Code-Aster comm file for Hyper-Elastic Materials

Admin,

The Mooney-Rivlin hyper-elastic (nearly incompressible) matearial formulation IS available in Code-Aster and I have used it succesfully on 2D models. See examples SSNV187 & SSNV189.

y attempts at using it for 3D models seems to be at a pause at the moment. I am still trying.

Admin,

Mooney-Rivlin for nearly incompressible matearials IS available in Code-Aster. See verification problems SSNV187 & SSNV189. They are 2D examples, without contact.

Regards,
JMB

Hi there,

I've already posted this on the code-aster forum, apologies for the repeatition...

I've downloaded this software 2 weeks ago and since been trying to locate the ELAS_HYPER constitutive law for the mooney-rivlin behaviour. can any one tell me how to do that?

it doesn't appear in the DEFI_MATERIAU commands, nor under the STAT_NON_LINE command (COMP_INCR or COMP_ELAS); is it not available in CAElinux beta version (VMware).

I cannot find the docs, ssnv187 or ssnv189 for some reasons. does anybody have those?

it would be great if I could get some help in this area, whether someone can send me the files or let me know how to find them...

also is there a user group for user defined material? I'm quite interested in implementing laws for rubber material such as the 8-chain model. can we use strain-energy functions in Aster or enter new constitutive models (based on tensor calculus, invariants etc...) or can we only use the format implemented in INCLUDE_MATERIAU?


Thanks, Loe


JMB wrote:

I have just stumbled upon this wonderful software combination (Code-Aster + Salome) and am begining to learn it.

Has somebody used Code-Aster for the analysis of Hyper-Elastic Matrials? Since my knowledge of French is minimal (or poor) any help would be very much appreciated. I have trouble understanding some of the French documentation. If somebody could post an example of Non-Linear Stress Analysis of Hyper-Elastic Matrials that would be a big boon.

Thanks
JMB

Loe,

The French PDF files (V604187a.pdf & V604189a.pdf) are at the Code-Aster website, accessible after completing a registration process. I roughly translated the titles from the website as:

V604187a # SSNV187 – Validation of the law ELAS_HYPER on a cube
V604189a # SSNV189 – Validation of the law ELAS_HYPER on a strap

The .comm files are in /opt/aster/STA8.X/astest on my PC. I installed Code-Aster on RHFedora FC3 so I do not know about the CAELinux LiveCD route of installing Code-Aster. I presume it should be in the same (or similar) place.

If you want to integrate other laws in Code-Aster, it should be possible, since the source code is in the public domain. I have not done any coding myself, so I could not tell you how. Others may be able to help. If you do write additions to the code (Ogden, Arruda-Boyce, etc) I request that you make them available here so that others may benefit as well.

Enjoy,
JMB

Loe,

The French PDF files (V604187a.pdf & V604189a.pdf) are at the Code-Aster website, accessible after completing a registration process. I roughly translated the titles from the website as:

V604187a # SSNV187 – Validation of the law ELAS_HYPER on a cube
V604189a # SSNV189 – Validation of the law ELAS_HYPER on a strap

The .comm files are in /opt/aster/STA8.X/astest on my PC. I installed Code-Aster on RHFedora FC3 so I do not know about the CAELinux LiveCD route of installing Code-Aster. I presume it should be in the same (or similar) place.

If you want to integrate other laws in Code-Aster, it should be possible, since the source code is in the public domain. I have not done any coding myself, so I could not tell you how. Others may be able to help. If you do write additions to the code (Ogden, Arruda-Boyce, etc) I request that you make them available here so that others may benefit as well.

Enjoy,
JMB

Hi J,

Thanks for the reply...

Ive looked at that directory and it the validiation codes jump from SSNV186 to SSNV200 ie those files (187-189) are not there for some reason. I'm using version 8.2 so could that be the reason why?

the ELAS_HYPER doesn't show in efficas DEFI_MATERIAU or COMP_INCR/ELAS so maybe am using the old version? i'll look into the directory to try and locate where material properties are written, and implement a few rubber constitutive models it'll be great if some one sends me that source for ELAS_HYPER thou!

will first check if I can use the CALC_MATR_ELEM command to implement a constitutive model but I think it calculates this after solver (eg stat_non_line) rather than before...

Thanks, Loe