To model the contact between two components, I used the contact volume function as recommended in another topic. Due to the small distance between the two modeled components, the boundary surfaces of the contact volumes also have a very small height. During mesh generation, the error appears only on three of these boundary surfaces: "Surface No. 21 has no 2D FE element | This can occur if a node support of type 'fictitious support' covers the entire surface."
I experimented a bit with different mesh refinements, but even with the smallest possible one, this error appears, in this case for surface No. 0(?).
I do not understand why this problem occurs only on some of the boundary surfaces and also why surface No. 0 was named as the error location with a finer mesh. I would be grateful for a solution to this problem!
Kontaktvolumen_Holz.rf6 (1.3 MB)
Best regards
Hello Baustudi 
,
the problem probably lies in the fact that the two contacting surfaces (20, 23) of contact volume 8 are not congruent.
One proposed solution would be to cut the lower surface as follows:
Please try that first. If there are still problems afterwards, feel free to get back to us – we will find a solution! 
Best regards
Matthias
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Hello Matthias,
Thank you very much! I'll try to implement that, of course it's a bit tricky with the geometry of the volumes. 
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Hello Matthias,
In the meantime, I have remodeled everything again, paying attention to the identical size and parallelism of the contact surfaces. Unfortunately, the mesh generation still does not work perfectly. It outputs that the topology of contact volume no. 12 is faulty. Unfortunately, I do not know where the error is now, as the surfaces should be parallel and the same size, and no other elements lie on the surfaces. Could you please help me again at this point?
Kontaktvolumen_neu.rf6 (3.8 MB)
Many thanks and best regards
Baustudi
Hello Baustudi,
unfortunately, there are some errors in the model that I can no longer fully trace afterwards. 
My suggestion would be to recreate the model step by step. After each step, you can test whether the calculation runs correctly. 
I am happy to support you and help you step by step!
Best regards
Matthias
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Hello Matthias,
thank you very much for the tip. The error in the network generation occurs as soon as I have modeled the contact volume between areas 2 and 9: Faulty topology of contact volume no. 9.
Kontaktvolumen_schritt fĂĽr schritt.rf6 (1.2 MB)
Do you have any idea where the error might be?
Best regards
Baustudi
Hi Baustudi,
you need to reduce the maximum distance between a node and a line to integrate it into the line. It worked for me when I set it to 0.001 cm.
Presumably, this distance between the two contact surfaces of the contact volume is causing problems here:
If you have any further questions, feel free to get in touch 
Best regards
Matthias
Hello Matthias,
thank you very much! That was super easy to fix 
.
The mesh of the version is finally working now as well.
I now also wanted to merge the small free areas between the contact volumes into one contact volume (I'm not entirely sure how necessary this is) - see volume 14. Here, the warning of a faulty topology appears again. Do you perhaps have a solution for this as well?
Kontaktvolumen_kleine Kontaktvolumen.rf6 (1.3 MB)
Thank you very much and best regards
Baustudi
Hi Baustudi,
the problem is that this closes another contact volume laterally.
Actually, I see no need to model volume 14, as it is empty slip anyway. I would simply leave this intermediate space empty.
Best regards
Matthias
Hello Matthias,
all clear. Many thanks for all your help!
By changing the maximum distance, the mesh generation now actually works with the model with surface contacts.
All best regards!
Baustudi