Non converge solution for contact problem

Kouider

Dear All,

 

Iam trying to perform a 3point bending test for Composite. and for that i have creat an indentor and a Composite plate with contact between both as can be seen from the Image. however, iam getting a converence Problem while process the Analysis via optistruct. i have attached include this request the fem and the out files for my model. can you please help solving this issue

 

Kind regards 

 

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Adriano A. Koga

Maybe you need to refine the mesh a little bit more to get a better contact distribution. And also to get a better response in the most critical areas for bending.

 

Another thing that I would suggest is to change force by enforced displacement, as it is usually easy to converge.

Kouider

Thank you for the Reply 

 

I have already did that, but unfortunitly the same Problem accured 

Adriano A. Koga

you mean you did both tests?

 

By the way, you should take care with penetrations in your contacts.

As you can see, if you consider both shell thicknesses, your model has some penetrations which will generate large contact forces as stated by the nl.out file.

With these penetrations, the solver will try to push back your part.

 

Also, your BCs are only constraining DOF 3. I believe this is not properly set, as your model is free to move in XY plane. Also your impactor should be constrained at some DOFs to make it easier to converge.

 

--------------------------------------------------------------------------------
        MAX PENETRATION ERROR       0.2225907396D+01      AT NODE       298      CONTACT INTERFACE group1 (Slave,Master)
        MAX PRESSURE ERROR          0.3680652217D+06      AT NODE       298      CONTACT INTERFACE group1 (Slave,Master)

<?xml version="1.0" encoding="UTF-8"?>

FaroukM

Altair Forum User said:

Dear All,

 

Iam trying to perform a 3point bending test for Composite. and for that i have creat an indentor and a Composite plate with contact between both as can be seen from the Image. however, iam getting a converence Problem while process the Analysis via optistruct. i have attached include this request the fem and the out files for my model. can you please help solving this issue

 

Kind regards 

 

<?xml version="1.0" encoding="UTF-8"?>

Hi Kouider,

 

Try to refine the mesh for the slave surface. I recommend also to use regular finite element.

 

Cheers,

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Kouider

Thank you for all your valuable comments..

the Problem was that i didnt define any constrains for the indentor. 

 

Kouider