how to define contact in axisymmetric model

[engineerbe]

cross-section of a revolved structure, modelled with 2D axisymmetric parabolic elements.
There is a gap between the two parts. Model is in global XZ plane, gap between parts is oriented in vertical direction so contact should be found in x direction.
I've tried slide lines and gap elements within an advanced non-linear analysis, but nothing seems to work, the faces penetrate without any reaction.

can anyone give me some tips?

 

[engineerbe]

It feels like I'm a pioneer on this subject, seen the reactions so far (0). Any reaction is welcome...

 

[namklof]

Did you provide a compression stiffness value in the gap element property table? In Advanced nonlinear, it works as a nonlinear spring and needs the user to provide appropriate tension and compression stiffness values.

 

[engineerbe]

The problem lies in a sort of bug in Femap. Below I summed all information.

Thank you Namklof for your reaction. I knew about the springs but needed real contact element.
-----------
Siemens made a Problem report that will be solved soon (high priority):

FEMAP is incorrectly writing out the slide line contact for a 601 solution. The Nastran 7.0 QRG, page 1009, Remarks related to SOL 601, remark 6, says that contact for SOL 601 is defined using a BCTSET entry instead of the BCONP entry. The deck written by FEMAP 10.1.1 is lacking this entry.

As a work around the user may do the following:

Add this line to the bottom of the case control section, just before the begin bulk line:
BCSET = 100
Then add this line at the very bottom of the file just before the ENDDATA line:
BCTSET,100,2,1
This can be done via the edit preview functionality.

 

[trainguy]

It cracks me up that for "legacy" reasons, Femap and/or Nastran are using 70's terms like "deck" to refer to a line in an FE input file!

It's 2010 people. Time to progress.

tg