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Magnetic Fields are not solved within specific domains

Posted Sep 25, 2024, 7:57 p.m. EDT Modeling Workflow 4 Replies

Maruthi Annamaraju
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Hi,

I am trying to do a magnetohydrodynamics problem (fluids, magnetic fields, heat transfer) along with a non-isothermal flow in an induction furnace problem. Right now I am trying to figure out the coupling between magnetic field and fluids, and plan to eventually build to coupling between all three fields (magneto-thermo-hydrodynamic model of a liquid metal system).

However, I am observing that the magnetic field is not being solved for fluids domain and coil domain, due to which fluid flow is also not occurring. I have attached my file (Run on a linux system) here:

4 Replies Last Post Sep 26, 2024, 2:08 p.m. EDT
Maruthi Annamaraju
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Posted: 6 months ago Sep 25, 2024, 8:02 p.m. EDT

Hi, I am trying to reduce file size but it is not going below 110 MB even after clearing mesh and optimizing for file size. Please let me know if there is any other way.

Alternately, this is what is happening. The magnetic field lines are "avoiding" liquid metal domain, coil, and water in the coil. I have set relative permeability and permittivity to 1 for all the domains. It looks like the attached pdf.

Please let me know if there is any way to debug this. Any help is appreciated.

Thank you! Maruthi

Hi, I am trying to reduce file size but it is not going below 110 MB even after clearing mesh and optimizing for file size. Please let me know if there is any other way. Alternately, this is what is happening. The magnetic field lines are "avoiding" liquid metal domain, coil, and water in the coil. I have set relative permeability and permittivity to 1 for all the domains. It looks like the attached pdf. Please let me know if there is any way to debug this. Any help is appreciated. Thank you! Maruthi

Attachments:

Edgar J. Kaiser Certified Consultant
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Posted: 6 months ago Sep 26, 2024, 3:09 a.m. EDT

Maruthi,

to shrink the file it is essential to clear the solution too. The picture looks like some domains are not included in the mf physics.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Maruthi, to shrink the file it is essential to clear the solution too. The picture looks like some domains are not included in the mf physics. Cheers Edgar
Maruthi Annamaraju
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Posted: 6 months ago Sep 26, 2024, 1:41 p.m. EDT

Hey,

I checked once again. I have domains listed in the magnetic field physics tab. I have liquid part in "Amperes law of fluids", coil in the "Coil 1" and the furnace in the "Amperes law of Solids". I am attaching the file here after removing meshes and solutions but the field still looks like the attached pdf.

Hey, I checked once again. I have domains listed in the magnetic field physics tab. I have liquid part in "Amperes law of fluids", coil in the "Coil 1" and the furnace in the "Amperes law of Solids". I am attaching the file here after removing meshes and solutions but the field still looks like the attached pdf.

Attachments:

Edgar J. Kaiser Certified Consultant
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Posted: 6 months ago Sep 26, 2024, 2:08 p.m. EDT

I think the model is ok. Inconel and Copper have high electrical conductivity, so the skin effect keeps current and fields in a thin layer at the surfaces. If you zoom into the plot you see it in the Inconel. You need a much finer mesh to resolve the skin effect at the metallic surfaces. I recommend boundary layers with a layer thickness of 1/5 of the respective skin depth at your frequency.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
I think the model is ok. Inconel and Copper have high electrical conductivity, so the skin effect keeps current and fields in a thin layer at the surfaces. If you zoom into the plot you see it in the Inconel. You need a much finer mesh to resolve the skin effect at the metallic surfaces. I recommend boundary layers with a layer thickness of 1/5 of the respective skin depth at your frequency. Cheers Edgar

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