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Global constraint

Posted 2013年3月18日 GMT-4 15:12 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 2013年3月19日 GMT-4 02:49
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago 2013年3月18日 GMT-4 16:37
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 2013年3月19日 GMT-4 02:49
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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