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Migration problems in the physics of Transport of Diluted Species

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Dear Community,

I'm trying to add the migration phenomenon in the physics of Transport of Diluted Species, so I click "Migration in electric field" under the Transport Mechanisms, and input electric potential and charge number. (What I want to simulate is the ions transport in concrete and the self-induced electrical field created by the movement of the ions). But the problems is that no matter how large the electric potential I input, such as 1V, 100V, the 1D Plot of ions' concentration never changed. So I don't know which step has mistakes.

Does anyone have any ideas?

Best Iris



6 Replies Last Post Aug 6, 2018, 8:35 a.m. EDT

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Posted: 6 years ago Jan 29, 2018, 8:34 a.m. EST

You have only one electroactive species, which violates electroneutrality. You must add another ion, a counter-ion, a cation in the system. This applies also when the other ion is not actually moving (steady-state).

BR Lasse

You have only one electroactive species, which violates electroneutrality. You must add another ion, a counter-ion, a cation in the system. This applies also when the other ion is not actually moving (steady-state). BR Lasse

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Posted: 6 years ago Jan 29, 2018, 5:51 p.m. EST

Thanks for your answer. I've tried this method but it still doesn't work. The curve of the concentration never changed no matter how large the electric potential is.

Thanks for your answer. I've tried this method but it still doesn't work. The curve of the concentration never changed no matter how large the electric potential is.


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Posted: 6 years ago Jan 30, 2018, 2:54 a.m. EST

A constant potential does not cause migration, an electric field is required.

Lasse

A constant potential does not cause migration, an electric field is required. Lasse

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Posted: 6 years ago Feb 5, 2018, 12:41 a.m. EST

So should I add an Electrostatic physics field? Because adding an electric fied under migration option of Transport if Diulted Species doesn't work.

Tnanks and Best regards Iris

So should I add an Electrostatic physics field? Because adding an electric fied under migration option of Transport if Diulted Species doesn't work. Tnanks and Best regards Iris

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Posted: 6 years ago Jul 19, 2018, 10:55 a.m. EDT

Hey Dandan, I have a similar problem, did you ever find a solution for it. if yes how? And, would you be kind enough to share your model even if it is not succesful?

Luis

Hey Dandan, I have a similar problem, did you ever find a solution for it. if yes how? And, would you be kind enough to share your model even if it is not succesful? Luis

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Posted: 6 years ago Aug 6, 2018, 8:35 a.m. EDT
Updated: 6 years ago Aug 6, 2018, 8:43 a.m. EDT

Hi, You should also activate electric currents module. furthurmore, in transport of diluted module, you should use electric potential instead of user defined option in section of Migration in electric field. you can also view the attachmant.

Hi, You should also activate electric currents module. furthurmore, in transport of diluted module, you should use electric potential instead of user defined option in section of Migration in electric field. you can also view the attachmant.

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