No Thickness change for orthotropic/composite/fabric Materials in RADIOSS

Altair Forum User

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why i cant get any thickness variation in RADIOSS with composite/orthotropic/fabric shell property even if i make sure that ITHICK = 1 ?
shell thickness remains constant which is not physically correct 
Thank you in advance
H2

Altair Forum User

Hi H2,

When Ithick=2 the thickness is constant throughout the computation whereas for Ithick=1 true thickness is used during computation.

By default, shell thickness is supposed constant during shell deformation. Initial thickness is used to compute strains and to integrate stresses, but the thickness variation is still computed for post-processing reasons. If a variable thickness (Ithick =1) is used, true thickness is used for computation.

Altair Forum User

Hi George,

Thank you very much for the answer. But even if ITHICK=1 I just see a constant thickness over the whole calculation Time in hyperview . If I use /PROP/SHELL1 with ITHICK =1 I see a thickness variation over time . I m using MAT58 for fabric to simulate a draping process , thickness variation and material orientation are the primary results ? Do you have any hints to achieve that 

thank s a lot 

Altair Forum User

Hi,

Can you keep Ithick=2 and run the analysis. And  compare the results with Ithick=1.

If possible please share the model file so that we can review the same.

Altair Forum User

Hi George! 
Thanks for your reply, Here please take a look at this minimal Model. you can also switch between PROP16 and PROP1 easily 
Many Thanks
H2

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Altair Forum User

Hi,

For fabric materials you will not see the thickness variation. If you change the material you can see the thickness variation in the material.

 

 

 

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Altair Forum User

Hi,

1)
is that a limitation on the side of the Fabric-Material Implementation ? the problem here is that i cant use ELASTIC_MAT for modelling a fabric material. even if use an ORTHO_MAT i also cant see any Thickness variation.

2) 
about Drape Estimator function
can you Sir please explain to me how this process works? in the theory manual section there is nothing about it to read.
and how can i make a visual result from the Drape-Table ?

Thank you in Advance 
 

Altair Forum User

Hi,

1). I think this option is not available for composite materials.I will check regarding this and will update you.

 

2). Please find the material on drape estimator, which shows the application. Also please go through the Lightweight Design and Composites webinar at http://web2.altairhyperworks.com/hyperworks-13.0-webinar-series which is a session on composites and  HyperMesh drape estimator is also shown.

 

 

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Altair Forum User

Hi George !

Thank you for the information.
1- have you got some news about the fabric Material output ? is it  not possible to get thickness Variation using them ?
2- Drape Estimator i know how to use it, but i didnt understand how the process works in theory , since no Material-Card is needed to make a drape Estimation. do you know how the Process works in theory ?

Thanks again )
 

Altair Forum User

Hi,

For fabric/orthotropic thickness variation option is not available.

Drape estimation is done based on the thickness and orientation, no material info is required for the same. There is no much details available on drape estimator. I'll check internally for some materials and I'll share if I get some.