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When I have to use 2d or 3d modeling?

Wagner Gurgel do Amaral Filho

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Hi Everybody!

I´m Wagner, from Brazil and I have a question, a simple question I think!
How I decide if my modeling will be in 2d or in 3d?
I have Heat Transfer and AC/DC model and I work calculating and projecting Electrical Equipament, like Transformers, Reactor, Harmonic Filters and more...
Someone here have this knowledge?

Thank you for your time.

Best Regards,

Wagner.

2 Replies Last Post 20.01.2013, 16:38 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 17.01.2013, 08:59 GMT-5
Hi

first of all, 2D is far "easier" = lighter w.r.t. RAM and resources, hence solves much faster. But 2D or 2D-axi means that you model have given plane or axial cylindrical symmetry. This is not always the case, so it all depends.

my way is to start as far as possible with simple 2D or 2D-axi models. Once these work I go to full 3D models and only if I really need to

--
Good luck
Ivar
Hi first of all, 2D is far "easier" = lighter w.r.t. RAM and resources, hence solves much faster. But 2D or 2D-axi means that you model have given plane or axial cylindrical symmetry. This is not always the case, so it all depends. my way is to start as far as possible with simple 2D or 2D-axi models. Once these work I go to full 3D models and only if I really need to -- Good luck Ivar

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Posted: 1 decade ago 20.01.2013, 16:38 GMT-5
Hi
generally you can neglect any direction in situations when there is no heat flux in this particular direction, in other words there is no significant temperature difference or gradient in this direction. Typical is cylindrical symmetry but only when there is no "azimutal" change (for example one half of the cylinder is heated the other side cooled). And when the cylinder is very long, probably the heat flux in the axial direction can be neglected, because the thermal resistance in this direction is so large that it does not allow any heat to flow in this direction. So it sometimes a trade off and a matter of simplification.
Miro
Hi generally you can neglect any direction in situations when there is no heat flux in this particular direction, in other words there is no significant temperature difference or gradient in this direction. Typical is cylindrical symmetry but only when there is no "azimutal" change (for example one half of the cylinder is heated the other side cooled). And when the cylinder is very long, probably the heat flux in the axial direction can be neglected, because the thermal resistance in this direction is so large that it does not allow any heat to flow in this direction. So it sometimes a trade off and a matter of simplification. Miro

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