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Natural convection in vertical tube

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Old   November 4, 2005, 05:49
Default Natural convection in vertical tube
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Ravi
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why do we get the message "non-positive area exists" when we do grid check in fluent. I've created an uniform mesh of 1 cm spacing in a rectangular area of 0.2 by 1 m. what to do when this message comes? anyone please help me.
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Old   November 4, 2005, 10:22
Default Re: Natural convection in vertical tube
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Jeremy
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Did you use Gambit to create the mesh? Is this a 2D or 3D case?

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Old   November 5, 2005, 04:41
Default Re: Natural convection in vertical tube
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Ravi
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Yes i used GAMBIT for meshing. it is 2D case.
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Old   November 7, 2005, 11:28
Default Re: Natural convection in vertical tube
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Jeremy
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Ok, there is not a lot of info to go by here. Did you check the grid quality as well in Gambit?

The "non-positive area" can occur during meshing when the meshing scheme ends up causing cell boundaries to cross. I have seen this happen in highly curved surfaces when using a boundary layer. But you seem to have a very simple case.

Is this an axisymmetrical domain?
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