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[tut06916]

Hi All, 

I created 2 beams. After I applied cross section, there was an overlap between the two beams. I applied *contact_automatic_general between 2 beams. I found the beam would repel each other because there is model overlap. Does anybody know how to get rid of the repulsive force, even though there is overlap?

[peteroznewman]

Don't apply *contact_automatic_general between 2 beams.

[tut06916]

Thank you for your reply.

[tut06916]

Hi Peter,  I created a dome composed of many beams as shown in the figure 1 and 2, and made a cylinder imapct it. I applied *CONTACT_AUTOMATIC_BEAMS_TO_SURFACE_ID between the cylinder and each beam. As for beams, there is a little difference in height between 2 beams. I didn't add any contacts. I added *CONSTRAINED_GENERALIZED_WELD_SPOT or *CONSTRAINED_SPOTWELD between the nodes of 2 beams closest to the intersection. After I ran the simulation, the cylinder went through the dome rather than impacting it, as shown in figure 3. The beams appeared to have a little oscillation. It seems that there is still some interaction force between the beam and the cylinder. But the cylinder just directly went through the beams. Do you know how to fix it?

I attached my .k file. Could you please take a look?  : https://tuprd-my.sharepoint.com/:u:/g/personal/tut06916_temple_edu/IQAtEDBPZhKLRYw4Kr0EEa_AAeYXal-n6FkEF1ROSpG_67k?e=86nLOW

Thanks

 

[Nanda]

Hello User,

Peter is correct. *CONTACT_AUTOMATIC_GENERAL, uses segment-based contact logic, which doesn't map well to 1D beam elements. You should explore *CONTACT_AUTOMATIC_BEAMS_TO_SURFACE.

Regards,

Nanda.

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[tut06916]

Hi Nanda, I tried *CONTACT_AUTOMATIC_BEAMS_TO_SURFACE. And there is no repulsive force between beams. So *CONTACT_AUTOMATIC_BEAMS_TO_SURFACE doesn't take the initial model penetration into consideration? What's the logic behind this contact?