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February 3, 2012, 13:55 |
Help: "Ions-Transport"
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#1 |
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Hello guys; first, sorry for my bad english .
I have to simulate a single-phase system, with anions and cations diffuse in an aqueous solution. Ions and cations are obviously scalars. How can I insert the effects due to electrical interactions? How can I insert the condition: C = A in each element (electroneutrality)? where A and C are the concentrations of anions and cations, respectively thanks Last edited by CrisCFD; February 4, 2012 at 06:32. |
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February 4, 2012, 10:34 |
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#2 |
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Maybe I didn't explain well...
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February 5, 2012, 17:18 |
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#3 |
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Glenn Horrocks
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If A=C then why model two concentrations? Just model one and the other will be the same. This is easily done with a additional variable.
But I do not know what electrical interactions you wish to include. |
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February 6, 2012, 03:47 |
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#4 | |
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Quote:
I have to consider the electrical interactions in the transport equation as an additional term, as a source term. I just found an expression like this: S+ = - σ / ε * (C-A) and S- = σ / ε * (C-A) But the very low value of the costant "ε " (dielectric constant = 2,21 E-10) is a problem for the solver, a numerical problem, I think. |
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February 6, 2012, 19:06 |
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#5 |
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Glenn Horrocks
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But again, you said A=C so the expression evaluates to zero.
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February 7, 2012, 03:27 |
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#6 |
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