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3-D Oxygen permeation model
Posted 01.05.2014, 14:28 GMT-4 Chemical Reaction Engineering Version 4.3b 2 Replies
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Hi,
i'm a Master after Master Program student and i'm trying to solve a problem concerning the permeation of oxygen in a 3-D object where i have an internal gas headspace ("Transport of species concentrated)and other internal water domain(Trassport in species diluited")
The external domains are plastics modelled with a "Flow in porous media".
Now i have set all the model but i have a warning with the geometry imported to CAD model. I have an edge smaller the minimum dimension (also with Extra fine).
Now i found this error:
"Very ill conditioned preconditioner: The relative residual is more than 1000 times larger than the relative tolerance.
What's the problem??Depend on the geometry warning How i could set the solver??
Thanks in advance
i'm a Master after Master Program student and i'm trying to solve a problem concerning the permeation of oxygen in a 3-D object where i have an internal gas headspace ("Transport of species concentrated)and other internal water domain(Trassport in species diluited")
The external domains are plastics modelled with a "Flow in porous media".
Now i have set all the model but i have a warning with the geometry imported to CAD model. I have an edge smaller the minimum dimension (also with Extra fine).
Now i found this error:
"Very ill conditioned preconditioner: The relative residual is more than 1000 times larger than the relative tolerance.
What's the problem??Depend on the geometry warning How i could set the solver??
Thanks in advance
2 Replies Last Post 01.05.2014, 17:35 GMT-4
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Posted:
1 decade ago
Mario:
It would be useful if you can give us a more detailed description of your model and your solver settings or if you can give us your model file.
Srivatsava
It would be useful if you can give us a more detailed description of your model and your solver settings or if you can give us your model file.
Srivatsava
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Posted:
1 decade ago
Unfortunately the file is too large so i can't attach it.
I hadn't changed the solver parameters but maybe if i changed them i would start the simulation.
So i ask you if changing these parameters like tolerance ecc. i could remove this error.
The model must explain the oxigen permeation through plastic film and then gas and liquid (water).
Like boundary conditions i fixed the continuity ( like pair) in internal domains and on external faces the oxigen ambient concentration.
I hadn't changed the solver parameters but maybe if i changed them i would start the simulation.
So i ask you if changing these parameters like tolerance ecc. i could remove this error.
The model must explain the oxigen permeation through plastic film and then gas and liquid (water).
Like boundary conditions i fixed the continuity ( like pair) in internal domains and on external faces the oxigen ambient concentration.