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Definition of some parameters in Joule heating module

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Hi guys,
I am working on a simple geometry to simulate it with Joule heating module. While I am looking through equations in this module, I cann't find description of some of them. I appreciate if someone may help my about them:
1- Under Joule heating model for domains, what is Q_j (and its difference with Q) and J_e and also epsilon_0?
2- Under boundary electromagnetic heat source, what is Q_sh and since we have another boundary condition for electric field such as electric insulation, why we need boundary electromagnetic heat source?
I am sorry if the question looks awkward, but I really need to know what is going on within the fundamental equations of simulation.
Thanks a lot.

3 Replies Last Post 3 set 2014, 01:20 GMT-4

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Posted: 1 decade ago 29 ago 2014, 13:47 GMT-4
I am also curious about this question and hope it receives a reply.

I'm not specifically interested in the Joule heating module at the moment, but rather where to find better documentation of the equations used or conditions imposed by each node in the physics tree. The COMSOL documentation is often sparse. The advanced equation viewer within COMSOL provides more information, but is a headache to decipher without a reference of some sort for the variable names.
I am also curious about this question and hope it receives a reply. I'm not specifically interested in the Joule heating module at the moment, but rather where to find better documentation of the equations used or conditions imposed by each node in the physics tree. The COMSOL documentation is often sparse. The advanced equation viewer within COMSOL provides more information, but is a headache to decipher without a reference of some sort for the variable names.

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Posted: 1 decade ago 31 ago 2014, 01:24 GMT-4
Hi Mohsen,

1. Qj is a distributed current source, see the screenshot with a definition.
2. Je is an external current density, see the screenshot with a definition.
3. Maybe "epsilon_0" is actually "epsilon0_const" - permittivity of vacuum?
4. Compare the definitions of "boundary electromagnetic heat source" and "electric insulation" in the attached screenshots.

Best Regards,
Dima.

--
Dima Apter
www.a2z-consulting.com
Hi Mohsen, 1. Qj is a distributed current source, see the screenshot with a definition. 2. Je is an external current density, see the screenshot with a definition. 3. Maybe "epsilon_0" is actually "epsilon0_const" - permittivity of vacuum? 4. Compare the definitions of "boundary electromagnetic heat source" and "electric insulation" in the attached screenshots. Best Regards, Dima. -- Dima Apter www.a2z-consulting.com


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Posted: 1 decade ago 3 set 2014, 01:20 GMT-4
Thanks a lot Dima
Thanks a lot Dima

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