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Stabilize contact calculation in Sol 101 to reduce calculation time

Hi guys,

 

I set up a model using contact in Sol 101. So far everything is working fine. The calculation is finished after approximetally 10 min.

 

Unfortunately my model is consiting of a high number of subcases (105). Therefore you can imagine it takes a lot of time to calculate the whole solution including the subcases considering the contact definitions.

 

My question is now, does anybody has an idea how to stabilize the contacts to safe some time during calculation. Reducing the calculation time of one subcase from 10 to 9 minutes would safe already almost 2 hours for one single model.

 

I alreay tried to split the contact face into several smaller faces.

 

The contacts are between 3 cylindrical coincident faces with a gap in between because bearing are missing. So I use the offset option to consider this.

 

Thanks

 

Georg

2 REPLIES
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Accepted by topic author GStrickner
‎08-26-2015 04:32 AM

Re: Stabilize contact calculation in Sol 101 to reduce calculation time

Dear Georg,

The best recommendation I can tell you is to use exactly the same mesh (ie, matching mesh) in both source & target regions to avoid interferences (initial penetrations) between contacting meshes (see my post here http://iberisa.wordpress.com/2012/01/14/mejora-de-resultados-de-contacto-lineal-con-inipene-en-femap...

 



This is possible when using mapped mesh with CHEXA 3-D solid elements or 2-D mesh with CQUAD4 elements. Here the benefics are inmediate, faster convergence, best quality of vonMises stress results, not hot spots, and very important: reduced model size!!.


If HEX/QUAD meshing not possible, only TET10 meshing available, then very important to make sure to move midside nodes to the surface, this way you will avoid initial penetrations between contacting mesh on regions source/target.



Another good recommendation when defining contact regions and pairs on geometry which is not tangent continuous, creating single contact regions which cross corner transitions can result in non-uniform stress results around the corners. It is recommended to break these areas into multiple regions and define pairs accordingly.

Also when defining contact regions and pairs, it is recommended to not include the same element face in multiple regions. Repeating element faces multiple times in the same or different regions can significantly increase memory requirements and degrade performance.

And finally, avoid creation of regions either source or taget with "island" surfaces: all faces should be continuous!!.

To learn more take a look to my post:
http://iberisa.wordpress.com/2012/01/16/tratado-completo-sobre-como-resolver-problemas-lineales-de-z...

Best regards,
Blas.

Blas Molero Hidalgo, Ingeniero Industrial, Director
IBERISA • 48004 BILBAO (SPAIN)
WEB: http://www.iberisa.com
Blog Femap-NX Nastran: http://iberisa.wordpress.com/

Re: Stabilize contact calculation in Sol 101 to reduce calculation time

Hello Blas,

thank you for your answer. After some attempts I managed tor reduce the calculation to 3 to 4 minutes.

Regards,
Georg