RBE3 in SOL103 Superelement model (Craig Bampton method)

Genius
Genius

Hello everybody,

 

I have to compute a superelement analysis with NX Nastran 10.0. I import different superelement in one single assemblyfem simulation and than perform all analysis.

In particular, to connect each superelement with RBE3 (not RBE2 because using this type of element introduce high stiffness near the spider!).

However I notice that the simulation "103 - Superelement" do not work and the simulation fail.

 

Can someone help me?

2 REPLIES 2

Re: RBE3 in superelement model

Phenom
Phenom

What do you mean by fail? What sort of meesage to oyu get?

I did some testing a while ago (purely as a profressinal interest!) with 1 SE and manage to get to work

Production: NX.CAE 10.0.2.6
Development: VB.NET (amateur level !)

Re: RBE3 in superelement model

Genius
Genius

Thanks for your answare.
I notice that the "Fixed boundary DOF" can not be applied direct to the central node of RBE3 elements. That cause the problem of resolution.

To overcome the problem I add an additional RBE2 element (with length = 0) attached to the center of my RBE3 spider.

Then, I use the free-end of additional RBE2 as DOF to apply the "Fixed bounday DOF". See the attached image.
Now work properly!

Image.PNG

 

 

Regards,

Alberto