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Magnetic Field in Axisymmetric Model

Posted Nov 11, 2019, 11:06 a.m. EST Low-Frequency Electromagnetics Version 5.3a 3 Replies

Kate Richardson
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Hello,

I am having trouble seeing the correct results from a current in a loop of wire in an axisymmetric model. I am using the Magnetic Fields physics and I've tried adding either an External Current Density and a Line Current (Out-of-Plane) and see no magnetic field in the center of the loop from either. I've attached my model, any advice?

Thanks!

Attachments:

3 Replies Last Post Nov 12, 2019, 8:32 a.m. EST
Edgar J. Kaiser Certified Consultant
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Posted: 5 years ago Nov 11, 2019, 11:35 a.m. EST

Kate,

this is is probably a visualisation effect. The flux density close to the very thin wire or the line current is by orders of magnitude higher than in the rest of the air domain. So the scaling is not really appropriate to see details of the field. You can plot log10(mf.normB) to see what I mean. I also saw that you are setting µr for the water domain very close to zero where it should be 1?

Cheers Edgar

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Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Kate, this is is probably a visualisation effect. The flux density close to the very thin wire or the line current is by orders of magnitude higher than in the rest of the air domain. So the scaling is not really appropriate to see details of the field. You can plot log10(mf.normB) to see what I mean. I also saw that you are setting µr for the water domain very close to zero where it should be 1? Cheers Edgar
Kate Richardson
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Posted: 5 years ago Nov 11, 2019, 1:45 p.m. EST
Updated: 5 years ago Nov 11, 2019, 8:45 a.m. EST

Thanks, Edgar! Adding the log10 makes it a lot more clear. I was trying to simulate salt water instead of fresh water, but my university does not own a liscence to the Corrosion module so it is not a built in material. I found that value in a paper, but I will switch it to 1.

Thanks, Edgar! Adding the log10 makes it a lot more clear. I was trying to simulate salt water instead of fresh water, but my university does not own a liscence to the Corrosion module so it is not a built in material. I found that value in a paper, but I will switch it to 1.
Edgar J. Kaiser Certified Consultant
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Posted: 5 years ago Nov 12, 2019, 8:32 a.m. EST

Hi Kate,

you probably found the magnetic susceptibility which is often used for paramagnetic or diamagnetic materials:

Good luck, Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Hi Kate, you probably found the magnetic susceptibility which is often used for paramagnetic or diamagnetic materials: \chi = \mu_r - 1 Good luck, Edgar

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