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mef.d variable AC DC module

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I've been working with mef physics in the AC/DC module lately, and I noticed a variable mef.d that I couldn't find a definition for. It's used in the weak expressions for Ampere's Law and current conservation, e.g.,

mef.d*(mef.Jx*test(Vx)+mef.Jy*test(Vy)+mef.Jz*test(Vz))

and

mef.d*(-mef.Hx*mef.testcurlAx-mef.Hy*mef.testcurlAy-mef.Hz*mef.testcurlAz+mef.Jx*test(mef.Adepx)+mef.Jy*test(mef.Adepy)+mef.Jz*test(mef.Adepz))

(see the leading factor out front). The fact it's preceded by a node call mef. and followed by an asterisk suggests to me that it's not the differentiation operator d( ).

The meaning of mef.d may be obvious to someone more familiar with the weak form derivations for these PDE's, but it escapes me. Anyone know what this variable is?

2 Replies Last Post 10.01.2017, 10:46 GMT-5
Henrik Sönnerlind COMSOL Employee

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Posted: 8 years ago 10.01.2017, 02:54 GMT-5
Hi,

It is the out-of-plane thickness, defined in the Thickness section on the settings for Magnetic and Electric Fields.

A general method of finding a variable:

1. Press Ctrl-F, which brings up the search dialog.
2. Type in what you search for, here mef.d, and press Find.
3. In the Find Results tab, where the results of the search, you can double click an entry to get to the relevant node in the model tree (assuming that Equation View is on).

Regards,
Henrik
Hi, It is the out-of-plane thickness, defined in the Thickness section on the settings for Magnetic and Electric Fields. A general method of finding a variable: 1. Press Ctrl-F, which brings up the search dialog. 2. Type in what you search for, here mef.d, and press Find. 3. In the Find Results tab, where the results of the search, you can double click an entry to get to the relevant node in the model tree (assuming that Equation View is on). Regards, Henrik

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Posted: 8 years ago 10.01.2017, 10:46 GMT-5
Thank you for your answer! And the general method you describe is most useful.
Thank you for your answer! And the general method you describe is most useful.

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