NEi Contact between 3 shells

[danohl]

Hi,
I have a model that consists of shell elements (mixed composite and steel plates, extracted from outer/mid surfaces). At some locations I have overlaps of as much as three plates (at some locations the outer surface is a solid).

Now, I want to model contact between these and I'm trying to get NEi contact working but of course the middle plate can only have one normal direction, I guess the normal directions need to point towards each other but obviously that's a problem when I have three plates...

Do I need to model the mid layer as solid or maybe as two glued together t/2 shells to get two normal directions from this layer, or is there an easier way around this problem? I have used the NX nastran linear contact in the same model and it seemed to work what I've seen so far, but I can't get the NEi contacts to work.

Thanks,
Daniel

 

[kalinka]

With Femap covering pre- and postprocessing for NEi Nastran, what to do when you’re creating contact segments is first pick the front faces for one side of the contact and then the back faces for the other side of the contact. This reverses the node order on the BSSEG for the back side of the plates such that the contact points correctly.