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larger ICP model causing problems - singularity error

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Hey,

I am using your thermal_plasma model as a basis to my model. It is almost the same. The only difference is that in my model the tube is straight (not curved) and longer (0.8 m). These are the dimensions of an ICP system we use in our plasma laboratory.
If I leave dimensions intact (length of 0.8 m) I always get a solver error (singularity). If I shorten the tube to about 0.2 m the solution works fine. Is there any solution to this problem?

Thank you,
Regards

4 Replies Last Post 29 mag 2013, 22:04 GMT-4
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Hello Gregor Primc

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Posted: 1 decade ago 6 mar 2013, 19:59 GMT-5
I have the same problem when I set a large radius. The computing time always stops in 3~7E-6 s. And, if I sat the current in coils 0 A, the solver works fine. However, even current setted as 1 A, the solver will stop too. I hope somebody can give me a little help. My email: lisen_seu@126.com. Thanks very much!
I have the same problem when I set a large radius. The computing time always stops in 3~7E-6 s. And, if I sat the current in coils 0 A, the solver works fine. However, even current setted as 1 A, the solver will stop too. I hope somebody can give me a little help. My email: lisen_seu@126.com. Thanks very much!

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Posted: 1 decade ago 19 mag 2013, 02:03 GMT-4
HI,

Have you got your problems solved?

In fact, I encountered the same question: when I modified the PECVD model to design my own model, as long as I changed the parameters, the results would not be converged. Always, a singularity will occur, stopping me from delving further. So if somebody knows how to solve such kind of errors, please give me some hints.

My e-mail address is wangwq1990@gmail.com. ^^

Thank you

Wiky
HI, Have you got your problems solved? In fact, I encountered the same question: when I modified the PECVD model to design my own model, as long as I changed the parameters, the results would not be converged. Always, a singularity will occur, stopping me from delving further. So if somebody knows how to solve such kind of errors, please give me some hints. My e-mail address is wangwq1990@gmail.com. ^^ Thank you Wiky

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Posted: 1 decade ago 20 mag 2013, 00:47 GMT-4
Hey Wenqi Wang,

if you get the solution to the problem, please e-mail it to me as well: primc.grega@gmail.com

Thanks!

Best Regards
Hey Wenqi Wang, if you get the solution to the problem, please e-mail it to me as well: primc.grega@gmail.com Thanks! Best Regards

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Posted: 1 decade ago 29 mag 2013, 22:04 GMT-4

Hello,

the plasma module looks very fine, but as to see the activity in this community forum, it looks like it has no great success?

i face the same convergence problems.. it is tough..

what are the strategy to improve the model?

i record all time steps..
try to find out some e-temperature spikes, follow the power supply (circuit model) and so on..

but still I have no clue how to improve the whole thing..

what are your values for secondary electron emissions?

let us share our experiences..

lukas
Hello, the plasma module looks very fine, but as to see the activity in this community forum, it looks like it has no great success? i face the same convergence problems.. it is tough.. what are the strategy to improve the model? i record all time steps.. try to find out some e-temperature spikes, follow the power supply (circuit model) and so on.. but still I have no clue how to improve the whole thing.. what are your values for secondary electron emissions? let us share our experiences.. lukas

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