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Comsol 3.5 - RF module - Eigenfrequency - Why do I have a factor ' - 2 * i * pi' ?
Posted 9 nov. 2010, 08:59 UTC−5 2 Replies
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Hello,
Using Comsol 3.5 RF module with Matlab, I already found that you need to put the frequency multiplied by ' - 2 * i * pi' in the solver line (and you need to divide by the same factor the solutions you get to have the real frequencies).
The problem is now I want to import the fem structure calculated with Matlab in Comsol, to have a better vision of the solutions. But the different solutions have frequencies multiplied by ' - 2 * i * pi', whereas the same structure calculated only with Comsol has the 'right' value of frequencies.
It seems using a script is the reason for this factor, but is there a way to access the real frequencies when importing a fem structure calculated with Matlab ? I tried 'naively' to change the values of the solutions before importing, but I get the "Access to an object's fields is only permitted within its methods" error. Anyone has an idea ?
Thank You.
Using Comsol 3.5 RF module with Matlab, I already found that you need to put the frequency multiplied by ' - 2 * i * pi' in the solver line (and you need to divide by the same factor the solutions you get to have the real frequencies).
The problem is now I want to import the fem structure calculated with Matlab in Comsol, to have a better vision of the solutions. But the different solutions have frequencies multiplied by ' - 2 * i * pi', whereas the same structure calculated only with Comsol has the 'right' value of frequencies.
It seems using a script is the reason for this factor, but is there a way to access the real frequencies when importing a fem structure calculated with Matlab ? I tried 'naively' to change the values of the solutions before importing, but I get the "Access to an object's fields is only permitted within its methods" error. Anyone has an idea ?
Thank You.
2 Replies Last Post 9 nov. 2010, 13:31 UTC−5
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Posted:
1 decade ago
Hi
are you sure you have selected eigenfrequency in frequency mode and not eigenvalue mode ?
--
Good luck
Ivar
are you sure you have selected eigenfrequency in frequency mode and not eigenvalue mode ?
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi,
Actually, it is the exactly the opposite I should do, I need to use eigenvalues to have the real frequency values and not eigenfrequencies (I just tested, it works). But I wouldn't have thought of it if you didn't mention it, so thank you :D.
Now why the real frequency are eigenvalues and not eigenfrequencies with a Matlab script, I have no idea. At least if you know it, it works very well.
Actually, it is the exactly the opposite I should do, I need to use eigenvalues to have the real frequency values and not eigenfrequencies (I just tested, it works). But I wouldn't have thought of it if you didn't mention it, so thank you :D.
Now why the real frequency are eigenvalues and not eigenfrequencies with a Matlab script, I have no idea. At least if you know it, it works very well.