Abaqus: Frequency Response Function Plot 1

[Wibbs13]

I am attempting to generate an FRF in Abaqus to be able to compare to experimental data taken with an impact-hammer/accelerometer/FFT-analyzer.
I know I can use the "Natural Frequency Extraction" step to generate the eigenvalues/natural freq. and associated mode shapes. But that's not entirely what I am after....

Reading through the user's manuals it sounds like the Random Response Analysis might be my best bet to accomplish this, but so far I haven't had much luck. If anyone has experience trying to do the same I would appreciate knowing what analysis step you used and any additional tips or advice.



Much Thanks,

-Wibbs13

 

[PamCrash]

Since the hammer impact experiment is highly instationary you have to model this problem in the time domain (*ModalDynamic or *Dynamic in Standard or Explicit). Results should be passed through an FFT analyzer afterwards.

Random reponse is based on an ergodic, stationary excitation which contains harmonic components and which has a more or less constant variance over time. This is the opposite to an impact. RR cannot be used.

Maybe steady state dynamics (frequency sweep) might be an option if you want to stay in the frequency domain