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Old   April 9, 2009, 10:44
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hi guys

when I tryed to mesh the model in the picture, I always failed with the message "mesh of volume volume.1 contains 1 inverted elements(negative volume)".

I tryed everyway in the Gambit to mesh it and make the interval size smaller but the negative volumes only became more.

and the meshed model can't be checked right by the Fluent.

what should I do

thx in advance
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Old   April 9, 2009, 22:43
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and now I've found the negative volume

but what can I do to refine it?




help ,please
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Old   April 14, 2009, 03:12
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creat geometry in (+X, +Y) direction., Make sure that all your geometry is in positive 'X & Y' direction.
it may resolve your problem.
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Old   April 14, 2009, 04:09
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Quote:
Originally Posted by satheeskannan View Post
creat geometry in (+X, +Y) direction., Make sure that all your geometry is in positive 'X & Y' direction.
it may resolve your problem.
This trick may be only avalaible for 2d-axisymetric model

Perturb your mesh (with size function for instance) and check if the negative colume remains
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Old   April 14, 2009, 22:31
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thx very much you two

I can't wait until these excellent ideas come so that I used the commands splitting volume and setting interfaces.

the problem is solved, pretty good.
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Old   April 14, 2009, 22:36
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Quote:
Originally Posted by satheeskannan View Post
creat geometry in (+X, +Y) direction., Make sure that all your geometry is in positive 'X & Y' direction.
it may resolve your problem.

I think this method is simple and cool!
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Old   April 14, 2009, 22:39
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Originally Posted by -mAx- View Post
This trick may be only avalaible for 2d-axisymetric model

Perturb your mesh (with size function for instance) and check if the negative colume remains
hi sir,

can you tell me the method to perturb the mesh?

do I have to use UDFs?

thx
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Old   April 15, 2009, 00:46
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no UDF, just modify something in your mesh parameter ( or enforce the mesh to be refined somewhere with size-function)
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Old   April 15, 2009, 03:57
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no UDF, just modify something in your mesh parameter ( or enforce the mesh to be refined somewhere with size-function)

I can find the size-function in the 2-D panel such as MOVE FACE NODES/SPLIT QUAD MESH

but no such functions in 3-D panel

so where's the 3-D size-function? O(∩_∩)O~

thank you again
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Old   April 15, 2009, 04:03
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size functions are located at the same place (2d-3d)
In operation, click on the right button (the one with the blue tools)
In Tools, this is the second button from the left
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Old   April 15, 2009, 04:52
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size functions are located at the same place (2d-3d)
In operation, click on the right button (the one with the blue tools)
In Tools, this is the second button from the left

why didn't I find these excellent functions before?

thank you so much!
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