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Imposing Divergence Free Constraint on Magnetic Field in COMSOL

Ananth Saran Yalamarthy

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Hi there,
I'm using the AC/DC module to solve for the magnetic field due to a current loop. I'm solving it by imposing an external current density in the 2-D Axisymmetric Formulation. Once the study is complete, I am importing the components of the magnetic field to a text file and using this data for a plasma simulation code.

My plasma simulation code needs del.B=0 to be obeyed as precisely as possible. Is there a way to impose the del.B=0 constraint? (i'm assming that it is already imposed, but I can't see it as an equation under the Ampere's Law tab). Is there a way to reduce the error using a technique other than reducing the mesh size?

Thank you!

Ananth

3 Replies Last Post 30 mar 2014, 09:45 GMT-4
Edgar J. Kaiser Certified Consultant

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Posted: 1 decade ago 30 mar 2014, 08:17 GMT-4
Ananth,

you probably mean div B = 0. This is warranted by B = rot A and thus div B = div rot A = 0.

Instead of refining the mesh you can try higher order elements.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Ananth, you probably mean div B = 0. This is warranted by B = rot A and thus div B = div rot A = 0. Instead of refining the mesh you can try higher order elements. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com

Ananth Saran Yalamarthy

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Posted: 1 decade ago 30 mar 2014, 09:08 GMT-4
Dear Edgar,

Thanks for the reply! I tried searching for how to use higher order elements in 2D but couldn't find anything. Could you kindly clarify?

Thank you very much.

Sincerely,
Ananth
Dear Edgar, Thanks for the reply! I tried searching for how to use higher order elements in 2D but couldn't find anything. Could you kindly clarify? Thank you very much. Sincerely, Ananth

Edgar J. Kaiser Certified Consultant

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Posted: 1 decade ago 30 mar 2014, 09:45 GMT-4

You can set it in the 'Component' node

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
You can set it in the 'Component' node -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com

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