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Solving multi domain (different diffusivity) Poisson-Nerst-Planck equation

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Hello all,

I am trying to solve multi domain (diffusivity is different from each region for c1, c2) Poisson-Nernst-Planck equation.
In order to do this, I am coupling electrostatic(es) module and Transport dilute species (tds) module.
In the case of dielectric constant, I can set different value by using 'from material'.

However, in the case of diffusivity, I cannot set each region different from each other.
I also tried using two (tds) module, however, I cannot converge them.
I always end up with the error 'Undefined variable.' and 'Failed to evaluate Jacobian of expression.'

Does anyone has good idea how to deal with this issue!?

2 Replies Last Post 26 mag 2016, 14:07 GMT-4

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Posted: 8 years ago 26 mag 2016, 06:14 GMT-4
Under tds module, define another "Transport properties" item and assign the other D value there.

BR
Lasse
Under tds module, define another "Transport properties" item and assign the other D value there. BR Lasse

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Posted: 8 years ago 26 mag 2016, 14:07 GMT-4
Thank you!

Now it works :)
Thank you! Now it works :)

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