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Undefined value found // Hyperelastic parameters

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Here we go again: When it comes to solving im getting anther error wich is quite frustrating.
It says: Undefined value found. Detail: Undefined value found in. The equation-residial-vektor.
There are 51993 degrees of freedom provide NaN/Inf in vector for variable mod1.u.
(0.8225,0.0045,0.00555), (0.8225,0.0045,-0.001), (0.817488,0.0045,0.00555), (0.819994,0.0045,0.00555), (0.8225,-0.001,0.00555), ...
Feature: Stationary solver 1 (sol1/s1)

This continues for mod1.v and mod1.w as well.

Another thing wich i'd be interested in: Are there any typical parameters for silicone rubber hyper elastic model already in the internet somewhere? I got no material to make a new stress strain curve and calculate the parameters for Mooney-Rivin and so on ;)

Im looking forward to finally solve this someday ;)

THanks!

6 Replies Last Post 15.01.2015, 11:52 GMT-5
Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago 23.04.2013, 11:10 GMT-4
Hi Wolfgang,

Silicone rubbers have a wide range of stiffnesses. If you have experimental data you can post it here and I or others on the Forum may be able to calculate appropriate hyperelastic material constants for you.

Nagi Elabbasi
Veryst Engineering
Hi Wolfgang, Silicone rubbers have a wide range of stiffnesses. If you have experimental data you can post it here and I or others on the Forum may be able to calculate appropriate hyperelastic material constants for you. Nagi Elabbasi Veryst Engineering

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Posted: 1 decade ago 23.04.2013, 14:06 GMT-4
Actually i dont, i just wanted to take any typical rubber values for simulating silicone since i dont know wich element this is in the real case and i cant do a strain stress curve.

Actually i dont, i just wanted to take any typical rubber values for simulating silicone since i dont know wich element this is in the real case and i cant do a strain stress curve.

Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago 25.04.2013, 08:08 GMT-4
Here is a paper available online that has Ogden and Mooney-Rivlin constants for two silicone rubbers: www-mech.eng.cam.ac.uk/profiles/fleck/papers/191.pdf

Nagi Elabbasi
Veryst Engineering
Here is a paper available online that has Ogden and Mooney-Rivlin constants for two silicone rubbers: http://www-mech.eng.cam.ac.uk/profiles/fleck/papers/191.pdf Nagi Elabbasi Veryst Engineering

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 25.04.2013, 08:26 GMT-4
Hi Nagi

For some reason the link is not served from everywhere,
but I managed to find the file via Google using the following search code:

Ogden and Mooney-Rivlin constants silicone rubbers Fleck

Thanks I was also looking for interesting models/ values for my V&V of silicon rubbers

--
Good luck
Ivar
Hi Nagi For some reason the link is not served from everywhere, but I managed to find the file via Google using the following search code: Ogden and Mooney-Rivlin constants silicone rubbers Fleck Thanks I was also looking for interesting models/ values for my V&V of silicon rubbers -- Good luck Ivar

Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago 25.04.2013, 08:53 GMT-4
Thanks Ivar, the period at the end of the sentence was considered part of the hyperlink ... I fixed that so the link should work now.
Thanks Ivar, the period at the end of the sentence was considered part of the hyperlink ... I fixed that so the link should work now.

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Posted: 9 years ago 15.01.2015, 11:52 GMT-5
Hey,

As for the error, I once got similar one when started using hyperelastic interface. The reason for that was the default value for modulus in the interface was set to zero, which need to be changed to nonzero values. Hope this helps.

Hey, As for the error, I once got similar one when started using hyperelastic interface. The reason for that was the default value for modulus in the interface was set to zero, which need to be changed to nonzero values. Hope this helps.

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