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Free tethedral mesh problem for thin plates

Posted Nov 7, 2014, 3:21 p.m. EST Mesh Version 4.3, Version 4.3b 6 Replies

Bahadir Sarikaya
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Hi everyone,

I want to mesh a thin plate with 0.1 um thickness and 820 x 820 um square. I used free tetrahedral mesh but my process always stop around %20 and doesn't proceed any more.

Do you have any idea about this problem ? or what should ı use ? (other methods, ways)
6 Replies Last Post Nov 12, 2014, 2:54 a.m. EST
Robert Koslover Certified Consultant
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Posted: 10 years ago Nov 7, 2014, 10:50 p.m. EST
Try scaling your mesh (where you set the params for free tetrahedral). For example, try setting x,y , and z scalings as 0.1, 0.1, and 1. 0 . Other similar arrangements may also work. Also, play with the normal vs finer etc. settings.
Try scaling your mesh (where you set the params for free tetrahedral). For example, try setting x,y , and z scalings as 0.1, 0.1, and 1. 0 . Other similar arrangements may also work. Also, play with the normal vs finer etc. settings.
Bahadir Sarikaya
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Posted: 10 years ago Nov 8, 2014, 7:39 p.m. EST
I apply your scaling suggestion, it works for mesh. However, then I started to compute my model and face an error like this :

"Failed to find a solution.
Singular matrix.

For mesh-case 0 there are 4784867 void equations (empty rows in matrix) for the variable mod1.V.
at coordinates: (-0.00048902,8.4856e-005,0.0004875), (-0.00048902,8.4606e-005,0.000489936), (-0.00048902,8.4356e-005,0.000492372), (-0.00048902,8.4356e-005,0.0004875), (-0.00048902,8.4106e-005,0.000489936), ...
and similarly for the degrees of freedom (empty columns in matrix).
Returned solution is not converged. "

Can it be related with meshing, or other model feature ?
I apply your scaling suggestion, it works for mesh. However, then I started to compute my model and face an error like this : "Failed to find a solution. Singular matrix. For mesh-case 0 there are 4784867 void equations (empty rows in matrix) for the variable mod1.V. at coordinates: (-0.00048902,8.4856e-005,0.0004875), (-0.00048902,8.4606e-005,0.000489936), (-0.00048902,8.4356e-005,0.000492372), (-0.00048902,8.4356e-005,0.0004875), (-0.00048902,8.4106e-005,0.000489936), ... and similarly for the degrees of freedom (empty columns in matrix). Returned solution is not converged. " Can it be related with meshing, or other model feature ?
Lasse Murtomäki
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Posted: 10 years ago Nov 10, 2014, 3:32 a.m. EST

Hi everyone,

I want to mesh a thin plate with 0.1 um thickness and 820 x 820 um square. I used free tetrahedral mesh but my process always stop around %20 and doesn't proceed any more.

Do you have any idea about this problem ? or what should ı use ? (other methods, ways)


Hi

Try Swept mesh. First mesh one 820 x 820 um face with free triangular elements. Then Swept mesh across 0.1 um. You can also refine the mesh in vertical direction adding a distribution with, say, 5 layers. Attached my model, but it is done in version 4.4.

best regards
Lasse
[QUOTE] Hi everyone, I want to mesh a thin plate with 0.1 um thickness and 820 x 820 um square. I used free tetrahedral mesh but my process always stop around %20 and doesn't proceed any more. Do you have any idea about this problem ? or what should ı use ? (other methods, ways) [/QUOTE] Hi Try Swept mesh. First mesh one 820 x 820 um face with free triangular elements. Then Swept mesh across 0.1 um. You can also refine the mesh in vertical direction adding a distribution with, say, 5 layers. Attached my model, but it is done in version 4.4. best regards Lasse

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Bahadir Sarikaya
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Posted: 10 years ago Nov 11, 2014, 7:22 a.m. EST
Hi,

Thank for your advise. But actually I have additional two different layers one on the top of the other and they have different geometry like rectangular. Should I apply swept mesh each other seperately or totaly?
Because I try to make swept mesh totaly but I got an error.

Before swept mesh, I tried with free tetrehedral mesh, my process always stop around %20 and doesn't proceed any more because of that 0.1um thickness 820x820 um square plate.

Hi, Thank for your advise. But actually I have additional two different layers one on the top of the other and they have different geometry like rectangular. Should I apply swept mesh each other seperately or totaly? Because I try to make swept mesh totaly but I got an error. Before swept mesh, I tried with free tetrehedral mesh, my process always stop around %20 and doesn't proceed any more because of that 0.1um thickness 820x820 um square plate.
Bahadir Sarikaya
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Posted: 10 years ago Nov 11, 2014, 7:22 a.m. EST
Hi,

Thank for your advise. But actually I have additional two different layers one on the top of the other and they have different geometry like rectangular. Should I apply swept mesh each other seperately or totaly?
Because I try to make swept mesh totaly but I got an error.

Before swept mesh, I tried with free tetrehedral mesh, my process always stop around %20 and doesn't proceed any more because of that 0.1um thickness 820x820 um square plate.

Hi, Thank for your advise. But actually I have additional two different layers one on the top of the other and they have different geometry like rectangular. Should I apply swept mesh each other seperately or totaly? Because I try to make swept mesh totaly but I got an error. Before swept mesh, I tried with free tetrehedral mesh, my process always stop around %20 and doesn't proceed any more because of that 0.1um thickness 820x820 um square plate.
Lasse Murtomäki
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Posted: 10 years ago Nov 12, 2014, 2:54 a.m. EST
If you submit your geometry I can try to mesh it.
If you submit your geometry I can try to mesh it.

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