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surface charge, weak form boundary,time-depended
Posted 21 apr 2017, 15:15 GMT-4 Version 3.5a 2 Replies
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Hi everyone
I want to model a discharge use Poisson's equation and the conservation equations (electrons and positive ions). (1 dimesion)
But on one of the boundarys i should use the following condition for Poisson's equation, and I do not know how?
n.(D1-D2)=sigma ====================> i khow how do this
dsigma/dt = - (electron' charge)*(sum electron flux and ions flux) =======> i don't khow how do this?
sigma is surface charge due to "The flux of charged particles"
Apparently should be used "weak form,boundary" node (time-depended Analysis) but i don't khow how?
please guide me with details.
thanks
I want to model a discharge use Poisson's equation and the conservation equations (electrons and positive ions). (1 dimesion)
But on one of the boundarys i should use the following condition for Poisson's equation, and I do not know how?
n.(D1-D2)=sigma ====================> i khow how do this
dsigma/dt = - (electron' charge)*(sum electron flux and ions flux) =======> i don't khow how do this?
sigma is surface charge due to "The flux of charged particles"
Apparently should be used "weak form,boundary" node (time-depended Analysis) but i don't khow how?
please guide me with details.
thanks
2 Replies Last Post 22 apr 2017, 03:47 GMT-4
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Posted:
8 years ago
Avat,
I have been working on this problem for a few months. My strategy was to add a PDE to the model and defining the equation for surface charge density there.
Your model is more complicated as it includes charged particles. For this, you may add a "transport of dilute species".
Please keep me updated about your success and feel free to share your ideas with me.
Amin,
I have been working on this problem for a few months. My strategy was to add a PDE to the model and defining the equation for surface charge density there.
Your model is more complicated as it includes charged particles. For this, you may add a "transport of dilute species".
Please keep me updated about your success and feel free to share your ideas with me.
Amin,
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Posted:
8 years ago
hi my friend!
Because of the large number of equations and the great number of coefficients of reactivity, the probability of singularity is very high and at the boundarys should be weak form.
I think that the most complex part of comsol is weak form (for subdomains ,boundarys and points).
Because of the large number of equations and the great number of coefficients of reactivity, the probability of singularity is very high and at the boundarys should be weak form.
I think that the most complex part of comsol is weak form (for subdomains ,boundarys and points).