What contact to use...
 
Notifications
Clear all

What contact to use for armor simulation in 2D (got error with 2Dautomatic_ surface_to_surface)

3 Posts
3 Users
0 Likes
784 Views
Posts: 4
Topic starter
(@wallyguy)
Barista
Joined: 4 years ago

I am trying to simulate a 2D axisymmetric model of a bullet impacting a single layered metal armor (as attached):

I am using Johnson Cook model with the Add_Erosion material model for both the parts. 2D_automatic_surface_to_surface is used to define the contact. My simulation runs at the start, but get very big distortions in some elements (as shown in the second image). I get the following error:

Error 40509 (SOL+509)
negative volume in solid element # 5219 cycle 86066

Error 40509 (SOL+509)
negative volume in solid element # 5219 cycle 86066
86066 t 3.8422E-05 dt-2.31E-07 write d3plot file 02/13/21 22:31:46
86066 t 3.8422E-05 dt-2.31E-07 write d3plot file 02/13/21 22:31:46

Does anyone know what I can do to solve this? Any help would be greatly appreciated!

Screenshot 2021 02 13 223419
 
 
Screenshot 2021 02 13 224312
2 Replies




Negative Volume
Posts: 639
Admin
(@negativevolume)
CEO
Joined: 5 years ago

Hi @wallyguy

If you are using *Mat_add_erosion you should change your contact to incorporate the 3D aspect of the part that is eroding. Otherwise, your bullet will just pass through those elements under the top layer. Maybe try *Contact Surface to Surface and use parts for both the slave and master type, the 2D bullet as the msid and the 3D plate as the ssid?

You also need *Contact_interior and reference a part set with the 3D plate. This helps deforming materials stability. 

Reply
1 Reply
(@sheida)
Joined: 3 years ago

Paid Intern
Posts: 14

Hi @negativevolume

I have the same problem, but I do not use *Mat_add_Erosion. I used *Contact 2D automatic node to surface but I got different results with the experimental data. The paper I am using for validation employed an automatic 2D single surface penalty. It is for 2002. There is not such a type of contact in LS-DYNA. I used 2D automatic single surface and 2D penalty together, but it gives me an error termination. I also tried only a 2D automatic single surface, but it resulted in no contact after running the model. 

I would appreciate it if you could let me know if you have any suggestions regarding appropriate contact for this model. Do I have to use *Contact Interior as well?

 

Thank you, 

Sheida

Reply







Share: