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Free tethedral mesh problem for thin plates

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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 12 nov 2014, 02:54 GMT-5
Robert Koslover Certified Consultant

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Posted: 1 decade ago 7 nov 2014, 22:50 GMT-5
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.

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Posted: 1 decade ago 8 nov 2014, 19:39 GMT-5
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 ?

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Posted: 1 decade ago 10 nov 2014, 03:32 GMT-5

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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Posted: 1 decade ago 11 nov 2014, 07:22 GMT-5
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.

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Posted: 1 decade ago 11 nov 2014, 07:22 GMT-5
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.

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Posted: 1 decade ago 12 nov 2014, 02:54 GMT-5
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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