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how to mesh a 3D closed rotating object with an irregular surface

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hi,

I have a model that looks like a torus, however, the rotating surface is an irregular polygon.
At first, i cut into two pieces and mesh only half of the model.So I can select the cross section(the rotating surface) as the swept surface, and it swepts very well.
Now i want to swept the whole model,but i cannot select the cross section because it's a closed rotating object and don't have any cross section to select.
Does anybody have some suggestions?

7 Replies Last Post Jun 13, 2012, 2:42 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 Jun 11, 2012, 12:46 a.m. EDT
Hi

cut your model into 2 halves, or generate it by 2 rotations of 180° that is from my experience the easiest

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Good luck
Ivar
Hi cut your model into 2 halves, or generate it by 2 rotations of 180° that is from my experience the easiest -- Good luck Ivar

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Posted: 1 decade ago Jun 11, 2012, 9:32 a.m. EDT
hi,thanks

I don't know how to cut. I try to cut it use a very thin extrude and then difference. Finally. there will be a gap between the two parts. Can I use identity pair to connect the two parts. I try to find a way to just cut it without any gap between two parts

thanks a lot

zhengui
hi,thanks I don't know how to cut. I try to cut it use a very thin extrude and then difference. Finally. there will be a gap between the two parts. Can I use identity pair to connect the two parts. I try to find a way to just cut it without any gap between two parts thanks a lot zhengui

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

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Posted: 1 decade ago Jun 11, 2012, 11:11 a.m. EDT
Hi

try to avoid small gaps. You can cut by making a workplane with a rectangle or a circle at the dimensions of you shadow, but you do not need to extrude it, it makes a "thin" surface of "0" thickness, and in union mode your geometry should be cut that way

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Good luck
Ivar
Hi try to avoid small gaps. You can cut by making a workplane with a rectangle or a circle at the dimensions of you shadow, but you do not need to extrude it, it makes a "thin" surface of "0" thickness, and in union mode your geometry should be cut that way -- Good luck Ivar

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Posted: 1 decade ago Jun 11, 2012, 12:44 p.m. EDT
hi, thanks very much

I follow your suggestions, however, I failed to form union after I draw a rectangle in a workplane: "error,boolean geometry operation failed".

I can form assembly but the torus is still one domain. In another word, I didn't cut it into two parts.

In fact, I need to form assmely rather then union because my entire model includes four parts. I should treat the four parts seperately.

thanks your help very much


zhengui
hi, thanks very much I follow your suggestions, however, I failed to form union after I draw a rectangle in a workplane: "error,boolean geometry operation failed". I can form assembly but the torus is still one domain. In another word, I didn't cut it into two parts. In fact, I need to form assmely rather then union because my entire model includes four parts. I should treat the four parts seperately. thanks your help very much zhengui

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

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Posted: 1 decade ago Jun 11, 2012, 2:40 p.m. EDT
Hi

I would suggest that you check the doc again and test it out on simple rectangles, cutting domains does work with workplanes and surfaces drawn on the workplane, If you extrude they get a thickness, if not they remain thin surfaces

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Good luck
Ivar
Hi I would suggest that you check the doc again and test it out on simple rectangles, cutting domains does work with workplanes and surfaces drawn on the workplane, If you extrude they get a thickness, if not they remain thin surfaces -- Good luck Ivar

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Posted: 1 decade ago Jun 12, 2012, 12:51 p.m. EDT
hi, Ivar,

thanks for your kind reply.

hi, Ivar, thanks for your kind reply.

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

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Posted: 1 decade ago Jun 13, 2012, 2:42 a.m. EDT
Hi

you need to reload your files, probably the server was saturated, when we download them they say "0" bytes ;)

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Good luck
Ivar
Hi you need to reload your files, probably the server was saturated, when we download them they say "0" bytes ;) -- Good luck Ivar

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