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Meshing
Posted Nov 30, 2015, 12:01 p.m. EST Low-Frequency Electromagnetics, Mesh Version 5.1 2 Replies
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Dear Comsol Users,
how I can make meshing for tow parts, they are cylinders, but one of both is too big In comparison with other one.
the first Cylinder R: 16 mm Hight: 10000 mm the other one R: 30000 mm, Hight: 60000 mm.
If any one know how I can make this meching, I well have pleasure if anyone could to help me.
I face always as this messages:
1-Edge is much shorter than the specified minimum element size
2-Face is (or has a narrow region that is) much smaller than the specified minimum element size.
Regards
how I can make meshing for tow parts, they are cylinders, but one of both is too big In comparison with other one.
the first Cylinder R: 16 mm Hight: 10000 mm the other one R: 30000 mm, Hight: 60000 mm.
If any one know how I can make this meching, I well have pleasure if anyone could to help me.
I face always as this messages:
1-Edge is much shorter than the specified minimum element size
2-Face is (or has a narrow region that is) much smaller than the specified minimum element size.
Regards
2 Replies Last Post Dec 3, 2015, 11:11 a.m. EST
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Posted:
9 years ago
Hi,
I often say that meshing is more an art than science (by the way you might try a search on that you could be able to dig out some of my older chats on this subject).
For your case I see mainly 2 issues:
a) either your two cylinders intersect someway, then the transition, from a small fine mesh on the small cylinder, to the larger cylinder is probably too big, so the mesher algorithm has some issues to link both meshes
b) they do not intersect, in which case I suggest that you mesh one sections of each and use a sweep mesh for the length, with not too many elements.
in the case a) there are a few tricks: one is to add another cylinder of intermittent size, and mesh the smaller one, then the middle one and finally the outer one, with different sizes. the other way is to mesh element by element and try out different settings until you get it OK. Do not forget that the mesh density should be such that your dependent variables are well resolves, including their slopes (first derivatives)
You have a few videos and a few very detailed blogs on the most common meshing issues, I suggest that you search furter the COMSOL blogs and then the videos and the Forum :)
--
Good luck
Ivar
I often say that meshing is more an art than science (by the way you might try a search on that you could be able to dig out some of my older chats on this subject).
For your case I see mainly 2 issues:
a) either your two cylinders intersect someway, then the transition, from a small fine mesh on the small cylinder, to the larger cylinder is probably too big, so the mesher algorithm has some issues to link both meshes
b) they do not intersect, in which case I suggest that you mesh one sections of each and use a sweep mesh for the length, with not too many elements.
in the case a) there are a few tricks: one is to add another cylinder of intermittent size, and mesh the smaller one, then the middle one and finally the outer one, with different sizes. the other way is to mesh element by element and try out different settings until you get it OK. Do not forget that the mesh density should be such that your dependent variables are well resolves, including their slopes (first derivatives)
You have a few videos and a few very detailed blogs on the most common meshing issues, I suggest that you search furter the COMSOL blogs and then the videos and the Forum :)
--
Good luck
Ivar
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Posted:
9 years ago
Dear ivar,
thank you very much for your Reply,
I will tray to do that. Actualy my Model is more difcult as i said.
My model consist of many parts of small Cylinders and only one of them is too big.
With my Regards
Maher
thank you very much for your Reply,
I will tray to do that. Actualy my Model is more difcult as i said.
My model consist of many parts of small Cylinders and only one of them is too big.
With my Regards
Maher