Page 18 - Using ANSYS for Finite Element Analysis Dynamic, Probabilistic, Design and Heat Transfer Analysis
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Dynamic analysis • 5
being applied to the structure as these loads could be in or out
of phase. For harmonic analysis, all loads applied to a structure
must have the SAME FREQUENCY.
5. Set the frequency range
Select Solution > Load Step Opts > Time/Frequency
> Freq and Substps...
As shown in the following window, specify a frequency
range of 0–100 Hz, 100 substeps, and stepped b.c. By doing this
we will be subjecting the beam to loads at 1 Hz, 2 Hz, 3 Hz, .....
100 Hz. We will specify a stepped boundary condition (KBC) as
this will ensure that the same amplitude (100 N) will be applied
for each of the frequencies. The ramped option, on the other hand,
would ramp up the amplitude where at 1 Hz the amplitude would
be 1 N and at 100 Hz the amplitude would be 100 N.
You should now have the following in the ANSYS Graphics
window
