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Re: problem in apply the numerical flux in PDE
Posted 4 oct. 2013, 07:23 UTC−4 Results & Visualization Version 3.5a 6 Replies
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(This discussion refers to paper in www.comsol.com/paper/3d-simulation-of-action-potential-propagation-in-a-squid-giant-axon-7317)
Perhaps I'm mistaken, but I think that there is an error in the paper.
For me, it would be better to include
, i.e. let it as it comes by default, and
(this as there's no laplacian term for 
).And I would change F (the source term), to the rest of terms in equations (1) and (2):
, and
.If one does what authors say in equations (4) and (5), all those terms would be affected by the divergence operator (acting on
), and that's not possible (as they are scalars, not vectors, and the result, if possible, would be different from what appears in equations (1) and (2)).Regards,
Jesus.
Hello Jesus Lucio
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Thanks
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I understand from the article that
in equation (1) is the same as 
in eq. (8). Both physics (PDE Mode, for eqs. (1) and (2), and electrostatics, eq. (8)), seem to be solved simultaneously.Please login with a confirmed email address before reporting spam
Thanks.
Attachments:
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What would be the unit of the source term (F)? I've selected the unit of the dependent variables u1 and u2 as volts (V). Is that fine?
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Thanks
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i have same problem with simulation of this paper.
i don't know where the Γ would be applied:
Γ = Δu1 +(α − u1 )(u1 −1 )u1 +( −u2 )+I
Γ = ε(βu1 − γu2 − δ)
also my model has this errors in final :
Error:
Failed to find consistent initial values.
Undefined_value_found_Linsolv
NaN_or_Inf_found_when_solving_linear_system_using_SOR
Last time step is not converged.
please help me.