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What's Enorm

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Dear Pro.

Here I want to ask some very basic questions:

1. What's Enorm in comsol?

2. What's relationship between Enorm and Ex(or Ey Ez)

7 Replies Last Post 7 sept. 2012, 12:23 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 7 juin 2012, 05:58 UTC−4
Hi

check your equation views, there you find the definitions (mostly)

I assume its the norm of E hence the scalar sqrt(Ex^2+Ey^2+Ez^2) where (Ex,Ey,Ez) is your field vector

--
Good luck
Ivar
Hi check your equation views, there you find the definitions (mostly) I assume its the norm of E hence the scalar sqrt(Ex^2+Ey^2+Ez^2) where (Ex,Ey,Ez) is your field vector -- Good luck Ivar

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Posted: 1 decade ago 7 juin 2012, 06:25 UTC−4
Thank you for your replay.

Best regards
Thank you for your replay. Best regards

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Posted: 1 decade ago 7 juin 2012, 10:33 UTC−4
I asked support this question a couple months ago and this is what they said:

"The variable normE is defined by the expression
sqrt(realdot(Ex,Ex)+realdot(Ey,Ey)+realdot(Ez,Ez)), where the operator
realdot(a,b) treats complex numbers a and b as if they were real-valued
vectors of length 2 and returns their dot product (like a shorthand form of
real(a*conj(b)), except in respect to its partial derivatives). More
information on the realdot() operator can be found in the COMSOL
Multiphysics User's Guide on p. 119"

It is a bit more involved that the square root of the sum of squares.
I asked support this question a couple months ago and this is what they said: "The variable normE is defined by the expression sqrt(realdot(Ex,Ex)+realdot(Ey,Ey)+realdot(Ez,Ez)), where the operator realdot(a,b) treats complex numbers a and b as if they were real-valued vectors of length 2 and returns their dot product (like a shorthand form of real(a*conj(b)), except in respect to its partial derivatives). More information on the realdot() operator can be found in the COMSOL Multiphysics User's Guide on p. 119" It is a bit more involved that the square root of the sum of squares.

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

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Posted: 1 decade ago 8 juin 2012, 00:53 UTC−4
Hi

you are perfectly correct,
because of the possible COMPLEX representations of the E field phasor you need then to use the realdot() operator, this applies several places, not only for E. It all depends in which study you are , thanks for the reminder

--
Good luck
Ivar
Hi you are perfectly correct, because of the possible COMPLEX representations of the E field phasor you need then to use the realdot() operator, this applies several places, not only for E. It all depends in which study you are , thanks for the reminder -- Good luck Ivar

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Posted: 1 decade ago 5 sept. 2012, 09:51 UTC−4
Hi Ivar,

Can you tell me how to get the complex value E from the comsol. it really annoyed me. I used comsol-matlab (mentioned in the following), but the value what I get is real value (not complex data), it should be the complex data (include phase), right?

Looking ofrward to your reply! thanks very much!!


e.g., if I want to get the Ey value.
yy=postplot(fem,'tridata',{'Ey','cont','internal','unit','V/m'},'solnum',index,'outtype','postdataonly');
the value waht I get is only real data (no imaginary part).
Hi Ivar, Can you tell me how to get the complex value E from the comsol. it really annoyed me. I used comsol-matlab (mentioned in the following), but the value what I get is real value (not complex data), it should be the complex data (include phase), right? Looking ofrward to your reply! thanks very much!! e.g., if I want to get the Ey value. yy=postplot(fem,'tridata',{'Ey','cont','internal','unit','V/m'},'solnum',index,'outtype','postdataonly'); the value waht I get is only real data (no imaginary part).

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

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Posted: 1 decade ago 5 sept. 2012, 16:11 UTC−4
Hi

COMSOL has the complex values stored, but you can only extract a scalar hence when youneed t fetch it in two steps as a real(E)+i*imag(E), and dump it via 2 real values and recombine with the "i" in matlab or EXcel or whatever you use

--
Good luck
Ivar
Hi COMSOL has the complex values stored, but you can only extract a scalar hence when youneed t fetch it in two steps as a real(E)+i*imag(E), and dump it via 2 real values and recombine with the "i" in matlab or EXcel or whatever you use -- Good luck Ivar

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Posted: 1 decade ago 7 sept. 2012, 12:23 UTC−4
you can export complex fields using "Export" node
you can export complex fields using "Export" node

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