Plasma Module - Latest Discussions - COMSOL Forums

time evolution of surface charges ...

Sat, 04 Feb 2012 07:29:29 +0000

Hi,

How can one compute time evolution of surface charges in argon_dbd_1d example?
There is not any option to show/plot it in COMSOL.

Thanks again,
Mona

time evolution of surface charges ...

Sat, 04 Feb 2012 07:27:42 +0000

Dear Ivar,
Hi,

First thanks a lot for your kind attention and replies.
I have another question. How can one compute time evolution of surface charges in argon_dbd_1d example?
There is not any option to show/plot it in COMSOL.

Thanks again,
Mona

time evolution of surface charges ...

Sat, 04 Feb 2012 07:26:44 +0000

Dear Daniel,
Hi,

First thanks a lot for your kind attention and replies.
I have another question. How can one compute time evolution of surface charges in argon_dbd_1d example?
There is not any option to show/plot it in COMSOL.

Thanks again,
Mona

positive_column_1d example ...

Tue, 31 Jan 2012 05:17:13 +0000

Dear Edgar

Hi,

In positive_column_1d example in Plasma Module :

I receive the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V :

Repeated error test failures. May have reached a singularity.
Time : 4.778827037879742e-006
Last time step is not converged.

This massage also occurs for other examples.
How one can resolve this difficulty ?

In my work, I need to increase the voltage to several kV and e.g. 20 microsecond.

Thanks a lot for your kind attention in advance.

Kind Regards,
Mona

positive_column_1d example ...

Tue, 31 Jan 2012 05:15:18 +0000

Jean-Francois

Hi,

In positive_column_1d example in Plasma Module :

I receive the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V :

Repeated error test failures. May have reached a singularity.
Time : 4.778827037879742e-006
Last time step is not converged.

This massage also occurs for other examples.
How one can resolve this difficulty ?

In my work, I need to increase the voltage to several kV and e.g. 20 microsecond.

Thanks a lot for your kind attention in advance.

Kind Regards,
Mona

positive_column_1d example ...

Tue, 31 Jan 2012 05:11:51 +0000

Hi,

In positive_column_1d example in Plasma Module :

I receive the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V :

Repeated error test failures. May have reached a singularity.
Time : 4.778827037879742e-006
Last time step is not converged.

This massage also occurs for other examples.
How one can resolve this difficulty ?

In my work, I need to increase the voltage to several kV and e.g. 20 microsecond.

Thanks a lot for your kind attention in advance.

Kind Regards,
Mona

positive_column_1d example ...

Tue, 31 Jan 2012 05:09:23 +0000

Dear Ivar

In positive_column_1d example in Plasma Module :

I received the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V :

Repeated error test failures. May have reached a singularity.
Time : 4.778827037879742e-006
Last time step is not converged.

This massage also occurs for other examples.
How one can resolve this difficulty ?

In my work, I need to increase the voltage to several kV and 20 microsecond.

Thanks again a lot for your kind attention in advance.

Kind Regards,
Mona

positive_column_1d example ...

Tue, 31 Jan 2012 05:08:29 +0000

Dear Daniel

In positive_column_1d example in Plasma Module :

I received the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V :

Repeated error test failures. May have reached a singularity.
Time : 4.778827037879742e-006
Last time step is not converged.

This massage also occurs for other examples.
How one can resolve this difficulty ?

In my work, I need to increase the voltage to several kV and 20 microsecond.

Thanks again a lot for your kind attention in advance.

Kind Regards,
Mona

Gaussian laser pulse into plasma bulk

Mon, 30 Jan 2012 08:30:53 +0000

hi
i am new to Comsol. i would like to simulate propagation a Gaussian laser pulse into plasma bulk.
could anybody help me?
thanks
Shahang

My owen expression

Wed, 25 Jan 2012 08:19:29 +0000

Hello,

I would ask if I can add my expressions to the results (calculation of centripetal forces ...)?

Thank you.

Frequency transient dont work

Mon, 23 Jan 2012 15:55:31 +0000

Hi.

I choose from the model library model.
This model has a frequency of transient study.
Once there I will make some changes ,the frequency of transient stops working but the time domain
with the same setup is working normally.

