bozosprzoj
Aerospace
- May 24, 2013
- 12
Hello!
I am planning to work on a problem dealing with non-linear vibration. All the simulations I have done in the past had to do with mechanical problems like nonlinear static analysis, or linear dynamics, like modal analysis or harmonic analysis.
The point of nonlinear vibration is that when the usual Amplitude/frequency graph, like this one;
Leans on right or the left side (depending if we have nonlinear hardening or softening) like on this picture (hardening is presented);
This two graphs give an impression that there are two or even three amplitudes assigned to one frequency, which is a bit hard to picture. In reality we get in nonlinear vibration systems, so called amplitude jumps like on third picture.
System undergoes nonlinear vibration because of large displacement, act of dissipation forces like friction, material nonlinearities…etc. In my problem I would excite the cantilever beam with large amplitude and this would make for large displacement in the beam, which would make the system undergo nonlinear vibration.
To make long story short, I would need to perform harmonic analysis on nonlinear system, to capture something like the amplitude jump and I would be very grateful to any information on how to do it.
Regards!
I am planning to work on a problem dealing with non-linear vibration. All the simulations I have done in the past had to do with mechanical problems like nonlinear static analysis, or linear dynamics, like modal analysis or harmonic analysis.
The point of nonlinear vibration is that when the usual Amplitude/frequency graph, like this one;
Leans on right or the left side (depending if we have nonlinear hardening or softening) like on this picture (hardening is presented);
This two graphs give an impression that there are two or even three amplitudes assigned to one frequency, which is a bit hard to picture. In reality we get in nonlinear vibration systems, so called amplitude jumps like on third picture.
System undergoes nonlinear vibration because of large displacement, act of dissipation forces like friction, material nonlinearities…etc. In my problem I would excite the cantilever beam with large amplitude and this would make for large displacement in the beam, which would make the system undergo nonlinear vibration.
To make long story short, I would need to perform harmonic analysis on nonlinear system, to capture something like the amplitude jump and I would be very grateful to any information on how to do it.
Regards!
