At least one contact pair has no elements in it 3

[Pingen]

Hi,

In WB.

I get the following error message:

"At least one contact pair has no elements in it. This may be due to mesh based defeaturing of the geometry. Set the variable "contactAllowEmpty" to 1 in order to allow the solution to proceed with an ANSYS warning which can be used to identify the offending pair(s)."

How do I set contactAllowEmpty = 1?

Pingen

 

[cbrn]

Hi,
never seen anything like this. However, if it's a variable, then you may declare it as

contactAllowEmpty=1

just like a parameter, in a Commands snippet right in the Contacts branch. I'd say, not in the Environment branch because these commands would be processed after the contact pairs' setup.

Or in some way you may use the WB SDK, but I have no hint about it, I've never used it.

Hope this helps

Regards

 

[Pingen]

Thanks.

I cannot put a Commands snippet immediately under Contacts. It seems, the snippet must go under a specific Contact Region. I tried and put it under the top most Contact Region and the error remains.

Pingen

 

[cbrn]

Hi,
look at the Solution Information in order to troubleshoot which is the contact pair that runs into error. In order to retrieve the contact pair, one method is to open the Environment in the Classical interface and, by selecting / unselecting elements, find out the correspondance between the contact pair and the Contact you've defined in WB.
In fact, if you have several Contacts defined in WB, putting the snippet under the topmost object is not necessarily correct: the contact in error could be the third, the seventh, the n-th...
OK, brute-force trial would be to duplicate the snippet for every Contact defined.
But first of all, track in the Solution Information where it reads the parameter definition "contactAllow...etc" to see what it does at that point.

Regards

 

[Pingen]

Hi,

Solution Informaion is empty, completely.

I put a copy of the snippet in each of the many contacts, but the problem remains.

I'll get in touch with the support and bring an update on what they come up with.

Thanks for you egagement.

 

[Pingen]

So, contactAllowEmpty is a system variable that one can create and set through the Control Panel (Windows). The variable must also be added in Variable Manager.

The problem was likely caused by distorsion of the actually geometry, due to imperfections of the meshing. Introducing contactAllowEmpty, as described, should eliminate the problem.

Pingen

 

[doatis]

Don't know if anyone has specifically told where to add the variable...

Within Simulation:
Tools > Variable Manager

In the window that pops up, right click in either cell and select 'Add'. Then set the variable name to be contactAllowEmpty, and its value to be 1.

Hope this helps,
Doug