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How apply a sinusoidal voltage?

Posted 1 avr. 2014, 09:49 UTC−4 Low-Frequency Electromagnetics Version 5.1 11 Replies

Hanna T
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I'm using joule heating, time dependent domain.
11 Replies Last Post 29 sept. 2016, 20:44 UTC−4
Hanna T
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Posted: 1 decade ago 2 avr. 2014, 01:03 UTC−4

I'm using joule heating, time dependent domain.


Anyone? I'm trying apply a AC source.
[QUOTE] I'm using joule heating, time dependent domain. [/QUOTE] Anyone? I'm trying apply a AC source.
Benjamin TAMPIGNY
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Posted: 1 decade ago 2 avr. 2014, 02:29 UTC−4
Hello Hanna,

I would say: create an analytic function under global definitions node. Name it, let's say "Usin."
Now when you want to refer to it, write "Usin(t[1/s])" and it should work.
Hello Hanna, I would say: create an analytic function under global definitions node. Name it, let's say "Usin." Now when you want to refer to it, write "Usin(t[1/s])" and it should work.
Hanna T
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Posted: 1 decade ago 3 avr. 2014, 09:47 UTC−4
Hi

Thank you so so much!! It works!!!
Hi Thank you so so much!! It works!!!
Hanna T
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Posted: 1 decade ago 7 avr. 2014, 09:26 UTC−4
Hi, I did what you suggested, but the results are very strange. Is there another way to apply a voltage?

Thank you!
Hi, I did what you suggested, but the results are very strange. Is there another way to apply a voltage? Thank you!
Hazlee Illias
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Posted: 1 decade ago 7 avr. 2014, 13:24 UTC−4
Rayudu Nithin,

you can directly the function that you need for example:
V0*sin(2*pi*100*t) , for frequency of 100Hz

Regards
Rayudu Nithin, you can directly the function that you need for example: V0*sin(2*pi*100*t) , for frequency of 100Hz Regards
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago 7 avr. 2014, 13:40 UTC−4
Hanna,

if you just need a harmonic excitation you should consider using a frequency domain or frequency transient study.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Hanna, if you just need a harmonic excitation you should consider using a frequency domain or frequency transient study. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Hanna T
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Posted: 1 decade ago 7 avr. 2014, 13:54 UTC−4
Hi everyone,

I'm using time dependent domain, Joule heating model. Please, where should I write the function? I presume there is a predefined function that solves this problem. Sorry if I'm wrong.

Again, thanks for your help.
Hi everyone, I'm using time dependent domain, Joule heating model. Please, where should I write the function? I presume there is a predefined function that solves this problem. Sorry if I'm wrong. Again, thanks for your help.
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago 7 avr. 2014, 14:10 UTC−4

Is there a specific reason to use time dependent?

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Is there a specific reason to use time dependent? -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Hanna T
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Posted: 1 decade ago 7 avr. 2014, 14:18 UTC−4
Yes, I have to apply a AC voltage for 15 minutes.
Yes, I have to apply a AC voltage for 15 minutes.
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago 7 avr. 2014, 14:29 UTC−4

You can handle this much more effectively in a frequency-transient study, because it is normally not required to resolve the AC-waveform explicitely in coupled thermal-electromagnetic problems.
Have a look into the inductive heating example in the model library.

If you want to insist in explicit time dependent modeling you can write the time dependent function directly into the respective field in your boundary condition. Take care then, to set the time dependent solver to strict time stepping and choose the time stepping in order to resolve the waveform properly.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
You can handle this much more effectively in a frequency-transient study, because it is normally not required to resolve the AC-waveform explicitely in coupled thermal-electromagnetic problems. Have a look into the inductive heating example in the model library. If you want to insist in explicit time dependent modeling you can write the time dependent function directly into the respective field in your boundary condition. Take care then, to set the time dependent solver to strict time stepping and choose the time stepping in order to resolve the waveform properly. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com
Ken Zhu
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Posted: 8 years ago 29 sept. 2016, 20:44 UTC−4

Hanna,

if you just need a harmonic excitation you should consider using a frequency domain or frequency transient study.

Cheers
Edgar

--
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com




Dear Edgar,

I am also confused that when I set the "Coil current" as a rectangle function (starting at 100 ms and ending at 400 ms, ), the induced current density norm rises ahead of the "Coil current" density norm.
Why does this happen? From my point of view, the induced current density norm should lag behind the "Coil current" density norm.

Could you help me solve this problem?

Sincerely,
Ken
[QUOTE] Hanna, if you just need a harmonic excitation you should consider using a frequency domain or frequency transient study. Cheers Edgar -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com [/QUOTE] Dear Edgar, I am also confused that when I set the "Coil current" as a rectangle function (starting at 100 ms and ending at 400 ms, ), the induced current density norm rises ahead of the "Coil current" density norm. Why does this happen? From my point of view, the induced current density norm should lag behind the "Coil current" density norm. Could you help me solve this problem? Sincerely, Ken

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