Metal forming

14 Mar 25

When I use mesh adaptivity in my stamping simulation I don’t know how to define the proper adaptive frequency. Would you please give me some suggestions?

It depends on the specific case. If the initial mesh is too coarse, it is necessary to have a very…

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14 Mar 25

When I use the implicit method to do springback analysis I cannot obtain a converged solution no matter what I’ve done. Do I have some other choices to obtain a converged solution for springback prediction?

Yes, you still have one more choice to get a converged solution. In LSDYNA3D, if you cannot get a converged…

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14 Mar 25

When I used coarsening, I found that there is an error message:’ Something is wrong, sub: nextele’. What is the problem, and how can I avoid it?

When the normal of the initial blank mesh is not uniform, this problem might happen. It is easy to avoid…

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14 Mar 25

When I used implicit method to do springback analysis, the iteration information was not output or displayed in the screen. I think this iteration information is important for me to monitor the convergence status. How can I display this information?

In the card of *CONTROL_IMPLICIT_NONLINEAR, there is a parameter NLPRT (the fourth parameter in the second line of this card),…

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14 Mar 25

When I used switch method in my calculation, I used explicit method and then I changed to implicit method. In the later implicit calculation process, it was seen that the contact didn’t work properly. What was the problem, and how can I avoid this?

In implicit analysis, the constraint approach for FORMING contact is not implemented (this contact is activated when SOFT=4, the first…

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14 Mar 25

When I used the seamless method to do both forming and springback analysis, a converged solution wasn’t obtained. I don’t want to repeat the forming analysis. Is there a way I can repeat the springback analysis from the previous output files?

There are two ways to repeat the springback analysis: a) Generate a ‘dynain’ file from the d3dump01, which was generated…

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14 Mar 25

When the constraint contact is used, the calculation crashes during the forming analysis. What needs to be done to prevent this?

There is a limitation in the constraint method. It is not permitted to have constrained contact on both sides of…

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14 Mar 25

When we do springback analysis, we have two choices to do it, i.e. using implicit and explicit method (dynamic relaxation). What is the advantage of using the implicit method in springback analysis?

Springback process is purely a static process, and if dynamic relaxation is used, the CPU cost will be prohibitive long…

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14 Mar 25

Why does the restart of the springback analysis not work?

I attempted to restart the springback analysis from the d3dump01. The springback analysis was not performed even though the “message”…

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14 Mar 25

Why dynamic relaxation doesn’t seem to work at times?

For the analysis of static loading process, such as gravity loading, dynamic relaxation method is commonly used with the keyword…

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