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weak constraint in" benchmark model of ccp"

Posted Nov 21, 2014, 5:58 a.m. EST Plasma Physics Version 4.4 2 Replies

Youb HM
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Hi ,guys. I am confused by the use of weak constraint in model library ”Benchmark model of a capacitively coupled plasma" .more specific I don't understand why "J_total= intop1(-d(V_lm,t))" ,ie the total current density equals the time derivative of the Lagrange multiplier of electric potential.
Could you guys tell me what indeed "V_lm" is and how it relates to the total current density at the driven electrode? Thanks a lot!
2 Replies Last Post Nov 21, 2014, 3:53 p.m. EST
Daniel Smith COMSOL Employee

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Posted: 10 years ago Nov 21, 2014, 9:03 a.m. EST
V_lm corresponds to the normal electric displacement flux, n . D from Poisson's equation. Thus, -d(V_lm,t) represents the displacement current density. Weak constraints are needed to get an accurate solution. In V5.0, the model has been updated to use the new Terminal feature, which allows you to simply type in an expression for the Terminal current. All of the correct equations are now generated under the hood. You can see this in the same model in V5.0.
V_lm corresponds to the normal electric displacement flux, n . D from Poisson's equation. Thus, -d(V_lm,t) represents the displacement current density. Weak constraints are needed to get an accurate solution. In V5.0, the model has been updated to use the new Terminal feature, which allows you to simply type in an expression for the Terminal current. All of the correct equations are now generated under the hood. You can see this in the same model in V5.0.
Youb HM
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Posted: 10 years ago Nov 21, 2014, 3:53 p.m. EST
Thank you very much
Thank you very much

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