axisymmetric elements in radioss bulk

Altair Forum User

Hello,

 

    I was seeking for axisymmetric element in Radioss Bulk and i was surprised hyperwork 11 do not have it. I saw in the tutorials there is a way to do it with hexa 3D elements but there is no axisymmetric elements like CQuadX in Nastran. Did i miss something?

 

Thank you,

Altair Forum User

Hello,

 

if i understand it correct, the MSC/Nastran CQUADX element is only for fully nonlinear (i.e.,large strain and large rotations) analysis available.

 

MSC/Nastran 2012 Manual:

CQUADX - Fully Nonlinear Axisymmetric Element

Defines an axisymmetric quadrilateral element with up to nine grid points for use in fully nonlinear (i.e., large strain and large rotations) analysis.

 

Sounds like a 'MARC' only element, not really bulk.

 

 

In Radioss you have the CTRIAX6 or CTAXI elements. For more informations look at the solver manual...

 

CTRIAX6

Bulk Data Entry

CTRIAX6 – Axisymmetric Triangular Element Connection

Description

Defines an axisymmetric triangular cross-section ring element for use in linear analysis.

 

 

Regards,

Mario

Altair Forum User

Right, i used CquadX just for the exemple. It seems that CquadX can work for linear analysis in Nastran too. But actually it's not the question.

 

It seems that CTRIAX6 or CTAXI elements are only available with hyperworks 12 (i'm actually working on hw 11). Then i assume i cant do this in that way.

 

Thank you for the answer.

Regards,

Altair Forum User

Hello, guys,
 
I noticed that too. I am familiar with axi-symmetric problems because I did some using Abaqus, and I was surprised and little dispointed that no such elements or examples could be found in radioss.

In the tutorials there is one 'RD-1070: Analysis of an Axi-symmetric Structure using RADIOSS' but actually it also uses 3D element rather than 2D axi-symmetric element.

 

In HyperWorks 12 we can find something on CTRIAX6 and CTAXI but still no tutorial about that. Nor can I find those two types of element from HyperMesh - 2D - elem types. Do I have to set it to CTRIA3 or CTRIA6 then edit it in fem file?

 

I hope there are some updates about this in HyperWork 13.

 

 

Dean Han

Rahul_P1

Dean, All

 

Yes, As a workaround, you will need to assign ctria6 elements and then edit the deck and 'replace string' ctria6 to ctriax6 this option is available in most test editors

 

You also need to make sure the 3rd field refers to material Id and not property Id. 

 

HM will start supporting these elements in the future versions/releases/updates