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Mesh problem

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Hi

I'm building this geometry and im trying to build the mesh for this.
The model's big so ive used swept meshes to reduce the no of elements.
The error says inverted element!

I want to keep the no of elements to within 1 million to solve on a 16 GB system.

The default size is 1250 micrometer based on the minumum wavelength/6.
Been struggling with this for quite some time.

Any kind of help would be greatly appreciated.
Ive attached the model in this post.

Regards
Glenston


2 Replies Last Post Mar 28, 2012, 1:49 a.m. EDT

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Posted: 1 decade ago Mar 27, 2012, 5:25 p.m. EDT
The problem in meshing is very thin spiral layer. You can't create any reasonable mesh if you want to stay below 1M DoF. I'd suggest replacing it with zero-thickness boundary layer. Then it becomes very easy to mesh.
The problem in meshing is very thin spiral layer. You can't create any reasonable mesh if you want to stay below 1M DoF. I'd suggest replacing it with zero-thickness boundary layer. Then it becomes very easy to mesh.

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Posted: 1 decade ago Mar 28, 2012, 1:49 a.m. EDT

The problem in meshing is very thin spiral layer. You can't create any reasonable mesh if you want to stay below 1M DoF. I'd suggest replacing it with zero-thickness boundary layer. Then it becomes very easy to mesh.


Hi alexander

Thanks alot for your reply.
The geometry must be replaced by a zero thickness boundary layer?
I want my no of elements to stay below 1M not the degrees of freedom!

There is also a funny thing that occurs mapped2 and swept2 is for domain 7(one arm of the spiral) while mapped1 and swept1 is for domain 8(the other arm of the spiral. When you disable mapped2 and swept2 the mesh is created for domain 8.

This is strange as both domain 7 and 8 which are 2 arms of the spirals are identical to each other!!!
I wonder why this is happening.

It would be great if you could help me on this front!

Thanks a lot !

Regards
Glenston
[QUOTE] The problem in meshing is very thin spiral layer. You can't create any reasonable mesh if you want to stay below 1M DoF. I'd suggest replacing it with zero-thickness boundary layer. Then it becomes very easy to mesh. [/QUOTE] Hi alexander Thanks alot for your reply. The geometry must be replaced by a zero thickness boundary layer? I want my no of elements to stay below 1M not the degrees of freedom! There is also a funny thing that occurs mapped2 and swept2 is for domain 7(one arm of the spiral) while mapped1 and swept1 is for domain 8(the other arm of the spiral. When you disable mapped2 and swept2 the mesh is created for domain 8. This is strange as both domain 7 and 8 which are 2 arms of the spirals are identical to each other!!! I wonder why this is happening. It would be great if you could help me on this front! Thanks a lot ! Regards Glenston

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