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[zjuv9021]

Hi all,

In doing FEA analysis with elastomers, I've read a good deal of tips and tricks in regards on how to approach to improve convergence:

 

https://caeai.com/blog/tips-tricks-fea-modeling-rubber-and-elastomers-part-2

https://caeai.com/blog/dealing-incompressibility

 

Most of these have common themes, including implementing Selective reduced integration (B-Bar), Mixed Formulations, Mixed u-P formulations, enhanced strain formulations, adjusts to volume compatibility constraint, etc.. I've heard things as shear locking and volumetric locking being an issue of concern as well with these types of materials.

I'm not quite familiar with how to actually implement these kinds of techniques within ANSYS mechanical. I am aware of Commands via APDL that can be attached to the Geometries, is this where I could implement some of these above methods to attempt to aid in convergence?  Could someone please provide me an example of how to introduce some stability and practical methods as above within my ANSYS to help get more towards convergence, generally speaking?

Thank you!

[peteroznewman]

Here is a post with some of those settings that help elements support the large strains that will be developed in hyperelastic material models.

[zjuv9021]

Peter - It doesn't appear that 19.2 has the element control and brick intergration scheme options. Any thoughts on how to do this?

Regards,

Zach 

[Sandeep Medikonda]

Zach,

  Mechanical will try to make the best guess for the based on the element selected to mesh and the material you are using.

  You can change the element formulation by changing the key options. So, for something like Solid 185, this is KEYOPT(2) and B-bar is the default for this element type.

Regards,
Sandeep
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