z88O internally) and Z88O8.TXT (for Z88Aurora internally). Even for trusses you may plot the "von Mises“ stresses (i.e. tensile stresses) with different colours; only beams No.2 and No.13 and cams No.5 allow only the plotting of deflections and nothing more. Why? Because you must compute for beams and cams also the stress concentration factor which is impossible for a FEA system which deals with a whole structure of beams. Of course, you may compute the stresses in a chamfer by putting an FE mesh around it. But this needs either plane stress elements or 3D elements but neither beam elements nor cam elements. "

Greetings, Aurora_ico

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Inquisitor
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Re: No Beam Stresses

Beitrag von Inquisitor »

aurora_ico hat geschrieben:Hlelo Inquisitor,
it´s not a bug, it´s a feature. :D
Greetings, Aurora_ico
I love it! :lol: We use that one here at my day job all the time!
Sorry, I thought I had digested the manuals. I must have killed the brain cell while watching the football game.

I can live with, but...

All finite elements are approximations and don't show actual stresses around any stress gradient. Until exact geometry is model, more refinement makes the stresses go up... unless you have a say... a crack tip element. The current graphical output even "blurs" the results by showing gradients across elements that may or may not exist. So for my needs, "just" pin-pointing a high region graphically within a model is merely a convenience so I know where to do a more detail model with shells or solids.

Thank you responding.
Zuletzt geändert von Inquisitor am Di 18. Sep 2012, 11:48, insgesamt 1-mal geändert.

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auroraIco
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Re: No Beam Stresses

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You are welcome.

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