Learning Forum

[GongCheng Peng]

Hello,

A problem occurred when we needed to simulate an electromagnetism problem with FEM-BEM; we needed to simulate magnetic pulse welding. The magnetic pulse welding process is shown in Figure 1。 We want to simulate the deformation process of the flyer plate using Dyna simulation.

Figure 1

I could get the simulation results perfectly when my flyplate was just aluminium as shown in figure 2.

 

However, when I add aluminum foil to the aluminum plate, as shown in Figure 3, the dyna does not give me any results or will not converge.

Figure 3

Why is Dyna not able to calculate the results? We desperately need to simulate the deformation of aluminum plates and foils; 

Using R15 MPP double precision.

Please help me.

Regards

 

 

[Reno Genest]

 

Hello,

What are the differences between the model that gives you good results and the model that does not work?

Do you have error or warning messages?

Note that Ansys employees are not allowed to upload and download models on the Ansys Forum. You can still post your model here and another user may be able to assist you.

 

Reno.

 

[Ushnish Basu]

What are the distances between conductor faces and do they respect the general best practice rule that the distance between BEM faces should not exceed the surface mesh size? From the pictures it does not appear to be the case. Remedies to this when a lack of convergence is observed is to either improve the mesh (usually via refinement), reduce the time step, tighten the tolerances of the BEM matrices assembly etc. etc., usually a combination of all those factors. In other words, improve the model (also, the mesh seems uniform everywhere so probably an overkill in regions where little might happen).

 

Please also see the youtube viedo series on EM forming (search for "ls dyna em forming tutorial")