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Modelling of special surface

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Hello,

In my research, I have a very weird surface to be modeled. I don't know how.
You can see in the picture attached. It is a spherical surface with the teeth in the form of circular cone.

What one can help me?

Sincerely,

Toan


4 Replies Last Post 21 mar 2011, 05:49 GMT-4

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Posted: 1 decade ago 16 mar 2011, 13:05 GMT-4
start by defining a cone with its base at the origin. The cone height will be the radius of the sphere + the height of the tooth. The angle of the cone will be defined be the angle the cone surface forms with its axis of symmetry. The radius will need to be calculated based on this information.

Once you know the dimensions of the cone required, create several of them at different angles by specifing the Axis direction vector using the spherical coordinate system.

Now you should have all your teeth in place, add a sphere to the model of appropriate radius.

Next you will need to make a composite object. Select a cone and the sphere and click the 'union' button then apply. Repeat this for all the cones.

See the attached image
start by defining a cone with its base at the origin. The cone height will be the radius of the sphere + the height of the tooth. The angle of the cone will be defined be the angle the cone surface forms with its axis of symmetry. The radius will need to be calculated based on this information. Once you know the dimensions of the cone required, create several of them at different angles by specifing the Axis direction vector using the spherical coordinate system. Now you should have all your teeth in place, add a sphere to the model of appropriate radius. Next you will need to make a composite object. Select a cone and the sphere and click the 'union' button then apply. Repeat this for all the cones. See the attached image


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Posted: 1 decade ago 16 mar 2011, 13:07 GMT-4
sorry, incase you don't like png, here's a jpg
sorry, incase you don't like png, here's a jpg


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

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Posted: 1 decade ago 16 mar 2011, 13:09 GMT-4
Hello

we have done similar things, that is >700 different cylinders attached to a sphere. We were lucky that we could use symmetry, so we constructed only 1/8 of a sphere and then added the others by mirror symmetry. It worked fine, took some time though to set up all the rotations correctly. But the model became rather heavy, typically 3-5 minutes refresh between each mouse click.

You can also construct it in a CAD tool and import 1/8th and then mirror the parts in COMSOL.

often its worth to have a clean part = sphere " nicely attached smaller items, specially with a clean boundary that is geometrical clean = no small edges, gaps of silver faces

--
Good luck
Ivar
Hello we have done similar things, that is >700 different cylinders attached to a sphere. We were lucky that we could use symmetry, so we constructed only 1/8 of a sphere and then added the others by mirror symmetry. It worked fine, took some time though to set up all the rotations correctly. But the model became rather heavy, typically 3-5 minutes refresh between each mouse click. You can also construct it in a CAD tool and import 1/8th and then mirror the parts in COMSOL. often its worth to have a clean part = sphere " nicely attached smaller items, specially with a clean boundary that is geometrical clean = no small edges, gaps of silver faces -- Good luck Ivar

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Posted: 1 decade ago 21 mar 2011, 05:49 GMT-4
Thank you very much.
I will try with your suggestions.

Sincerely,

Toan
Thank you very much. I will try with your suggestions. Sincerely, Toan

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