Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.
Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
about current density in coil
Posted 16 set 2013, 09:23 GMT-4 Low-Frequency Electromagnetics Version 4.2a 1 Reply
Please login with a confirmed email address before reporting spam
excuse me
i have a problem about the current density in coil .
I am using the sample "indutiv heating.mph" now, and I changed the current in the coil to 3500A, and changed the coil 's cross surface to rectangle, the frequency is 40kHz. the coil is single turn coil, but in the result, i use surface integration to see the current in the coil, it showed the current is 7700A, but if I use multe turn coil do the calculation (and set the number of turns is 1), the result showed the current is 3500A. I used 2D-axisymmetric.
Can anyone tell me the reason of this different, and which one is right? thank you.
sorry for poor English.
i have a problem about the current density in coil .
I am using the sample "indutiv heating.mph" now, and I changed the current in the coil to 3500A, and changed the coil 's cross surface to rectangle, the frequency is 40kHz. the coil is single turn coil, but in the result, i use surface integration to see the current in the coil, it showed the current is 7700A, but if I use multe turn coil do the calculation (and set the number of turns is 1), the result showed the current is 3500A. I used 2D-axisymmetric.
Can anyone tell me the reason of this different, and which one is right? thank you.
sorry for poor English.
1 Reply Last Post 21 set 2013, 16:58 GMT-4
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi,
I assume that you have integrated "normed current". If you integrate in the "phi" direction the result should be right.
Why this? The single turn coil model includes the skin - and the proximity effect. Possibly the current fractional flows in opposite direction. Those "wrong way driving" currents have to be subtracted to get the right sum. If only the amount added, the value is too high.
You can easily test it, if you picture the current density in "phi" direction.
Regards Ueli
I assume that you have integrated "normed current". If you integrate in the "phi" direction the result should be right.
Why this? The single turn coil model includes the skin - and the proximity effect. Possibly the current fractional flows in opposite direction. Those "wrong way driving" currents have to be subtracted to get the right sum. If only the amount added, the value is too high.
You can easily test it, if you picture the current density in "phi" direction.
Regards Ueli