Learning Forum

[pdsamuel]

Hello, I have been trying to use tiebreak contact (CONTACT_AUTOMATIC_ONE_WAY_SURFACE_TOSURFACE_TIEBREAK) [Option 9] with the 20 noded Hexahedral solid element (ELFORM 23). When I select the surfaces using the segment set approach- it keeps giving me an error that certain master, slave surfaces have not been not found. Because this didn't work, I then tried defining tiebreak contact using the PARTIDs. But, with this approach the nodes on the middle of the edges don't get selected and only the nodes on the corners are tied. I strongly prefer to use the segment set selection of tiebreak surfaces, and need to know to how to execute this for the 20 noded hexahedral elements.

Also another associated issue is that when I use a regular a contact definition between two hex elements and apply a closing/compressive load, there is interpenetration at the middle nodes (i.e. the nodes in the middle of the edge)- which should not occur.

Can anyone share from LSDYNA support/community help figure a solution to these problems? Thanks

[Reno Genest]

Hello,

Which version of LS-DYNA are you using? Could you post images showing the problem?

 

Reno.

[pdsamuel]

The problem that occurs when using PART ID definition of the tiebreak contact- All the nodes of the element are not being tied (only the corner nodes).

 

[pdsamuel]

The error message that shows up when using segement set ID for definition of tiebreak contact. It is not able to detect the element now. 

[Reno Genest]

Hello,

Could you send your test model to your Ansys account manager? He will forward it to me and I will have a look.

Thanks,

 

Reno.