Hyperelastic Inputs

[SuttonA]

I am working on evaluating if FeMap would be a useful tool for the design engineers for doing quick FEA on their own. A majority of our work involves rubber and silicone, which results in having to use hyperelstic models. The typical format that FEA annalist are used to is inputting materiel properties is using either the Mooney–Rivlin or Neo-Hookean constants for Abaqus. However, the hyperelastic inputs for FeMap look to be the modulus matrix. I have spent some time searching for a correlation between the rubber models and the "distortional deformation constants (Aij)" but have not been able to find anything. I have also searched for any examples for FeMap rubber models but, only turned up the tie rod model. And that only gives me 2 parts of the matrix without an explanation. Does anyone have tutorials or info on what to use for inputs for hyperelastic materials?

Thanks,
Andrew

 

[gfbotha]

Hallo Andrew

I do not want to unnecessarily cross-post; do you perhaps have access to Siemens GTAC support forum "Femap Misc"? - because there I recently responded to a similar question offering a simplified approach you might like to consider. Say if you do not get right.

You might like to have a look at some relevant discussions under "Finite Element Analysis Engineering" forum - here on EngTips. Then the theory manuals of the more prominent FEA codes also cover the theory to some extent (but granted, not always the complete details of the various proper test options).

Regards