Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
Uncertain about damped (complex) frequency notation
Posted Mar 9, 2011, 11:17 a.m. EST Results & Visualization 4 Replies
Please login with a confirmed email address before reporting spam
Hi!
I could use help in fully understanding the notation of damped (complex) frequencies. From my understanding: The real part marks the damped frequency, and the imaginary part marks the damping.
Now, if the complex frequency is: omega=omega_d+i*damping, then the undamped frequency omega_0 is:
omega_0=sqrt(omega_d^2+2*damping^2)
Is this correct?
Thanks for the help!
I could use help in fully understanding the notation of damped (complex) frequencies. From my understanding: The real part marks the damped frequency, and the imaginary part marks the damping.
Now, if the complex frequency is: omega=omega_d+i*damping, then the undamped frequency omega_0 is:
omega_0=sqrt(omega_d^2+2*damping^2)
Is this correct?
Thanks for the help!
4 Replies Last Post Mar 10, 2011, 11:20 a.m. EST
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
almost, check it out with examples like this (see attached 4.1.0.185 file) now its there:)
or take a look at
en.wikipedia.org/wiki/Vibration#Damped_and_undamped_natural_frequencies
--
Good luck
Ivar
almost, check it out with examples like this (see attached 4.1.0.185 file) now its there:)
or take a look at
en.wikipedia.org/wiki/Vibration#Damped_and_undamped_natural_frequencies
--
Good luck
Ivar
Attachments:
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Thanks for the model!
So I what I am seeing is: f_d+zeta*f_n*i
The reason that I am uncertain: in acoustic eigenmode simulations this seems to not work out. Notation should be the same... What am I not getting?
So I what I am seeing is: f_d+zeta*f_n*i
The reason that I am uncertain: in acoustic eigenmode simulations this seems to not work out. Notation should be the same... What am I not getting?
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
HI
i do (unfortunately) not have the acoustic module so I have no experience with the specific physics used, could it be that there is a fluid damping feature that changes your constant (probably related to the viscosity, but I haven't opened my acoustic structure books for a few years ;)
--
Good luck
Ivar
i do (unfortunately) not have the acoustic module so I have no experience with the specific physics used, could it be that there is a fluid damping feature that changes your constant (probably related to the viscosity, but I haven't opened my acoustic structure books for a few years ;)
--
Good luck
Ivar
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Thanks!