# Boundary condition issues

I have been trying to make a 3 roller bending machine simulation to see how aluminum extrusions of different cross-sections bend to predict their bendability and minimum radius. The 3 rollers are made of nylon and the extrusion is aluminum 6063 T6. It is a U-section extrusion and is tightly packed with nylon filler material to support the extrusion while bending. I haven’t been able to produce a converging solution even after running for more than 5 hours. Please help me setup the boundary conditions.
link to the video showing actual machine: https://youtu.be/gwczLyil6h0?si=VZIErY3DOlg-UW6G

Hello!

Make sure to post a link to your project as well, so it’s easier to access it.

Quick note: you will likely have to revisit the strategy to make the parts rotate. Looking at the YouTube video, the base point definition looks weird to me for all 3 rotating parts. The physical contact will likely require friction.

Cheers

Hello!
Thank you for the reply. I have made some changes applying frictional conditions. For the rotating parts there is no translation for the rollers other than the middle one. So I just defined base point as (0,0,0). and for the middle roller I used remote displacement condition to incorporate both rotation and translation where the base point I modified to be the center of the roller. But still my simulation run failed. Please see my run 8 in the project for failure reason.

The base point is the point around which the rotation takes place. E.g. for the 2 rollers defined with a rotating motion boundary condition, you are going to get a motion like this around the current base point (0, 0, 0).

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@RicardoParis
Hi, Thank you for taking out time to help me. I have changed the basepoints to the center of the rollers and have started another simulation run. But after 50 min I see in solver log “convergence conditions has reached” and still is at 0% after 70 mins (same case with the runs before. I let them run for more than 5 hours hoping it calculates but stays at 0%, so I cancelled them for previous runs). I am relatively new to structural problems so I am unable to identify what’s wrong. Please let me know what I should do. Let it run or is there anything fundamentally wrong with the setup?

Thank you

edit 1: it reached 5% after 80 min, for the first time it progressed from 0%.
edit 2 :after running for roughly 7.5 hours it progressed 9% and got terminated as it reached the maximum time limit.

Hello, I tried to reduce the number of elements and run the simulation as the previous run terminated due to exceeding its maximum computational time. Any help would be appreciated as I am clueless where I am going wrong.