Why because the only difference is that the time domain does not subcontract any frequency?

Thank veri much.

Repeated error test failures

Thu, 19 Jan 2012 16:54:31 +0000

Hi.

I build new model Plasma DD along pdf from Comsol help.
But get this error

Repeated error test failures. May have reached a singularity.
Time : 2.856867412349752e-008
Last time step is not converged.

Can enybody help me with this?

Thank.

Error Circular variable dependency detected.

Wed, 18 Jan 2012 10:06:58 +0000

Hi,

I got this error
Circular variable dependency detected.
- Variable: mod1.icp.sigmazz
- Geometry: 1
- Domain: 2 3 5
Whot it is mean ?

Variable sigma have defined in material browser.

Thank very much.
By.

Help with outplots in Comsol

Sun, 15 Jan 2012 12:01:22 +0000

Hello.

I do not distracting you again but I have another problem.
When I open the surface and add a list of "+"
choose the output somehow.
This is added to the expression that was already in surface box and there is usually nonsense.
Or add a new expression of the surface and when I walk through the editbox mouse so my new expression transcript of the olds..

Thank you very much.

Wrong number of dofs in initial value.

Sun, 08 Jan 2012 17:06:48 +0000

I have new model and new error:

Pleasse help me:

Time depndent study:

Wrong number of dofs in initial value.

Whot is it dofs ?

Thank.

DBD example in COMSOL ...

Sun, 25 Dec 2011 14:43:47 +0000

Dear Daniel,

I really would be grateful if you can advise me about the following subject about DBD example in COMSOL. Please see the current density across gap and in coatings.

1- It is not equal in two coatings. Does it break KCL rule?
2- Is the current density in coatings based on second equation in Surface Charge Accumulation section in page 41 of User Guide, Version 4.0 Beta? In other words, is it due to surface charges? Why can one obtain the surface charges?

Kind Regards,
Mona

Plasma arc

Thu, 22 Dec 2011 21:13:38 +0000

Hi,

I'm trying to simulate a plasma arc speaker (a sound generator based on the vibration of a ionized arc). I have setup a CCP module (I hope correctly... is the first time I use this physics), but now I don't know how I can read the result (how to understand if with the applied voltage the arc is generated and how it moves in time)

Anyone have experiencies of similar problem?

Thanks!!

Question about External surface charge accumulation

Fri, 16 Dec 2011 17:35:37 +0000

Hi, Daniel

Is dc discharge model congaing both of ground and dielectric boundaries necessary condition?

I found out that if I set the wall is zero charge condition(metal wall) instead of dielectric wall(External surface charge accumulation) , it is hard to get the converged solutions.

Can you explain this?

Thank you~

Problems of users defined EEDF interpolation function (welcome Mr. Daniel Smith to come in)

Fri, 16 Dec 2011 14:06:41 +0000

Hi,
I try to model the discharge which is non-Maxwellian EEDF.

Use Two-term approximation to build the electron energy distribution (as model library examples).

According the plasma module user’s guide, I creat the spreadsheet data form as following:
% x y f
0 4.022555e+000 1.654768e-001
1.038868e-001 4.022555e+000 1.647795e-001
2.159485e-001 4.022555e+000 1.642455e-001
.
.
.
note: x is electron energy(eV), y is the mean electron energy(eV), f is EEDF
Then, I use the above file to build the 2D interpolation function.

However, I got the error message as solving the model:

Internal error in mesh initialization.
Error in multiphysics compilation.
- Detail: Degenerated bounding box.

My questions are:
1. What is wrong of the 2D interpolation function?
2. The users defined EEDF is correct form?

I need any suggestions or help.

Thanks~

Dielectric B.C. in Plasma Module

Tue, 30 Aug 2011 19:35:03 +0000

Hello All,

I am trying to adapt the 2D argon_gec_icp file to have a dielectric boundary at the walls of the plasma domain. For this purpose I would like to use Surface Charge Accumulation as an Electrostatic boundary condition, but all boundaries appear as "not applicable". Does anyone know the reason for this? Better yet, does anyone have a suggestion for implementing the dielectric boundary condition properly?

Thank you,
Sonya