Anindya,

I know the exact frequency content is difficult to assess from observation alone. In order to get a better view of the frequency content the force time history is Discrete Fourier Analyzed. Compressor is running at 960 RPM (16 Hz). As shown below in Harmonic Components plot, 2nd and 4th harmonics must be considered in CAESAR II harmonic analysis that means 32Hz and 64hz, as worst cases. But individual harmonic runs must be performed for other harmonics as well, to be sure all possibilities have been taken into account.
So, shaking force that I've shown above is exactly applied to node 100 is 450N peak-to-peak.

If you are to perform CAESAR II harmonic analysis, what do you input in harmonic force form? is it 225N or 450N ?