Unpicking edges from contact definitions

[satyasrinivas]

Hi,

I am trying to define contacts in Abaqus, but I am running into a problem.
I want to define a slave surface which is composed of a surface 'minus' the nodes along a selected edge of that surface. Is there a way to do this in CAE ?

I tried unpicking the edges using 'ctrl' button in CAE. But for some reason, the display shows that all the edge nodes are still included in the contact definition.

Any suggestions ?

Thanks
SS

 

[corus]

I suspect that as you need a surface then as a surface has edges, so you can't unpick them.

corus

 

[DanStro]

Can you just partition the part where the nodes are? Then you can deselect that edge when you define the contact surfaces.

 

[rstupplebeen]

Chop up your surface and define contact only on the part where you want it. The method of not using edge nodes would mean that contact would fall off 1 element width in and will be mesh dependent. If you have an irregular mesh your contact will be falling off of a jagged surface. I hope this helps.

Rob Stupplebeen

 

[satyasrinivas]

Thank you all for the suggestions.

The surface that I mentioned is a complex 3d surface that I generated in ProE. It does not have a regular geometry (e.g., square etc.,). So I am not very sure how to partition it.


The reason why I am trying to unpick an edge is to avoid over constraints on that edge.

I will go ahead and try some of your suggestions and will see how things go.

Thanks
SS

 

[gurmeet2003]

I have solved the same overconstraint problem by unpicking an edge using the cntrl key. It has always worked for me. Are you unable to resolve your overconstraint problem?

Gurmeet

 

[satyasrinivas]

Hi Gurmeet,

Unfortunately, I am not able to unpick the edges in the same manner (using the cntrl key) to exclude the edge nodes from the contact definition.

As soon as I edit the contact (using cntrl key), somehow all the edge nodes still reappear when the contact is higjlighted. Any suggestions ?

 

[DanStro]

I don't think there is a way other than partitioning. If it's really complex then you may have to use a lot of partitions of different types.

 

[rstupplebeen]

I am not a ProE guy but I am sure that partitioning the face in the native CAD program will be easier than in CAE. Search the help for "offset edge", "trim" or something like that. Don't get me wrong CAE is very capable for an FE program but it is not a dedicated CAD program. Can you post your part the native and or exported format? I hope this helps.

Rob Stupplebeen

 

[satyasrinivas]

Hi Rob,

Please find attached the geometry in my model in a stp file format. Please let me know how if you think I can use it to partition the inner edges (ie., edges that lie completely inside the upper model block). I will also look up into paritioning the face (using edge offset or trim options you suggested) in the meanwhile.

Thanks,
Rajesh