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Generating .vane file with transition cell and m=1 section

Posted: Mon 4 Nov 2024 09:51
by jhustings
I am attempting to generate a .vane file from the .dat file with the2termsflag. However, I struggle to get the end profile geometry correct. The lattice needs to end with a transition cell, followed by a flat m=1 cell and a fringe field. Unfortunately, I never succeed in the proper combination of both. Either the modulation of the transition cell is too low, or the m=1 cell is missing.

I have made many attempts where I adjust the cell type, cell length, and modulation of the last cells in the .dat file, but none gave me the desired result. Could you help me achieve a vane geometry where the transition cell has the proper shape, followed by a m=1 cell?

Re: Generating .vane file with transition cell and m=1 section

Posted: Mon 4 Nov 2024 13:04
by RomualdDuperrier
Hi

I would like to be sure about the problem you are highlighting. When I run Toutatis with your FromTraceWin.inp, I get the following vane profile at end:

vane_end.png
vane_end.png (25.24 KiB) Viewed 21 times
Does it match your expectation? If not, please describe more precisely the gap between your expectation and what is plotted there.

Best,

Romuald

Re: Generating .vane file with transition cell and m=1 section

Posted: Mon 4 Nov 2024 13:14
by RomualdDuperrier
Thinking more about the profile, if you want to produce a trancell not for the cell before the fringe field but the cell before, the code can not generate this because it will only apply trancell rules for the cell before the fringe field. But there is a work around, you can use an externally made .vane. So I suggest to proceed as follow:
1 run the code as you used to get a toutatis.vane with the right length for all the cells
2 modify with another tool (excel or script) the profile at the end to adjust the toutatis.vane => new_toutatis.vane.
3 modify FromTraceWin.inp by using theGeometryFileFlag 1 new_toutatis.vane
4 run the code again, in principle it should work.

I hope it helps,

Romuald

Re: Generating .vane file with transition cell and m=1 section

Posted: Mon 4 Nov 2024 15:09
by jhustings
Dear Romuald,

Thank you for the quick response! You are right, I would indeed like to apply the "transcell rules" to the cell before the flat section. I only manage to do this if I proceed directly to the fringe field. Your explanation confirms my suspicion that the combination of a transcell and a m=1 section is not possible.

I will have a go at the workaround that you suggest.

Thanks for the support!