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Use of the "IF" Operator in a Diffusion model
Posted Mar 21, 2012, 6:09 a.m. EDT Chemical Reaction Engineering, Parameters, Variables, & Functions, Studies & Solvers Version 4.2a 1 Reply
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Greetings!
I am simulating the diffusion of water into a paint film and want to define a maximum concentration.
I guess that I can do that by the operator "IF(c_H2O ,X ,X ,c_H2O)"
as I want the concentration to rise until it reaches the maximum value.
However I don't know where I have to put the operator.
I have also tried to define a variable with the operator as expression, but it will not show up in the results.
I hope you can help me. Thanks!
I am simulating the diffusion of water into a paint film and want to define a maximum concentration.
I guess that I can do that by the operator "IF(c_H2O ,X ,X ,c_H2O)"
as I want the concentration to rise until it reaches the maximum value.
However I don't know where I have to put the operator.
I have also tried to define a variable with the operator as expression, but it will not show up in the results.
I hope you can help me. Thanks!
1 Reply Last Post Mar 21, 2012, 2:14 p.m. EDT
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Posted:
1 decade ago
Hi
I'm not sure I catch you fully there, if you want to saturate a BC, use rather a step function, but if you want to ensure that your dependent variale in your domain is saturating, you need to tweak the equations or the material properties such that you saurate the solution. Your concentration, as solution is driven by the equations, and not the other way around, sofor me, you must attack the problem on the driver side, i.e. BC or materials ,or directly the equations
--
Good luck
Ivar
I'm not sure I catch you fully there, if you want to saturate a BC, use rather a step function, but if you want to ensure that your dependent variale in your domain is saturating, you need to tweak the equations or the material properties such that you saurate the solution. Your concentration, as solution is driven by the equations, and not the other way around, sofor me, you must attack the problem on the driver side, i.e. BC or materials ,or directly the equations
--
Good luck
Ivar