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Simulation of electromagnetic generated by a very short pulse

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Hello all!
I want to simulate the reflection and transmission of the electromagnetic generated by a discharge, who generates a very short pulse. The pulse can be described in following equation,

I=I0*[exp(-a*t)-exp(-b*t)],
where a=1e9, b=1e10,

I0 is the amplitude of the pulse.

So from this equation, I can obtain a pulse having duration time of 1e-8 s.
I want to simulation the electromagnetic generated by this pulse, seeing the reflection and transmission condition in a metal tank (height: 250mm, diameter:300mm).

How can I do with RF module and transient analyzing, use the electric dipole? or edge current?
Could you give me some suggestions OR is there any simmilar examples?
Thank you very much!

3 Replies Last Post Jan 27, 2012, 5:31 a.m. EST
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Hello Peng Wang

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Posted: 1 decade ago Jan 27, 2012, 4:17 a.m. EST
I too would like to see the transient behaviour of an electric dipole. have you had any success?
I too would like to see the transient behaviour of an electric dipole. have you had any success?

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Posted: 1 decade ago Jan 27, 2012, 5:23 a.m. EST
No. It seems that the simulation will consume much RAM. I need a stronger computer.
Let's keep in touch about this topic. Thanks.
No. It seems that the simulation will consume much RAM. I need a stronger computer. Let's keep in touch about this topic. Thanks.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jan 27, 2012, 5:31 a.m. EST
Hi

first thing to check is ACDC or RF ?
you decaying pulse ahas a FWHM of about 1E-9[s] hence c_const*1E-9 = 300[mm] approx. and that is the size of your chamber, so you are just inbetween the "good" validity of both physics
I would start with RF (TEMW) still and a fine mesh, (else you have ACDC MF in the time domain but you do not solve for V then not sure you get all phenomena you want in the conducting materials

Use alumped port as source, then you might shape it later at will

And if you simulate the metal chamber wall as bulk, while looking for skin effects, do not forget to use a boundary layer to resolve the "skin" region

--
Good luck
Ivar
Hi first thing to check is ACDC or RF ? you decaying pulse ahas a FWHM of about 1E-9[s] hence c_const*1E-9 = 300[mm] approx. and that is the size of your chamber, so you are just inbetween the "good" validity of both physics I would start with RF (TEMW) still and a fine mesh, (else you have ACDC MF in the time domain but you do not solve for V then not sure you get all phenomena you want in the conducting materials Use alumped port as source, then you might shape it later at will And if you simulate the metal chamber wall as bulk, while looking for skin effects, do not forget to use a boundary layer to resolve the "skin" region -- Good luck Ivar

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