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Global constraint

Posted Mar 18, 2013, 3:12 p.m. EDT Version 4.3a 2 Replies

Morten Hygum
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Hi,

I am modelling thermodiffusion of moisture with the mathematical module. Is it possible impose a constraint to the concentration, c, in order to ensure it stays positive.
2 Replies Last Post Mar 19, 2013, 2:49 a.m. EDT
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago Mar 18, 2013, 4:37 p.m. EDT
A negative concentration is frequently a sign of an incorrectly defined physics, coarse mesh or large time steps in a transient analysis. In general you don’t need a constraint to enforce the concentration to stay non-negative.

Nagi Elabbasi
Veryst Engineering
A negative concentration is frequently a sign of an incorrectly defined physics, coarse mesh or large time steps in a transient analysis. In general you don’t need a constraint to enforce the concentration to stay non-negative. Nagi Elabbasi Veryst Engineering
Morten Hygum
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Posted: 1 decade ago Mar 19, 2013, 2:49 a.m. EDT
Thank you for your response.

I am not using using the bulit-in modules. I needed to use the math module.
Thank you for your response. I am not using using the bulit-in modules. I needed to use the math module.

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