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3D spherical dome composites - meshing problem

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Hi,

I've spent a full day trying to mesh that thing but to no avail.

Maybe you would have any hints or tricks to help me?

I've tried different methods (mapped surfaces with edges, converting to triangle, etc.) but I always end up with degenerated thets...

My ONLY requirement for my mesh is to get 2-3 elements thick in each ply/layer in order to capture the transmitted stress adequately.

I included my working file but of course, I cleaned up the mesh...

Any hints or comments would be welcome. I first started using mapped mesh on the flat boundaries but since the big surfaces only have 3 edges, they cannot be meshed with quads.

It's a very simple geometry but seems hard to mesh at all!
(It's actually one quarter of the full geometry)

Thanks in advance for any help,
Dominique


3 Replies Last Post 25 févr. 2011, 11:16 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 24 févr. 2011, 18:38 UTC−5
Hi

I turned back to physics controlled mesh and set it to normal, and it meshed in less than a minutes, but with about 1M elements and 5 times as many DoFs, that was too big for my WS.
Setting to extremely coarse I get a reasonnable mesh quality and it solves partly with about 8-28Gb of ram in >1000 secs. But it looks like it' diverging after some time. Are you sure you got the distributed E modulus correct ?

--
Good luck
Ivar
Hi I turned back to physics controlled mesh and set it to normal, and it meshed in less than a minutes, but with about 1M elements and 5 times as many DoFs, that was too big for my WS. Setting to extremely coarse I get a reasonnable mesh quality and it solves partly with about 8-28Gb of ram in >1000 secs. But it looks like it' diverging after some time. Are you sure you got the distributed E modulus correct ? -- Good luck Ivar

Magnus Ringh COMSOL Employee

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Posted: 1 decade ago 25 févr. 2011, 05:07 UTC−5
Hi,

The easiest way to quickly mesh a layered geometry like this with control of the number of mesh elements in each layer is to use a Swept mesh:

- Right-click an empty Mesh node and select Swept.
- In the Settings window for the Swept node, select "Triangular (Generate prisms)" from the "Face meshing method" list in the "Sweep Method" section. The default "Quadrilateral (Generate hexahedrons)" settings doesn't work for this singular geometry.
- Right-click the Swept node and select Distribution.
- In the Settings window for the Distribution node, all domains should be selected by default. Type 3 (for example) in the "Number of elements" edit field to create 3 mesh element layers in each geometry layer.
- Click the "Build All" button or press F8 to create the mesh.

You can add additional nodes and settings to control the mesh density on the surfaces, and so on.

Best regards,
Magnus Ringh, COMSOL
Hi, The easiest way to quickly mesh a layered geometry like this with control of the number of mesh elements in each layer is to use a Swept mesh: - Right-click an empty Mesh node and select Swept. - In the Settings window for the Swept node, select "Triangular (Generate prisms)" from the "Face meshing method" list in the "Sweep Method" section. The default "Quadrilateral (Generate hexahedrons)" settings doesn't work for this singular geometry. - Right-click the Swept node and select Distribution. - In the Settings window for the Distribution node, all domains should be selected by default. Type 3 (for example) in the "Number of elements" edit field to create 3 mesh element layers in each geometry layer. - Click the "Build All" button or press F8 to create the mesh. You can add additional nodes and settings to control the mesh density on the surfaces, and so on. Best regards, Magnus Ringh, COMSOL

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 25 févr. 2011, 11:16 UTC−5
Hi Magnus

Indeed it worked fine, apart of a resulting rather poor mesh quality but this is difficult to avoid with such aspect ratios it meshes easily

Still for me it solves slowly, point loads are not the nicest for convergence

--
Good luck
Ivar
Hi Magnus Indeed it worked fine, apart of a resulting rather poor mesh quality but this is difficult to avoid with such aspect ratios it meshes easily Still for me it solves slowly, point loads are not the nicest for convergence -- Good luck Ivar

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