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error test failures

Posted 2 gen 2014, 06:22 GMT-5 Plasma Physics, Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 4.2a, Version 4.3, Version 4.3b 2 Replies

Amir Zamani
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hi
i use ccp module for simulation,my time range is range(0,5e-5,0.001) but when i compute model times go 7.579247e-019 to this and report this error
Repeated error test failures. May have reached a singularity.
Time : 7.579247088737066e-019
Last time step is not converged.

how can i solve it?
thanks
2 Replies Last Post 3 set 2014, 08:03 GMT-4
Luke Gritter Certified Consultant
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Posted: 1 decade ago 6 gen 2014, 11:25 GMT-5
Amir,

Capacitively coupled plasma models often have convergence problems due to the sheath dynamics and the large number of cycles required to reach periodic steady state. Here are a few items that can help facilitate convergence:

1) Avoid sharp corners (especially on the electrodes)
2) Use a very fine mesh everywhere the gradients associated with the sheath will appear during the solution process
3) Make sure you are using realistic electron transport coefficients and ion mobilities

Good luck!
--
Luke Gritter
AltaSim Technologies
Amir, Capacitively coupled plasma models often have convergence problems due to the sheath dynamics and the large number of cycles required to reach periodic steady state. Here are a few items that can help facilitate convergence: 1) Avoid sharp corners (especially on the electrodes) 2) Use a very fine mesh everywhere the gradients associated with the sheath will appear during the solution process 3) Make sure you are using realistic electron transport coefficients and ion mobilities Good luck! -- Luke Gritter AltaSim Technologies
Zhiming Huang
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Posted: 1 decade ago 3 set 2014, 08:03 GMT-4
See you again Mr. Gritter！
And I meet the same problem——
"Repeated error test failures. May have reached a singularity.
Time : 1.000005239532391e-007
Last time step is not converged."

The model is a dielectric barrier discharge , and the domain is a rectangle, I add the Electic Potential to the upper edge, --- will it be the sharp corners that results in the erro?
See you again Mr. Gritter！ And I meet the same problem—— "Repeated error test failures. May have reached a singularity. Time : 1.000005239532391e-007 Last time step is not converged." The model is a dielectric barrier discharge , and the domain is a rectangle, I add the Electic Potential to the upper edge, --- will it be the sharp corners that results in the erro?

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