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#1 2020-09-04 04:31:15

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Non Convergence from shell to shell contact

Good day all,

Im having a problem with the convergence of contact by using shell element (COQUE 3D), It always diverge at 45% load.

Ive tried penalization method, but the result are much worst (failed at 1%)

Please feel free to comment and correct me.

Attached are the comm file and med file.


Thank you very much.


Warmest Regards,
cwf007.


Attachments:
Contact_testing.zip, Size: 14.33 KiB, Downloads: 20

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#2 2020-09-07 15:44:17

mf
Member
Registered: 2019-06-18
Posts: 117

Re: Non Convergence from shell to shell contact

Hi,

I was curious to investigate your problem, I ran your files. The problem is: it already stops at AFFE_CHAR_MECA. So it does not reflect what you describe.

As your problem might be mesh related, could you upload your .hdf?

Thank you,

Mario.

P.S.: your mesh file does not have the groups addressed in AFFE_CHAR_MECA, that's what the error says.

Last edited by mf (2020-09-07 15:45:42)


Attachments:
message, Size: 31.85 KiB, Downloads: 18

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#3 2020-09-08 02:29:00

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Re: Non Convergence from shell to shell contact

Hi Mario,

Really appreciate your time.

Attached is the .hdf.

Thank you.


Warmest Regards,
cwf007.


Attachments:
Study1.hdf, Size: 470.12 KiB, Downloads: 20

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#4 2020-09-08 07:05:20

konyaro
Member
From: Genève
Registered: 2016-04-02
Posts: 249

Re: Non Convergence from shell to shell contact

Hello,
I'm not used to shell elements but re-orienting the contact surfaces leads to convergence. I also modified the contact in order to make it faster.

Konyaro


Attachments:
shell_ctc.zip, Size: 20.1 KiB, Downloads: 21

失敗は成功のもと (L'échec est la base de la réussite)

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#5 2020-09-08 10:48:20

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Re: Non Convergence from shell to shell contact

Hi Konyaro,

Thanks for helping out!!

Such a huge mistakes I've made!

May i know how do we really define the E_N on penalisation?

Thank you!

Warmest Regards,
cwf007.

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#6 2020-09-22 03:25:57

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Re: Non Convergence from shell to shell contact

Dear all,

After switching to a slightly complex geometry, (denter and a panel) with VMIS_ISO_TRAC , Im getting non convergence at 30%

Feel free to comment on my model.

Attached is the hdf file.

Thank you smile


Warmest Regards,
cwf007

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#7 2020-09-22 03:29:03

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Re: Non Convergence from shell to shell contact

Reattached the hdf file.

TQVM smile


Attachments:
Study1_denter2shell.rar, Size: 509.34 KiB, Downloads: 13

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#8 2020-09-23 08:49:23

marco.mueller
Member
Registered: 2020-01-16
Posts: 24

Re: Non Convergence from shell to shell contact

For my shell models, I've had quite good results with ALGO_CONT='PENALISATION' - also regarding run times!
If it fails, try to decrease E_N (For steel-steel, I've used Young's Modulus/100).
E_N may be too low, if you get contact penetration.

Last edited by marco.mueller (2020-09-23 08:49:40)

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#9 2020-09-24 02:08:40

cwf007
Member
From: Malaysia
Registered: 2020-06-05
Posts: 13

Re: Non Convergence from shell to shell contact

Hi Marco,

Definitely will try to reduce E_N

Thanks for the tips!

Warmest Regards,
cwf007.

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