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total flux condition

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Hi everybody,
Does anybody know how to introduce the Robin condition (total flux condition) for the chemical species transport module?
Thanks,
Joana.

2 Replies Last Post 22 janv. 2014, 09:21 UTC−5

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Posted: 1 decade ago 21 janv. 2014, 03:58 UTC−5

Hi everybody,
Does anybody know how to introduce the Robin condition (total flux condition) for the chemical species transport module?
Thanks,
Joana.


Hi

Robin condition:

a*c + b*grad(c) = g <=> c = A*grad(c) + B

Hence, use the concentration boundary condition by writing in the concentration box (3D case)

A*(cx+cy+cz) + B

and define A and B in the parameters list. I tried this in 1D and it worked fine.

BR
Lasse
[QUOTE] Hi everybody, Does anybody know how to introduce the Robin condition (total flux condition) for the chemical species transport module? Thanks, Joana. [/QUOTE] Hi Robin condition: a*c + b*grad(c) = g c = A*grad(c) + B Hence, use the concentration boundary condition by writing in the concentration box (3D case) A*(cx+cy+cz) + B and define A and B in the parameters list. I tried this in 1D and it worked fine. BR Lasse

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 22 janv. 2014, 09:21 UTC−5


Hi everybody,
Does anybody know how to introduce the Robin condition (total flux condition) for the chemical species transport module?
Thanks,
Joana.


Hi

Robin condition:

a*c + b*grad(c) = g <=> c = A*grad(c) + B

Hence, use the concentration boundary condition by writing in the concentration box (3D case)

A*(cx+cy+cz) + B

and define A and B in the parameters list. I tried this in 1D and it worked fine.

BR
Lasse


Thanks, the problem is already solved.

Joana.

[QUOTE] [QUOTE] Hi everybody, Does anybody know how to introduce the Robin condition (total flux condition) for the chemical species transport module? Thanks, Joana. [/QUOTE] Hi Robin condition: a*c + b*grad(c) = g c = A*grad(c) + B Hence, use the concentration boundary condition by writing in the concentration box (3D case) A*(cx+cy+cz) + B and define A and B in the parameters list. I tried this in 1D and it worked fine. BR Lasse [/QUOTE] Thanks, the problem is already solved. Joana.

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