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Using a previously obtained electric potential as the electric potential in the Nernst-Planck equations interface
Posted Aug 24, 2012, 2:30 p.m. EDT Low-Frequency Electromagnetics, Chemical Reaction Engineering, Results & Visualization Version 4.2 1 Reply
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Hello,
I've calculated an electric potential distribution using the electric currents interface, and now I need to use that electric potential in the migration term of the Nernst-Planck equation. I’m not sure how to couple both physics. I thought about simply typing V for the electric potential in the dependent variables of the Nernst-Planck equations interface, but I don’t know if Comsol would recognize it as the electric potential I obtained previously (it's the same model). I’d really appreciate if someone could help me with this, and I'm sorry if it's a silly question, but I have very little experience using Comsol.
I have a second question. I’ve plotted the electric potential along the line defined by the intersection between a sphere and a plane. It’s a V versus arc length line-graph. When I replace the sphere with, let’s say and oblate spheroid, I get a graph that is what I was expecting, but the arc length obviously changes. I was wondering if it’s possible to plot the electric potential against a normalized arc length directly in Comsol, for uniformity reasons.
Thanks in advance.
I've calculated an electric potential distribution using the electric currents interface, and now I need to use that electric potential in the migration term of the Nernst-Planck equation. I’m not sure how to couple both physics. I thought about simply typing V for the electric potential in the dependent variables of the Nernst-Planck equations interface, but I don’t know if Comsol would recognize it as the electric potential I obtained previously (it's the same model). I’d really appreciate if someone could help me with this, and I'm sorry if it's a silly question, but I have very little experience using Comsol.
I have a second question. I’ve plotted the electric potential along the line defined by the intersection between a sphere and a plane. It’s a V versus arc length line-graph. When I replace the sphere with, let’s say and oblate spheroid, I get a graph that is what I was expecting, but the arc length obviously changes. I was wondering if it’s possible to plot the electric potential against a normalized arc length directly in Comsol, for uniformity reasons.
Thanks in advance.
1 Reply Last Post Aug 24, 2012, 4:06 p.m. EDT
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Posted:
1 decade ago
Hi,
It is possible the way you have thought, except that it is better to use the identifier alongwith the variable name, i.e. mod1.V instead of just V (I think...).
Run your electric current as Study 1.
Run your voltage problem as Study 2. But here you invoke results from study 1. This you do by going to Solver settings. Under Study 2, Step 1 (stationary or transient or whatever), expand the tab "Values of Dependent Variables", select method as "Solution" and select Study "Study 1". Run the problem.
This is one way of solving it. Things are much better explained in the manuals.
Suresh
It is possible the way you have thought, except that it is better to use the identifier alongwith the variable name, i.e. mod1.V instead of just V (I think...).
Run your electric current as Study 1.
Run your voltage problem as Study 2. But here you invoke results from study 1. This you do by going to Solver settings. Under Study 2, Step 1 (stationary or transient or whatever), expand the tab "Values of Dependent Variables", select method as "Solution" and select Study "Study 1". Run the problem.
This is one way of solving it. Things are much better explained in the manuals.
Suresh