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Swept mesh singular matrix error

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Hello,

I have a 3D model and I am trying to mesh is with brick elements. I break up the model into small volumes (thank you Ivar), and then I use mapped mesh followed by the swept mesh. I am able to mesh it with bricks, however, when I try to solve the problem, it gives me the same error over and over - singular matrix. When I use free mesh or swept mesh with triangular elements at the source and target faces, it solves the problem.

Would anyone know why this happens?

Thank you

3 Replies Last Post Sep 30, 2010, 2:24 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jul 15, 2010, 11:29 a.m. EDT
Hi

I'm not sure it's linked to the mesh. Are you sure that you do not have some missing BC's ?
Try to mesh it coarse with thets and check if your initial conditions are chorent
Good luck
Ivar
Hi I'm not sure it's linked to the mesh. Are you sure that you do not have some missing BC's ? Try to mesh it coarse with thets and check if your initial conditions are chorent Good luck Ivar

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Posted: 1 decade ago Jul 16, 2010, 6:17 a.m. EDT
Hi,

I think poor mesh quality could cause the Singular Matrix error. Check the "Minimum elemental quality" in Mesh Statistics. If it is less than 0.005, it might be a low quality mesh.


AndyT
Hi, I think poor mesh quality could cause the Singular Matrix error. Check the "Minimum elemental quality" in Mesh Statistics. If it is less than 0.005, it might be a low quality mesh. AndyT

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Posted: 1 decade ago Sep 30, 2010, 2:24 a.m. EDT
I confirm that almost all problems with singular matrix that is the problem of bad or not quality mesh of some parts of the assambly. Try to make better your meshing in the active (or most active) parts.
I confirm that almost all problems with singular matrix that is the problem of bad or not quality mesh of some parts of the assambly. Try to make better your meshing in the active (or most active) parts.

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