Solution of Fick's law with concentration dependent diffusion

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Solution of Fick's law with concentration dependent diffusion

tkdiff
Can FEATool be used to solve Fick's diffusion PED using non-linear concentration dependent diffusion?  I have tried a 1D problem using realistic numbers (C0 of 1e20 and D0 of 1e-11) using a flux boundary on the left and get a result, but only after hours of solution time (time dependent, internal solver, 0.2 time step for 1000 total time)
Any comments to help me understand this would be welcome.
Thanks.
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Re: Solution of Fick's law with concentration dependent diffusion

tkdiff
Figured it out myself.......learning curve problem.
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Re: Solution of Fick's law with concentration dependent diffusion

Mike Qittera
Hi,

I am trying to solve this problem too. Could you please share your solution.
Thanks.
Mike
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Re: Solution of Fick's law with concentration dependent diffusion

tkdiff
Sure.  TKdiff4.fea solves the non linear 1d diff equation with constant surface concentration using internal solvers.  TKdiff4_fenics.fea solves the same one using fenics.  I have a version that calculates a deposition, then a drive redistribution from the dep result, but it is an m file and needs the registered version of FEATool.
Tom

tkdiff4.featkdiff4_fenics.fea