Learning Forum

[jay123856]

這是模擬器平衝壓成型的過程，外面還有一個外模具，我的沖壓頭會一直穿過鋁片，前面都已經試過contact了，後面用body interaction還是會穿過去 

[aabedini]

Hello Jay,

Try adding a contact pair (instead of Body Interactions) and scope it to the surfaces where the punch and die can touch, with a frictional behavior and a prescribed friction coefficient. You can disable or suppress Body Interactions.

If you still face the issue, try the following options: use a different SOFT option, adjust the contact stiffness, reduce the explicit time step, or refine the mesh.

You can also check the following articles: 

https://innovation.ansys.com/base/articles/topic/how-to-modify-contact-stiffness-in-ls-dyna-expu

https://innovation.ansys.com/base/articles/topic/how-is-contact-timestep-defined-in-ls-dyna-expu

 

 

[jay123856]

Thank you I will try what you said again.

[Dennis Chen]

I strongly suggest that you don't just use workbench by itself and just inserting objects to set up a dyna model.   Before you click solve, go to solution and export the input file and take a look at what's in there. 

body interaction usually translates into a single surface contact (0,0,5) that's not always the best.    a contact object often translates into a tied_offset or a automatic contact (depending on bonded vs frictional).   

A lot of the contact detection problems can be solved by changing the soft option or use other contact methods like contact_automatic_general.      FOr edge to surface, surface to surface, edge to edge contact, different contact keyword affects the response. 

It really bothers me when I see people use workbench like it's Ansys Mechanical for DYna, Dyna doesn't work like Ansys Mech at all, it has a lot more feature hidden that can be invoked inside workbench if you are not restricted to workbench's current design limits.